EPA-600/R-98-055
May 1998
FINAL
Evaluation and Performance Assessment of
Innovative Low-VQC Contact Adhesives in
Wood Laminating Operations
Prepared by:
Sonji L. Turner, Dean R. Cornstubble, and Coleen M. Northeim
Research Triangle Institute
3040 Comwallis Road
P. 0. Box 12194
Research Triangle Park, North Carolina 27709
EPA Cooperative Agreement No. CR-8241 52
EPA Project Officer: Chester A. Vogel
U.S. Environmental Protection Agency
National Risk Management Research Laboratory
Air Pollution Prevention and Control Division
Research Triangle Park, North Carolina 27711
Prepared for:
U.S. Environmental Protection Agency
Office of Research and Development
Washington, DC 20460
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FOREWORD
The U. S. Environmental Protection Agency is charged by Congress with pro-
tecting the Nation's land, air, and water resources. Under a mandate of national
environmental laws, the Agency strives to formulate and implement actions lead-
ing to a compatible balance between human activities and the ability of natural
systems to support and nurture life. To meet this mandate, EPA's research
program is providing data and technical support for solving environmental pro-
blems today and building a science knowledge base necessary to manage our eco-
logical resources wisely, understand how pollutants affect our health, and pre-
vent or reduce environmental risks in the future.
The National Risk Management Research Laboratory is the Agency's center for
investigation of technological and management approaches for reducing risks
from threats to human health and the environment. The focus of the Laboratory's
research program is on methods for the prevention and control of pollution to air,
land, water, and subsurface resources; protection of water quality in public water
systems; remediation of contaminated sites and groundwater; and prevention and
control of indoor air pollution. The goal of this research effort is to catalyze
development and implementation of innovative, cost- effective environmental
technologies; develop scientific and engineering information needed by EPA to
support regulatory and policy decisions; and provide technical support and infor-
mation transfer to ensure effective implementation of environmental regulations
and strategies.
This publication has been produced as part of the Laboratory's strategic long-
term research plan. It is published and made available by EPA's Office of Re-
search and Development to assist the user community and to link researchers
with their clients.
E. Timothy Oppelt, Director
National Risk Management Research Laboratory
EPA REVIEW NOTICE
This report has been peer and administratively reviewed by the U.S. Environmental
Protection Agency, and approved for publication. Mention of trade names or
commercial products does not constitute endorsement or recommendation for use.
This document is available to the public through the National Technical Information
Service, Springfield, Virginia 22161.
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Executive Summary
The purpose of this research project was to evaluate and assess the performance, economics, and
emission reduction potential upon application of low-volatile organic compound (VOC) waterborne contact
adhesive formulations specifically in a manual laminating operation for assembling store fixtures.
The primary objective of this project was to determine whether three waterborne contact adhesives
could achieve adhesion performance levels equivalent to, or exceeding that of, a currently used solvent-
borne contact adhesive while emitting lower VOCs and/or hazardous air pollutants (HAPs) upon
application. Two secondary objectives were to determine the relative cost of using each alternative contact
adhesive as compared to the currently used product (hereinafter called the "Control"), and to estimate the
emission reduction potential from the use of each alternative adhesive.
The evaluation facility hosting this research wants to meet a long-term VOC regulation required by
its state's Industrial Adhesives Reasonably Available Control Technology regulation. The regulation states
that, as of July 1, 1996, facilities using adhesives or adhesive primers in the production of wood furniture,
wood office partitions, or wood entry or passage doors must comply with a short-term VOC emissions
limit. This limitation states that the adhesive/adhesive primer must have a solids content greater than or
equal to 23 percent by weight, as applied. By May 1, 1999, however, facilities must meet a long-term
emissions limit by using an adhesive/adhesive primer that does not emit VOCs in excess of 540 g/L
(4.5 Ib/gal), excluding water.
Since the facility wants to comply with the long-term emissions limit of 540 g/L (4.5 Ib/gal) VOC
content, they must find an alternative adhesive that they can use in their operation that will meet not only
this limit but also several other criteria, including cost-effectiveness, nonflammability, and ability to
achieve performance requirements demanded by customers. Thus, in cooperation with EPA, this research
project assisted this small business in evaluating several alternative contact adhesives using the above
criteria.
Results from the evaluation show that the actual and theoretical VOC emissions resulting from the
use of the waterborne adhesives were significantly lower than the emissions resulting from the use of the
Control. Actual applied VOC emissions per side measured in this evaluation averaged about
30.3 g/m2 (2.8 g/ft2) for the waterborne products compared to 143 g/m2 (13 g/ft2) for the solvent-borne
Control.
Furthermore, the waterborne adhesives were applied at application rates higher than recommended
by the manufacturer's rates, and the Control was applied at a lower rate than recommended by the
manufacturer. If the adhesives were applied at the generic application rates recommended by the
manufacturers then, theoretically, the VOC emissions from the application of the waterborne products
would have averaged approximately 13 g/m2 (1.2 g/ft2) as compared to the Control at 207 g/m2 (19.2 g/ft2).
However, discussions with adhesive vendors indicated that wide variations in the amount of dry solids
applied would not have an appreciable effect on performance.
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Based on the quantity of adhesive used during the evaluation, all waterborne products ranged from
approximately 4 to 10 times more costly per m2 to use than the Control. Note that these costs were
calculated on the basis of the cost for the adhesives and did not include costs for labor, application
equipment, environmental compliance, etc. Again, if the adhesives were applied at the generic application
rates recommended by the manufacturers, then the cost of using the waterborne products would have
ranged from approximately $0.22/m2 to 0.55/m2 ($0.02/ft2 to 0.05/ft2) versus the Control at $0.31/m2
($0.03/ft2) based on adhesive cost only.
The operator who applied the adhesives in this evaluation was unfamiliar with the use of
waterborne adhesives and the use of high-volume, low-pressure (HVLP) spray technology. Although
attempts were made to follow the spray equipment manufacturers' recommendations, this research suggests
that the operator's familiarity with the waterborne adhesive products and application equipment can
substantially affect the cost and VOC emissions associated with the adoption of a new product.
This report was submitted in partial fulfillment of EPA Cooperative Agreement No. CR-824 152
by Research Triangle Institute under the sponsorship of the U.S. EPA. This report covers a period from
October 1995 to October 1997, and work was completed October 1997.
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Table of Contents
Executive Summary
Figures v
Tables • • v
Section 1.0 Project Description 1
1.1 Overview 1
1.2 Background 1
1.3 Store Fixtures Manufacturing 2
1.4 Evaluation Facility 3
1.4.1 Substrate and Laminate Cutting 3
1.4.2 Laminating 3
1.4.3 Facility Experience with Alternative Adhesives 5
Section 2.0 Materials and Methods 6
2.1 Materials 6
2.1.1 Adhesives 6
2.1.2 Boards 6
2.1.3 Laminates 6
2.2 Measurements 7
2.3 Evaluations 8
2.3.1 Onsite Subjective Peel Test 10
2.3.2 Offsite Cyclic Temperature-exposure Test 12
2.3.3 Offsite Peel Strength Evaluation 12
2.3.4 Offsite Determination of Each Adhesive's Physical Properties 12
Section 3.0 Results 14
3.1 On-Site Peel Observation 14
3.2 Peel Strength Test 14
3.3 Temperature Exposure Test 15
3.4 Adhesive Dry Times and Total Application Times 16
3.5 Adhesive Usage 17
3.6 Emission Estimates 18
3.6.1 Physical Properties 18
3.6.2 Emissions 19
3.7 Estimated Costs of Alternative Adhesives 20
3.8 Data Quality 20
Section 4.0 Conclusions 22
Section 5.0 Recommendations 24
Section 6.0 References 25
IV
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Table of Contents (cont.)
Page
Appendix A Conversion Factors A-l
Appendix B Test Preparation and Testing Procedures B- 1
Appendix C Descriptions of Test Methods C- 1
Appendix D TestData D-l
Appendix E Physical Property Data E-l
Appendix F Calculations for Table 3-7 F-l
Appendix G Calculations for Table 3-8 G-l
FIGURES
1-1 Operator spraying adhesive onto board 4
1-2 Operator laminating Formica to substrate using a 5-cm diameter roller 4
2-1 Picture illustrating the facility's conventional air spray gun 9
2-2 Picture illustrates the BINKS Mach 1 HVLP gun used in the evaluation 9
2-3 Weighing of pressure pot used in the evaluation 10
2-4 Example of how one manually checks for strands between laminate and substrate 11
2-5 A piece of pulled laminate from one of the Control samples illustrating what the plant
manager looks for in terms of number of strands 11
TABLES
2-1 Contact Adhesives Evaluated 1
2-2 Exposure Test Conditions 12
2-3 Physical Analysis of Adhesive Samples 13
3-1 Subjective Peel Test Results 14
3-2 Peel Strength Test Results 15
3-3 Observation Results of Temperature Exposure Tests 16
3-4 Average Application, Dry, and Total Application Times 16
3-5 Average Adhesive Used per Board/Laminate Assembly 17
3-6 Analytical Results for Each Adhesive 18
3-7 Applied VOC Emissions for Each Adhesive 19
3-8 Adhesive Coverage and Cost Information 21
4-1 Summary of Results 23
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Section 1.0
Project Description
1.1 Overview
The purpose of this research project was to evaluate and assess the performance, economics, and
emission reduction potential upon application of low-volatile organic compound (VOC) waterborne
contact adhesive formulations specifically in a manual laminating operation for assembling store fixtures.
The primary objective of this project was to determine if three waterborne contact adhesives
could achieve adhesion performance levels equivalent to, or exceeding that of, a currently used solvent-
borne contact adhesive while emitting lower VOCs and/or hazardous air pollutants (HAPs) upon
application. Two secondary objectives were to determine the relative cost of using each alternative
contact adhesive as compared to the currently used control, and to estimate the emission reduction
potential from the use of each alternative contact adhesive.
Research Triangle Institute (RTI) worked in cooperation with the U.S. Environmental Protection
Agency's (EPA's) Air Pollution Prevention and Control Division to coordinate this evaluation study with
(1) a store fixture manufacturing facility, (2) four contact adhesive suppliers, and (3) an independent
testing laboratory.
Results obtained from this study are intended to be used by facilities in the store fixture
laminating industry in their examination of low-VOC contact adhesives for their operations. Test results
from this evaluation will facilitate technology transfer of nonproprietary information to other businesses
facing similar emissions issues. The use of low-VOC contact adhesive formulations by manufacturers of
various laminated products to replace solvent-based contact adhesive formulations could ultimately
reduce the national VOC emissions from this industry.
1.2 Background
Over the past several years, manufacturers have been increasing the use of adhesives to replace
mechanical fasteners for industrial bonding. Manufacturers prefer adhesives for sensitive substrates such
as plastics where material stress must be distributed evenly to prevent failure. By the year 1998, U.S.
sales of adhesives and sealants are expected to reach $26.5 billion, with an average annual growth in
sales of 10.6 percent between 1988 and 1998.
In wood furniture manufacturing, manufacturers with lamination operations are realizing that the
most common cause of solvent emissions to the atmosphere are from the use of, specifically, contact
adhesives in these operations. In general, contact adhesives are defined as adhesives that are dry to the
touch in a relatively short period of time and that instantaneously adhere to themselves upon contact
(Mcllrath, 1993). These adhesives are used for laminating high-pressure laminate and low-pressure
laminates to various substrates. They are fast-bonding adhesives used to manufacture kitchen cabinets,
household and office furniture, and store fixtures.
Many contact adhesives are formulated with solvents that are classified as VOCs or HAPs, and
these solvents can represent more than 80 weight percent of the adhesive. Some solvents commonly used
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in formulating contact adhesives are hexane, methyl ethyl ketone, toluene, and methylene chloride, all of
which are VOCs and/or HAPs (Grumpier, 1996). Depending upon the application method employed,
cleanup activities generate hazardous waste materials that require special disposal.
From an emissions standpoint, in 1995, the national solvent utilization emissions of industrial
and non-industrial adhesives were 370,000 and 346,000 metric tons (407,000 and 380,000 short tons),
respectively.' These emissions combined represent 12.4 percent of the total emissions from solvent
utilization, which were 5,819,000 metric tons (6,394,000 short tons) in 1995.
To control emissions from the use of adhesives, manufacturers employ conventional end-of-the-
pipe control and treatment methods and systems, which can potentially be difficult to operate and
expensive to install. As an alternative approach, manufacturers have the option of converting to currently
available low- and no-VOC/HAP adhesive formulations. However, manufacturers are reluctant to make
this kind of change because of concerns related to the alternative materials meeting or exceeding cost and
performance requirements of their current products.
The focus of this project, then, was to evaluate low-emitting alternative adhesives that will aid in
the reduction of national VOC and HAP emissions from the use of contact adhesives in laminating
operations. Specifically, this project focuses on evaluating alternative waterborne contact adhesives in
the manufacture of retail store fixtures.
1.3 Store Fixtures Manufacturing
Manufacture of retail store fixtures involves forming and attaching several types of laminates to
particleboard or medium-density fiberboard substrates using contact adhesives. Examples of laminate
materials used to make store fixtures include melamine-impregnated papers, vinyl, top-coated papers, and
high-pressure laminates. Examples of retail store fixtures include refund counters, layaway department
counters, and sunglass stands. During assembly, both the laminate and substrate surfaces are coated with
a contact adhesive and allowed to dry, or cure, by air-drying, force-drying, or applying heat through an
external source. The laminate and substrate are then pressed together manually or mechanically using a
rotary press or nip roller to form a final bond (Choosing the Right Laminating Adhesives, 1988).
Many facilities that laminate wood products together with contact adhesives are looking for
alternatives to their current solvent-based contact adhesives in order to meet local, state, and Federal
regulations. These facilities are interested in alternatives that not only meet regulations but also perform
as well as, or better than, what they are currently using. Performance requirements include strength of
adhesion to both substrates, dry time, application time, low VOC content, and comparable costs to
currently used contact adhesives.
1 English units are prevalent in this industry. However, metric units are used throughout this report. For the reader's
convenience, a table is provided in Appendix A for converting Metric units to English units.
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1.4 Evaluation Facility
The evaluation facility hosting this research was a store fixtures manufacturer located in
Manitowoc, Wisconsin. This facility has been operating as a custom manufacturer of retail store fixtures
since October 1992. Their manufacturing space is approximately 2,044 m2 (22,000 ft2). The facility
operates 8 hours per day, 5 days per week, 260 days per year with a work force of 27 employees. With
respect to laminating activities, approximately 98 percent is performed in-house.
Before products can be laminated, the substrate and laminate must be cut to predetermined
dimensions. Substrate and laminate cutting and laminating operations are described below.
1.4.1 Substrate and Laminate Cutting
Substrate (herein referred to as board and/or substrate) is typically received at the facility in bulk
in what are called units. Each unit contains 35 sheets of boards each 1.22 m wide, 3.05 m long, and 0.02
m thick (4 ft by 10 ft by % in). These units are placed in temporary storage until they can be cut into
desired sections on a front loading beam saw. At the beam saw, operators manually feed three sheets of
boards at a time stacked on top of each other to the saw which cuts the boards to predetermined
dimensions. Since the machine is manually operated, only six units, or 210 sheets, can be cut per 8-h
shift.
The front loading beam saw is controlled by a computer which receives programming
instructions for cutting dimensions from a computer in the engineering department located in the main
office area of the facility. In addition, an operator manually enters additional information into the
computer pertaining to substrate type, cut size, etc., for printing identification labels for each set of cut
boards. The labels are then applied to the cut boards, indicating where the stack should be sent next for
processing.
Laminate is shipped to the facility in a similar fashion as the substrate. However, laminates are
supplied in many different shapes, colors, and varieties. They are made from Formica, melamine, vinyl,
or paper.
1.4.2 Laminating
Laminating activities primarily consist of Formica topping. Formica topping is performed
manually by two operators who apply adhesive and attach Formica laminates to particleboard or medium-
density fiberboard substrates. Figures 1-1 and 1-2 illustrate the laminating operation.
This process typically requires two operators. One operator cleans the surfaces of the board and
laminate and applies adhesive to one side of the board and to the opposing side of the laminate.
Adhesive application is performed by using a conventional air spray gun to apply a solvent-borne contact
adhesive. The adhesive is typically nearby and is supplied fed to the spray gun from a 208-L (55-gal)
drum. After adhesive is applied to the board and laminate, both substrates are set aside and the adhesive
is allowed to air-dry for approximately 30 min. Then, the second operator attaches the laminate to its
corresponding board by pressing the two surfaces firmly together. This operator uses a hand-held, 5-cm
(2-in)-diameter roller as a final press. The formed piece is typically allowed to air-dry for approximately
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Figure 1-1. Operator spraying adhesive onto board.
**•„ ''*
Figure 1-2. Operator laminating Formica to substrate using a 5-cm diameter roller.
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24 h before being sent to another station for assembly.
1.4.3 Facility Experience with Alternative Adhesives
The facility has experimented with several water-based contact adhesives over the past year and
a half, but none of these products dried quickly enough nor did they retain their adhesion to the substrate.
One product they evaluated in-house was a solvent-based adhesive having a VOC content of 610 g/L (5.1
Ib/gal). However, this facility wants to meet the long-term VOC regulation required by their state's
Industrial Adhesives Reasonably Available Control Technology (RACT) regulation. The regulation
states that, as of July 1, 1996, facilities using adhesives or adhesive primers in the production of wood
furniture, wood office partitions, or wood entry or passage doors must comply with a short-term VOC
emissions limit. This rule also states that the adhesive/adhesive primer must have a solids content greater
than or equal to 23 percent by weight, as applied. By May 1, 1999, however, facilities must meet a long-
term emissions limit by using an adhesive/adhesive primer that does not emit VOCs in excess of 540 g/L
(4.5 Ib/gal), excluding water.
Since the facility wants to comply with the long-term emissions limit of 540 g/L (4.5 Ib/gal)
VOC content, they have been looking for an alternative adhesive that they can use in their operation that
will meet not only this limit, but also meet several other criteria, including cost-effectiveness,
nonflammability, and the ability to achieve performance requirements demanded by their customers.
Thus, in cooperation with EPA, this research project assisted this small business in evaluating
several alternative contact adhesives using the above criteria.
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Section 2.0
Materials and Methods
This section describes the materials and methods used to evaluate the three alternative
waterborne contact adhesives as compared to the currently used solvent-borne adhesive, or Control. A
discussion of materials, measurements, and evaluations is included. Each is described below.
2.1 Materials
Three types of raw materials were used in this evaluation: adhesives, boards, and laminates.
2.1.1 Adhesives
The adhesives evaluated consisted of three waterborne contact adhesives and the Control.
Selection of the alternatives was based on the ability of each to meet the following criteria:
Contain less than 540 g/L (4.5 Ib/gal) of VOC;
Applicable to Formica topping or laminating;
Commercially available; and
Willingness of vendors to provide samples of, and technical information on, each adhesive.
Two of the three contact adhesives were single-component waterborne, and one was a two-component
waterborne. The Control was a single-component solvent-borne contact adhesive. A summary of each
adhesive is shown in Table 2- 1. A 19-L (5-gal) container of each adhesive was requested from each
vendor for the evaluation.
2.1.2 Boards
Boards most commonly used at this facility consist of industrial-grade particleboard and
medium-density fiberboard. The most common type of board is 20-kg (45-lb) density particleboard,
which makes up 95 percent of incoming stock. 20-kg (45-lb)-density particleboard was used as the
substrate in this evaluation. Four sheets of 3.05 m wide, 3.05 m long, and 1.91 cm thick (10 ft by 10 ft by
% in) were cut into 10, 1.22 m wide, 3.05 m long, and 1.91 cm thick sheets (4 ft by 10 ft by % in) to
provided a total of 40 boards for the evaluation. See Table B-2 in Appendix B to see how these 40 test
boards were distributed for the evaluation.
2.1.3 Laminates
The laminate evaluated consisted of Formica. Formica laminates were taken from a common lot,
pre-cut to dimensions slightly larger than the boards to which they were to be laminated.2
2 Laminate is always cut larger than the substrate to which it is applied so that an even edge can be achieved on all sides
after cutting away and sanding of excess laminate.
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Table 2-1. Contact Adhesives Evaluated
Adhesive 1
Adhesive 2
Adhesive 3
Control
Generic description
Resin base
Waterborne,
two-component
Polychloroprene
Waterborne,
single-component
Neoprene
Waterborne,
single-component
Rosin/terpene-
phenolic
Solvent-borne,
single-component
Polychloroprene
and phenol
Density, g/L
Solids, weight percent
Volatile types
Manufacturer's reported
volatile content, g/L d
Dry time, min
Part A " Part B c
1,126 - 1,066 -
1,174 1,114
47-51 15-19
Water Water,
toluene,
methanol
- 0
< 60
0.25-60
1,102
53.5
Toluene,
water
70-75
30
1,076
45
Toluene,
water
43
15 -30
755
17.5
Acetone,
n-hexane, hexane
isomers, and
toluene
623
15
1 Properties shown were taken from material safety data sheets and/or technical data sheets for each adhesive. Each
adhesive was supplied by a different adhesive manufacturer.
b Part A of Adhesive 1 is the activator for the adhesive of Adhesive 1. It is a zinc solution.
c Part B is the adhesive.
d Volatile content includes water and any exempt compounds.
1 lb/gal= 119.8 g/L.
2.2
Measurements
During application of each adhesive, the following measurements were taken:
• Initial and final weights of each board, laminate, and board/laminate assembly;
Initial and final weights of adhesive used during application to both boards and laminates;
Application time, including adhesive application and assembly;
Temperature and percent relative humidity during application and curing; and
Dry time of the assembled boards/laminates.
Weights of the boards, laminates, and the amount of adhesive used for each adhesive applied
were measured using a Sartorius 16000S floor scale, with a capacity of 16 kg (35 Ib) and a readability of
0.1 g (0.022 Ib). Application and dry times were recorded with a wrist watch to the nearest minute.
Temperature and percent relative humidity were measured at periodic intervals during each adhesive
application with a TSI VelociCalc, Model 8360 velocity meter rented from Response Rentals, Inc.
(temperature range -10 to 60°C [14 to 140°F] with a resolution of 0.1°C [0.2°F] and an accuracy of
±0.28°C [0.50°F]; relative humidity ranges from 20 to 95 percent with an accuracy of ±4 percent).
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No adjustments to these environmental conditions were made during the evaluation; however,
environmental conditions were monitored to determine if application conditions fell within each adhesive
vendor's recommendations. If conditions fell outside the recommended environmental conditions and
specifications, the dry times for each adhesive could have been negatively affected and could have taken
longer to dry than claimed by the vendors.
Contact adhesives used by the facility are spray applied using conventional air spray techniques.
Since the facility's long-term business goals are to convert to high-volume, low-pressure (HVLP) spray
technology, their current spray equipment, conventional air spray, was not used in this evaluation.
Instead, a local BINKS vendor supplied a new BINKS Mach 1 HVLP spray gun with appropriate fittings,
new 1 S-m long, 2-cm-diameter (5-ft, %-in) hoses, and a BINKS Model 80228 1.9-L (2-qt) pressure pot.
A separate hose was used for each adhesive to eliminate contamination between contact adhesives. The
spray gun and pressure pot were cleaned between adhesive applications with a cleaning solvent
recommended by each adhesive manufacturer and allowed to air-dry. Figures 2-1, 2-2, and 2-3 show the
facility's conventional air spray gun, and the HVLP spray gun and pressure pot used in the evaluation,
respectively.
For application of each adhesive, the facility selected an operator with 5 years of experience
spraying solvent-borne adhesives using conventional air spray technology. The operator had no
experience using HVLP spray technology. Thus, efforts were made to meet manufacturer
recommendations for the HVLP spray equipment settings and handling for each adhesive. To facilitate
this transition, the adhesive manufacturers furnished numerical values and other specific information on
each of their adhesives for each of the following variables:
• Complete procedures for adhesive set up and use instructions;
Parameters during adhesive application (e.g., rate of spread of film, number of coats applied,
environmental conditions); and
Recommended curing times and conditions.
2.3 Evaluations
Each adhesive evaluated was applied to several pairs of test boards and laminates. Then they
were laminated together and allowed to air-dry for approximately 24 h. Performance of each adhesive
was then evaluated on samples from the laminated assemblies using the following
observations/evaluations:
• Onsite subjective peel test;
Offsite cyclic temperature-exposure test;
Offsite peel strength evaluation; and
Offsite determination of each adhesive's physical properties.
Appendix B provides detailed descriptions of test preparations and measurement procedures used
to obtain gravimetric and environmental data at the facility.
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Figure 2-1. Picture illustrating the facility's conventional air spray gun.
Figure 2-2. Picture illustrates the BINKS Mach 1 HVLP gun used in the evaluation.
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Figure 2-3. Weighing of pressure pot used in the evaluation.
2.3.1 Onsite Subjective Peel Test
The subjective evaluation of test samples was conducted at the facility approximately 24 h after
adhesive application. This test is normally conducted at the facility as part of their routine quality
assurance check of assembled products. It consists of manually peeling back the laminate from the board
to observe how easily it can be pulled back and to count the number of strands remaining on the pulled
laminate. A strand is a piece of particleboard that is removed from the substrate and remains on the
laminate due to the adhesion strength of the adhesive. Figure 2-4 illustrates this concept. Figure 2-5 is a
piece of pulled laminate from one of the Control samples showing what the plant manager looks for in
terms of number of strands.
10
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Figure 2-4. Example of how one manually checks for strands between laminate and
substrate.
Figure 2-5. A piece of pulled laminate from one of the Control samples illustrating
what the plant manager looks for in terms of number of strands.
11
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2.3.2 Offsite Cyclic Temperature-exposure Test
Four sample boards from each adhesive set (A#S( 1-4)A and B) for temperature exposure testing
were packaged at the facility and shipped to RTI's Analytical and Chemical Sciences (ACS) research
laboratory, where they were immediately unwrapped and placed in stainless steel cans and sealed. These
cans contained both the control samples (A#S( 1-4)A) and exposure samples
(A#S( 1-4)B) in separate cans, respectively. The test samples were preconditioned for 7 days at 50 ±2
percent relative humidity and 23 ±1°C (73 ±1.8°F) before being placed in an incubator for cyclic,
temperature-exposure testing. The control samples remained in the control environment throughout the
test.
The preconditioned samples were subjected to two 24-h exposure cycles, cold then hot, at
conditions specified in Table 2-2.
Table 2-2. Exposure Test Conditions
Exposure cycle Temperature, °C Moisture conditions
Cold 0 Freezer, uncontrolled humidity
Hot 49 Open, uncontrolled humidity
1°F = 0.6°C.
2.3.3 Offsite Peel Strength Evaluation
The remaining test samples were packaged and shipped to SGS US Test Corporation, in
Fairfield, New Jersey, for peel strength evaluation of adhesive bonds using the American Society for
Testing of Materials (ASTM) Test Method D 903-93. An Instron Universal testing machine, Model
TTC, S/N 4384 was used with a 454 kg (1,000 Ib) load cell on a 9 kg (20 Ib) range, S/N 315 (load cell
accuracy is ±1 percent). See Appendix C for a summary of this test method.
2.3.4 Offsite Determination of Each Adhesive's Physical Properties
To determine each adhesive's physical properties, triplicate samples of each adhesive were
obtained. Before adhesive application, an operator thoroughly mixed each 19-L (5-gal) container of
adhesive. After opening each adhesives container, the operator took three grab samples from the center
of each container using 500-mL (17-fl-oz.) amber sample jars with sealing lids. These jars were supplied
by VWR Scientific. These samples were packaged and shipped to RTI's analytical laboratory and were
analyzed in triplicate for total volatiles, non-volatile content, water content, and density of each adhesive.
The analyses were conducted according to the standard test methods shown in Table 2-3. See Appendix
C for summaries of these test methods.
Physical property data were used to determine the secondary objectives of this evaluation,
determining VOC emissions as applied and relative costs of each adhesive as applied. These estimates
were calculated using each adhesive's percent solids by weight, and total weight loss of each adhesive
during application. Weight loss per adhesive was determined by recording the weight of the adhesive
12
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Table 2-3. Physical Analysis of Adhesive Samples
Physical Property Analysis Method Method description
VOC content EPA Method 24 Determination of volatile matter content, water content,
density, volume solids, and weight solids of surface
coatings
Nonvolatile content ASTMD 1489-93 Standard test method for nonvolatile content of aqueous
adhesives
Water content ASTM D 3792-79 Standard test method for water content of water-
reducible paints by direct injection into a gas
chromatograph
Density ASTM D 187.590 Standard test method for density of adhesives in fluid
form
in the pressure pot before and after each adhesive was applied to each board and laminate. The sum of
the adhesive usage for each board and laminate assembly was used in calculating VOC emissions.
See Appendix D for all weight test data, and VOC equations and examples. See Appendix E for
test results of physical property testing.
13
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Section 3.0
Results
This evaluation of three low-VOC waterborne contact adhesives and a solvent-borne Control
took place over a test period of 3 days at a store fixtures manufacturing facility in Manitowoc, Wisconsin
The ambient air temperature and percent relative humidity in the test area were monitored at periodic
intervals during adhesive application. The average temperature was 24°C (75 "F) and the average
percent relative humidity was 47 percent. These application conditions fell within the range of each
adhesive manufacturer's specifications.
This Section includes results from the on-site peel observation, off-site peel test, and the
temperature exposure test; adhesive dry times and total application times, and adhesive usage; and a
discussion of emission estimates, estimated costs of alternative adhesives, and data quality. Results from
each test are described below.
3.1 On-Site Peel Observation
The on-site peel observation was conducted by the plant manager on assemblies labeled A#S5O
through A#S9 approximately 18 to 22 h after adhesive application and lamination. To determine the
results of the peel test, each assembly was given a pass/fail rating by the plant manager. Table 3-1 shows
which adhesives passed and which failed for each set of tested assemblies.
Table 3-1. Subjective Peel Test Results
Assembly Number
A#S50
A#S6O
A#S7O
A#S8O
A#S9O
Adhesive 1
Pass
Pass
Pass
Pass
Pass
Adhesive 2
Pass
Pass
Pass
Pass
Pass
Adhesive 3
Fail
Fail
Fail
Fail
Fail
Control
Pass
Pass
Pass
Pass
Pass
The alternative waterborne adhesives, Adhesives 1 and 2, and the Control adhesive passed the
subjective peel test at the facility. Every laminate fully delaminated from each test assembly for
Adhesive 3. However, with longer cure times, this adhesive did achieve adequate peel strength (See
Section 3.2 discussion).
3.2 Peel Strength Test
Peel strength testing was conducted at SGS US Test Corporation in Fairfield, New Jersey. This
laboratory conducted a peel strength test using ASTM Method D 903-93 on each of the five test samples
from test board 10 of each adhesive set. Test method D 903-93 is designed for a flexible laminate that
14
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can be pulled back at a 180" angle. Because the Formica laminate used in this test was somewhat
inflexible, the testing laboratory had to modify this test. The testing facility found that the samples were
too stiff to be pulled back at a 90" angle as specified by the ASTM test method. Thus, the samples were
adjusted to a 22" angle to the horizontal to keep the laminates from cracking across their widths. The
rate at which the testing apparatus pulled each laminate back was 30 cm/min (12 in/min). Ambient
conditions were 23 °C (73°F) and 50 percent relative humidity. The results from the peel strength test
are shown in Table 3-2.
Table 3-2. Peel Strength Test Results
Adhesive 1 Adhesive 2
Average Peel Strength, kg/30 cm/min 6.4 a 3.6
Adhesive 3 Control
6.9 3.4 b
" The laminate for test sample 1 cracked before the true peel strength could be measured. The result was not included in the
average shown.
b The laminates for test samples 2, 3, and 4 cracked before the true peel strength could be measured. The results were not
included in the average shown.
1 Ib = 0.454 kg.
In comparison to the Control, all of the adhesives had equal or better peel strengths. Adhesives 1
and 3 had peel strengths of about twice the control, indicating a stronger bond than the Control adhesive.
As discussed above, Adhesive 3 had failed with the subjective peel strength tests conducted at the facility
after a 24-hour cure. In that test, each test sample for Adhesive 3 failed, delaminating completely from
each board. The reason for this difference could be attributed to the length of cure time of more than
four weeks between the sample leaving the facility and testing. It was beyond the scope of this study to
determine how long a cure period at ambient or higher temperatures would be required for Adhesive 3 to
reach adequate peel strength.
3.3 Temperature Exposure Test
At the end of the temperature exposure testing period (See Section 2.3.2), the exposed test
samples were allowed to reach room temperature. After reaching room temperature, the evaluation
facility's plant manager performed a subjective peel test on the exposed test samples and compared their
performance with the performance of their corresponding conditioned samples. Table 3-3 shows the
results of the plant manager's observations.
Overall, the plant manager determined that the Control matched normal peel tests conducted at
the facility. However, one control test board, ASS3B, delaminated completely after prying of the edges
indicating a weak adhesive bond between the board and laminate. For Adhesive 1, the plant manager did
not find a difference between the conditioned and test samples. The bond was determined to be
sufficient for a passing rating and comparable to the Control. All of Adhesive 2's conditioned and
exposed test samples fully delaminated and were determined to have no difference in manual peel
strength. Adhesive 3 was determined to have no difference in manual peel strength between the
conditioned and exposed samples, except that it had a weaker bond than Adhesive 1, but a stronger bond
than Adhesive 2.
15
-------
Table 3-3. Observation Results of Temperature Exposure Tests
Sample #
A1S(1-4)B
A2S(1-4)B
A3S(1-4)B
ASS( 1-4)B a
Adhesive
1
2
3
Control
Result
Pass
Fail
Pass
Pass
"ASSSBdelaminated.
3.4 Adhesive Dry Times and Total Application Times
The amount of time it takes for an applied adhesive to dry affects not only the performance of
any laminated assembly but also the amount of time it takes an operator to put together that assembly. In
evaluating the performance of the alternative waterborne contact adhesives, the actual, or measured, dry
time of each adhesive and the total application time, or process time, for adhesive application to each
assembly were measured. Table 3-4 illustrates the measured dry times and total application times and the
manufacturer's recommended dry times for each adhesive. See Appendix D for equations and sample
calculations for dry times.
Table 3-4. Average Application, Dry, and Total Application Times
Adhesive 1 Adhesive 2 Adhesive 3 Control
Application time, min a
Measured dry time, min
Recommended dry time, min b
Total application time, min c
1
5
0.083 to 0.25
6
2
28
15
31
1
47
30
48
2
24
15
26
a Application time is the time it takes to apply adhesive to both the board and laminate.
b Assumes acceptable temperature and percent relative humidity as recommended by each manufacturer's technical data sheet
during application.
c Total application time includes the time it takes to apply adhesive to both the board and laminate, drying time before
lamination, and the time it takes to laminate the board and laminate together.
In comparison to the Control, Adhesive 1 had the quickest measured dry time of 5 min, whereas
Adhesive 3 had the longest of 47 min The measured dry time for Adhesive 2 was within four min of the
dry time for the Control. Adhesive 3 did not meet the dry time of the Control, although the dry time for
Adhesive 2 was comparable to the Control. With respect to the manufacturer's recommended dry times,
all of the adhesives dried more slowly than specified by the manufacturer's recommendations, but the dry
time for Adhesive 1 was very fast (21% of the control's dry time).
16
-------
Total application time, as defined by the facility, is the amount of time it takes an operator to
apply adhesive to both boards, allow each board to dry, and laminate them together for further
processing. As shown in Table 3-4, the total application time for Adhesive 1 was approximately four
times quicker than the Control. Total application times for Adhesives 2 and 3 were greater than the
Control.
Thus, overall, Adhesive 1 had the highest peel strength and the quickest dry and application
times as compared to the other waterborne adhesives and the Control.
3.5 Adhesive Usage
Another objective of this evaluation was to determine the average amount of adhesive used per
board/laminate assembly per adhesive tested and to use this information to calculate VOC emissions as
applied per assembly and the relative costs of using each adhesive. Table 3-5 shows the average
adhesive used and the dry solids applied per assembly and a comparison of measured versus the
manufacturer's recommended applied solids per square meter of area per side coated. See Appendix D
for equations and sample calculations for adhesive usage.
Table 3-5. Average Adhesive Used per Board/Laminate Assembly
Adhesive 1
Adhesive 2
Adhesive
Control
Adhesive used, e
' 5
Dry solids applied, g
Dry solids applied, g/m2 per side
105
48
6.5
83
44
59
168
74
100
64
6
8
Manufacturer's recommended
dry solids applied, g/m2 per side
32 '
32 '
32
22
a Average value.
1 lb = 454 g.
1 g/ft2 = 10.765 g/m*.
In Table 3-5, the resulting dry grams of each adhesive applied was about two to three times the
manufacturer's recommended amount. The Control, however, was applied at almost a third of the
recommended amount. The reasons for these results are: 1) the unfamiliarity of the operator with the
HVLP gun used, with different pressure settings, tip sizes, etc., and 2) a slightly larger, or excess, surface
area of laminate sprayed than the board (1.22 m by 0.30 m [4 ft by 1 ft]). This excess surface area3 had
adhesive on it and was included in the final board/laminate assembly weights used to calculate the dry
solids applied.
More experimentation is needed to optimize processes for use of waterborne adhesives to reduce
cost, and to maintain adequate peel strength. For example, more experimentation is needed to determine
Excess surface areas were not measured for each laminate. However, the approximate overhang was in the range of
1 to 4 cm (0.5 to 1.5 in) per side per test assembly. Also, there was no consistency in excess surface area between
assemblies.
17
-------
if Adhesive 1 can maintain adequate peel strength with less adhesive applied. Similarly, more
experimentation with Adhesive 3 with less adhesive applied is needed to determine if its cure time could
be shortened with a concurrent development of adequate peel strength.
3.6 Emission Estimates
3.6.1 Physical Properties
A secondary objective of this evaluation was to compare estimates of VOC emissions of each
adhesive, as applied. To calculate estimates of applied VOC emissions from each adhesive, physical
properties including VOC content minus water, adhesive density, and weight percent solids were
determined. Water content, in weight percent, was determined to identify the amount of water in each
water based adhesive. Table 3-6 summarizes the analytical results for each adhesive's physical
properties.
Table 3-6. Analytical Results for Each Adhesive a
Adhesive I
Part Ab Part B c Adhesive 2 Adhesive 3 Control
VOC content d-e, g/L
Manufacturer's reported
VOC content, g/L 8
44'
0
145
<60
86
70-75
88
43
653
623
Density, g/L
Solids content, wt. %
Water content, wt. %
1,163
13.81
82.4 h
1,101
45.96
40.84
1,085
51.46
40.61
1,107
51.53
40.55
791
17.14
0.0038
a Values shown are the mean of three samples per adhesive.
b Part A is a zinc solution used to activate the adhesive, Part B.
c Part B is the adhesive.
d Adhesive VOC content is g of VOC per L of adhesive.
e No bias determined for VOC content measurements.
f By analysis method, zinc sulfate did not precipitate out completely prior to water analysis thus contributing to total volatiles.
g Manufacturer's reported VOC content is g of VOC per L of adhesive, including water and exempt solvents.
h Water content of Part A for Adhesive 1 analyzed by Karl Fischer titration method. Average shown is the mean of three
samples.
lib/gal =119.8 g/L.
As shown in Table 3-6, the analyzed VOC content of all of the alternative adhesives evaluated
met the facility's RACT limit on VOC content of 540 g/L (4.5 Ib/gal) for the year 1999. The differences
between the measured VOC contents and the manufacturer's VOC content can be explained by several
reasons. One, at relatively high temperatures, at testing conditions of 110°C (230 "F) in this case, it is
possible for some of the adhesive resin and other ingredients, such as unreacted resin monomers, to
evaporate. In addition, the samples may not have been well mixed. However, VOC content measured by
Method 24 includes solvents and any unreacted resin monomers that evaporate during the test. Also,
18
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historically, VOC contents of water based and exempt solvent materials measured by Method 24 have
been contested and differ from manufacturer claims because it is a directly measured value and not
calculated, as provided in most material safety data sheets.
3.6.2 Emissions
VOC emissions per unit of area for each adhesive were estimated using physical property data
from analytical testing, including VOC content and liquid density, the average quantity of wet adhesive
used per board/laminate assembly, and the surface area of the assembly. Table 3-7 shows the actual, or
measured, applied VOC emissions for each adhesive as compared to the theoretical VOC emissions as
applied based on the manufacturer's recommended application rates. See Appendix F for equations and
examples for calculating applied VOC emissions per unit area.
Table 3-7. Applied VOC Emissions for Each Adhesive "
VOC content, minus water, g/L
Density, g/L
Weight fraction solids, g/g
Wet adhesive usedg c
Wet adhesive used, L
Calculated VQC emissions g/m2 of assembly
based on weight of adhesivenisea
Theoretical covera^ g/m2 per side d
Theoretical VOC emissions g/m2, per assembly
Adhesive 1 b
145
1,101
0.4596
105
0.0954
37
32
19
Adhesive 2
86
1,085
0.5146
83
0.0765
18
32
10
Adhesive 3
88
1,107
0.5153
168
0.1518
36
32
10
Control
653
791
0.1714
64
0.0809
143
22
207
" Emissions are expressed as grams per square meter for a constant assembly area of 0.37 m2 (4 ft2).
b Assumes properties of Part B, the adhesive, of Adhesive 1 since the applied mix ratio of adhesive to activator is 15 parts of
adhesive, Part B, to 1 part of activator, Part A.
c Wet adhesive used is the average amount of adhesive used per board/laminate assembly and includes overspray.
d Theoretical coverage rates taken from each adhesive manufacturer's technical data sheets, which assumes 100 percent of the
adhesive applied solids ends up on the substrate.
lib/gal = 119.8 g/L.
1 Ib = 454 g.
1 gal = 3.7854 L.
Ig/ft2= 10.765 g/m2.
Table 3-7 shows that the average measured VOC emissions of the waterborne adhesives were
lower than the Control; this coincides with theoretical emission estimates based on manufacturer
recommendations. The VOC emissions are calculated from the solids content of each adhesive, VOC
content of each adhesive, and the quantity of adhesive applied to each assembly. Theoretical VOC
emission rates based on vendor recommendations for adhesive quantity per unit area were substantially
lower. Factors for deviations between measured and theoretical VOC emission estimates are adhesive
19
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overspray and the use of more adhesive on the substrate than recommended by adhesive manufacturers
(see Table 3-7). However, it is obvious from the data in Table 3-7 that, even when waterborne adhesives
are used in excess of their manufacturers specifications, over 90% reduction in VOC emissions can be
attained in comparison to the control adhesive.
3.7 Estimated Costs of Alternative Adhesives
Product density, weight percent solids, quantity applied (coverage), and cost data were used to
calculate cost estimates for each waterborne contact adhesive. The cost per L, the theoretical coverage
and cost, and the measured coverage and cost are shown in Table 3-8 for each adhesive. See Appendix G
for equations and examples for calculating adhesive coverage and cost information.
Based on the use rates of adhesive applied in this evaluation, the cost estimates in Table 3-8
show that the waterborne products are more costly to use than the Control for the same coverage area.
However, on a theoretical basis, only Adhesives 2 and 3 are less costly than the Control at approximately
three times the coverage area. The cost estimate for each alternative waterborne contact adhesive was
based solely on the cost of the adhesive and does not include equipment costs or the costs of
environmental compliance.
3.8 Data Quality
The primary objective of this project was to determine whether the application of low-VOC
contact adhesives can achieve performance levels equivalent to, or exceeding that of, solvent- based
contact adhesives while producing lower VOC and HAP emissions. To achieve this objective, weight
data were gathered on boards, laminates, and applied adhesive for each adhesive evaluated and used with
weight percent solids data on each adhesive.
Results from gravimetric measurements and ASTM test method measurements were within the
data quality objectives specified for this evaluation project, except for the application rates for applying
each adhesive. The rate at which each adhesive was applied in the test was higher than the
manufacturer's recommended application rate. The higher application rates caused the calculated VOC
emissions and estimated usage costs for each waterborne adhesive to be two to three times higher than
the theoretical values. However, this should not have effected adhesion performance of each adhesive
since discussions with adhesive vendors indicated that wide variations in the amount of dry solids
applied would not have an appreciable effect on adhesion performance between Formica laminates and
20-kg (45-Ib) density particleboard. In fact, the average range of adhesive applied per square meter per
side as quoted by the vendors was between 22 and 215 g/m2 (2 and 20 g/ft2). In addition, all of the
manufacturer's technical data sheets include standard disclaimers that, although an optimum rate of
adhesive applied is given to achieve optimum adhesion performance, the optimum rate is left to the user
to decide based on their own product quality requirements.
20
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Table 3-8. Adhesive Coverage and Cost Information
Density, g/L
Weight fraction solids, g/g
Dry solids applied, g b
Dry solids applied per side, g/m2
Theoretical dry solids applied, g/m2
COVERAGE
Theoretical coverage, m2/L
Measured coverage, m2/L
COSTS
Cost, US dollars/L on a 208-L basis c
Theoretical cost, US dollars/m*
Measured cost US. dollars/m*
Adhesive 1
1,101
0.4596
48
65
32
16
8
8.6
0.55
1.10
Adhesive 2
1,085
0.5146
44
59
32
17
9
3.9
0.22
0.41
Adhesive 3
1,107
0.5153
74
100
32
18
6
4.9
0.28
0.86
Control
791
0.1714
6
8
22
6.3
18
2.0
0.31
0.11
Cost estimates shown do not include costs for labor, equipment, or other costs like environmental compliance.
Control applied at 22 g/m2 dry adhesive solids per side. Theoretical coverage for the alternatives is calculated to be 32 g/m
drv adhesive solids aoolied oer side.
dry adhesive solids applied per side
c As of October 1996.
Ig/ft2=10.765g/m2.
1 ft2/gal = 0.025 m2/L.
1 gal = 3.7854 L.
1 ft2 = 0.093 m2.
21
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Section 4.0
Conclusions
This evaluation suggests that selected waterborne contact adhesives on an overall basis can
perform as well as or better than a solvent-borne contact adhesive that is currently being used in the store
fixture assembly industry. In fact, one of the better performing waterborne adhesives evaluated,
Adhesive 1, had actual dry times that were approximately five times lower than the Control. Although
this adhesive seemed to perform the best, it was the most expensive alternative tested. However, if more
rapid drying allows the throughput of product in these specific lamination activities to be increased, then
there could be cost savings from reduced inventory and increased production. Adhesive 2 had
comparable application and dry times to the Control, and passed the onsite peel strength test, but failed in
the temperature exposure test. Adhesive 3 appeared to have the lowest overall performance, failing in
the manual peel test at the facility and having total application and dry times of almost twice the Control.
The actual and theoretical VOC emissions resulting from the use of the waterborne adhesives
were significantly lower than the emissions resulting from the use of the Control. Actual applied VOC
emissions per side measured in this evaluation averaged about 30.3 g/m2 (2.8 g/ft2) for the waterborne
products and were 143 g/m2 (13 g/ft2) for the solvent-borne Control. If the adhesives were applied at the
generic application rates recommended by the manufacturers, then, on a theoretical basis, the theoretical
VOC emissions from the application of the waterborne products would have averaged approximately 13
g/m2 (1.2 g/ft2) as compared to the Control at 207 g/m2 (19.2 g/ft2).
The recommended application values were taken directly from the manufacturer's technical data
sheets for each adhesive. These values are generic and cover a range of laminating applications for
various industries, but they do not apply specifically to laminating applications for the store fixture
industry, nor specifically to this facility. Discussions with adhesive vendors indicated that wide
variations in the amount of dry solids applied would not have an appreciable effect on performance; for
example, for Adhesive 3, the vendor stated that no appreciable performance effects would be noticed up
to 161 g/m2 (15 g/ft2) of dry solids applied per side.
Based on the quantity of adhesive used during the evaluation, all waterborne products ranged
from approximately 4 to 10 times more costly per m2 to use than the Control. These costs were
calculated on the basis of the cost for the adhesives and did not include costs for labor, application
equipment, environmental compliance, etc. Again, if the adhesives were applied at the generic
application rates recommended by the manufacturers, then the cost of using the waterborne products
would have ranged from approximately $0.22/m2 to 0.55/m2 ($0.02/ft2 to 0.05/ft2) versus the Control at
$0.31/m2 ($0.03/ft2) based on adhesive cost only.
The quantity of applied dry solids had a direct impact on the cost and VOC emissions resulting
from the use of each adhesive. During the evaluation, due to the operator's lack of experience using
HVLP equipment, as shown in Table 3-5, the dry solids application rate for the waterborne adhesives
exceeded the manufacturers' recommended quantities while the application rate for the Control was
approximately three times less than recommended by the manufacturer. The VOC emissions and cost of
adhesive used would be substantially lower if the waterborne adhesives were applied as recommended by
the manufacturers.
22
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The reason why Adhesive 3 failed the subjective peel test and passed the temperature exposure
peel strength test is not certain. However, an extensive dry time between the adhesive samples leaving
the plant and the time at which they were tested at SGS US Test Corporation could explain why this
occurred. The adhesive could have continued to dry beyond the initial 24 h and could have become
stronger in bond strength. The results are summarized in Table 4.1 below.
The reader should note that the operator who applied the adhesive was unfamiliar with the use of
waterborne adhesives and the HVLP spray system used to apply the waterborne adhesives. Table 3-5
illustrates that, although the operator was quite familiar with the application of the Control adhesive,
their inexperience with HVLP spray technology made a difference (8 vs. 22 g/m2; 0.7 vs. 2.0 g/ft2) in
application rates. Although attempts were made to follow the spray equipment manufacturers'
recommendations, this research suggests that the operator's familiarity with the adhesive products and
application equipment can substantially affect the cost and VOC emissions associated with the adoption
of a new product. Appropriate operator training is essential to a successful switch to HVLP spray
technology.
In addition, the analyzed VOC content of each alternative adhesive evaluated ranged from 86 to
145 g/L (0.72 to 1.2 Ib/gal). These values met the facility's RACT limit on VOC content of 540 g/L (4.5
Ib/gal) for the year 1999.
Table 4.1. Summary of Results
Dry Time (min)
PeelStrength(lShr)
Peel Strength (kg/30
Control
24
Pass
3.4
Adhesive 1
5
Pass
6.4
Adhesive 2
28
Pass
3.6
Adhesive 3
47
Fail
6.9
cm/min)
Peel Strength After Pass Pass Fail Pass
Conditioning*
Cost of Adhesive (S/L) 2.0 8.6 3.9 4.9
* Samples conditioned 24 hours at 0° C and then 24 hours at 49°C both with uncontrolled
humidity
23
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Section 5.0
Recommendations
This evaluation was conducted as a proof-of-concept research project. The concept was to
evaluate adhesive performance of three alternative contact adhesives that contained less than 540 g/L
VOC (5.2 Ib/gal) and to evaluate their VOC emissions upon application versus a currently used solvent-
borne Control as each was applied to a representative surface area of substrate and laminate in a store
fixtures laminating facility. Each alternative adhesive and the Control was applied using HVLP spray
technology. As a result of the observations discussed in this evaluation, the following recommendations
are suggested for consideration as objectives for future research work in the adhesives industry.
Future testing of adhesive performance and VOC emissions, as applied, regardless of low-VOC
adhesive type, should be conducted further to investigate four critical factors in the wood laminating
industry:
• determine to monitor the effect of using alternative low-emitting adhesives on the throughput rate
of a lamination facility,
• to evaluate the effects of different spray technologies on these adhesives,
• to perform a total cost accounting of this evaluation, and
• to observe applications of alternative adhesives in other laminating operations where solvent-
borne contact adhesives still predominate.
24
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Section 6.0
References
Choosing the Right Laminating Adhesives. 1988. Furniture Design and Manufacturing (60): 160-
166, December.
Grumpier, P. 1996. Analysis of Pollution Prevention Opportunities and Impediments in the
Wood Products Manufacturing Sector in Georgia. Georgia Department of Natural
Resources, Atlanta, Georgia. April 1.
Mcllrath, D.H. 1993. A new approach to formulating waterborne contact adhesives. Adhesive
Age. 36( 12): 38-41.
25
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Appendix A
Conversion Factors
To Convert from Metic
LENGTH
meter
meter
centimeter
AREA
square meter
MASS OR WEIGHT
gram
kilogram
metric ton
VOLUME
liter
milliliter
DENSITY
grams per liter
TEMPERATURE
Celsius
Units
m
m
cm
m2
g
kg
m ton
L
mL
g/L
°C
To English
feet
inch
inch
square feet
pound
pound
short ton
gallon
fluid ounce
pounds per gallon
Fahrenheit
Units
ft
in
in
ft2
Ib
Ib
s ton
gal
fl.oz.
Ib/gal
oF
Multiply by
3.281
39.37
2.54
10.765
0.0022
2.205
0.907
0.264
0.034
119.8
multiply by 1.8, then add 32
A- I
-------
Appendix B
Test Preparation and Testing Procedures
B.I Test Preparation Procedures
Test preparation procedures for this evaluation consisted of adhesive application, adhesive
application to boards dedicated for off-site cyclic temperature exposure testing, adhesive application to
boards dedicated for onsite subjective peel test, and adhesive application to boards dedicated for off-site
peel testing. Each is described below.
B.I.I Adhesive Application
The Test Matrix in Table B- 1 identifies the experimental design for adhesive application to test
boards and laminates and identification of dedicated samples for conducting performance tests.
The adhesive used per board and laminate were recorded for the first nine test boards per
adhesive. Weights for test board 10 were not taken because the samples required for peel testing do not
allow for complete coverage of the board and laminate. Thus, the weights obtained would not be
consistent with the other nine boards per adhesive set. However, weights, temperatures, relative
humidities, etc., were monitored during adhesive application to ensure that the same procedure was used
for board 10 as that for boards 1 through 9.
Table B-l. Testing Matrix
Test board/laminate assembly samples
Performance test
Paired samples for
temperature
exposure test
On-site subjective
peel test
Sample
1
2
3
4
5
6
7
8
9
Adhesive 1
A1S1A"
A1S1B
A1S2A
A1S2B
A1S3A
A1S3B
A1S4A
A1S4B
AlS5Ob
A1S6O
A1S7O
A1S8O
A1S9O
Adhesive 2
A2S1A
A2S1B
A2S2A
A2S2B
A2S3A
A2S3B
A2S4A
A2S4B
A2S50
A2S6O
A2S7O
A2S8O
A2S9O
Adhesive 3
A3S1A
A3S1B
A3S2A
A3S2B
A3S3A
A3S3B
A3S4A
A3S4B
A3S5O
A3S6O
A3S7O
A3S80
A3S90
Control
ASS1A
ASS1B
ASS2A
ASS2B
ASS3A
ASS3B
ASS4A
ASS4B
ASS50
ASS60
ASS70
ASS80
ASS90
(continued)
B- I
-------
Table B-l. (Continued)
Performance test
Off-site peel test
Samvle Adhesive 1
10 A1S10P1C
A1S10P2
A1S10P3
A1S10P4
A1S10P5
Test board/laminate
Adhesive 2
A2S10P1
A2S10P2
A2S10P3
A2S10P4
A2S 1 OPS
assembly samples
Adhesive 3
A3S10P1
A3S10P2
A3S10P3
A3S10P4
A3S10P5
Control
ASS10P1
ASS 10P2
ASS10P3
ASS10P4
ASS 1 OPS
a Al S 1A (Adhesive #1_, Sample # _!_, A control sample for cyclic temperature exposure testing). Al S 1 B adhesive #1, Sample
# 1_, B_ exposed sample for cyclic temperature exposure testing).
b A1S5O (Adhesive #]_, Sample 5, A subjective operator evaluation).
c A1S10P# (Adhesive #1, Sample#10, Peel observation #1).
B.1.2 Adhesive Application to Boards Dedicated for Off-site Cyclic Temperature Exposure Testing
After allowing the board/laminate assembly to air-dry for approximately 24 h, two identical test
samples were cut from the first four test boards; Figure B-l illustrates that sample, A, the Control
sample, would be used for conditioning at ambient conditions and sample B, would be used for cyclic
temperature exposure testing.
1.22 m long
15 cm wide
23 cm long
A1S1A"
23 cm long
A1S1B"
30cm
wide
a Al S 1 A adhesive #1_, Sample # ]_, A control sample).
b Al S IB (Adhesive #J, Sample # i, B exposed sample).
Thickness = 1.9 1 cm (% in)
1 ft = 0.3048 m.
1 in = 2.54 cm.
Figure B-l. Dimensions and sample locations/designations for each board/laminate assembly
labeled A#S( 1-4).
Samples A and B were cut from the center of the board and were each 23 cm long by 15 cm wide
(9 in by 6 in). Then, cut samples, 1A through 4A and IB through 4B, of each assembly were placed
inside a 20 cm wide by 30 cm tall (8 in x 12 in) (volume = 0.01-m", 0.349-ft3) friction-sealed steel cans,
respectively. The cans were shipped by overnight delivery to RTI. Figure B-2 shows how each set of
samples were packaged.
B-2
-------
15 cm diameter can
co
o
E
o
o
CO
CO
•5
CO
o
-Q
O)
c
O
O
CO
CM
BOARD
l_
LLI
^^H
BOARD
|_
V)
HI
•^^
BOARD
|_
V)
LU
BOARD
L_
-------
American Society for Testing and Materials (ASTM) Standard Test Method D 903-93. Method D-903-
93 requires that no adhesive be applied between the laminate and board up to 15 cm (6 in) from the edge
of a 30-cm long (12 in) test sample. See Appendix C for a more detailed explanation of this test method.
A piece of masking tape was applied to both board and laminate surfaces up to 15 cm (6 in) from the
edge of test board 10 before applying adhesive to the board and laminate. Figure B-4 illustrates where
masking tape was applied, where the adhesive was applied, and how the samples were taken from test
board 10. Figures B-5 and B-6 illustrate both board and laminate setup.
After masking tape was applied to a board and its respective laminate, adhesive was applied to
both surfaces. An incision was made 10 cm (4 in) from the edge of the test board and the adhesive was
pulled away with the masking tape. Both surfaces were laminated together and allowed to air dry. After
curing for approximately 24 h, the assembly was taken to a saw and 10 cm (4 in) of the board was cut off.
Then the required individual samples were cut. Figure B-7 illustrates the resulting cut samples.
1.22 m long
30 cm long samples
This
This
to be
has
cutoff adhesive- A1S10P4
AISIOPI
A1S10P2
A1S10P3
A1S10PS
J 2.5 cm wide
CO
O
CD
|g
5
o
a Al S 1 DPI adhesive #1, Sample # 10, Peel test sample 1).
Thickness =1.9 cm (% in).
1 ft = 0.3048 m.
1 in = 2.54 cm.
Figure B-4. Dimensions and sample locations/designations for adhesive application to each board
number 10 for peel testing.
B-4
-------
Figure B-5. Picture illustrates how tape was wrapped onto each laminate.
Figure B-6. Picture illustrates how tape was wrapped onto each substrate.
B-5
-------
Figure B-7. Resulting cut samples sent to SGS US Test Corporation for mechanical peel
strength testing.
B-6
-------
B.2 Testing Procedures
The following testing procedures were used in the evaluation of three alternative low-VOC
contact adhesives as compared to a Control at a manufacturing facility in Manitowoc, Wisconsin. A
Sartorius precision floor scale was used to measure the amount of each adhesive used per test
board/laminate assembly per adhesive. A hand-held monitor was used to periodically measure ambient
air temperature and percent relative humidity during the test. Step 1 was performed prior to the start of
the test and at the conclusion of the test. Steps 2 and 6 were repeated for each adhesive. Steps 3 and 4
were repeated for each adhesive application.
B.2.1 Step 1 Calibration of Sartorius F16000S Floor Scale (The scale was turned on at the start of
each test day and turned off at the completion of each test day.)
1.1 Turn on the scale. Wait 30 minutes for equilibration.
1.2 Tare the scale to zero.
1.3 Place a 10-kg (22 Ib) calibration weight onto the center of the scale and record the weight.
1.4 If the net value of the weight added in Step 1.3 is 10 kg (22 Ib) ± 0.1 g (0.0035 oz),
continue. If not, perform an internal calibration (option included in scale model) and
repeat steps 1.2 to 1.4.
1.5 Remove the lO-kg (22 Ib) calibration weight.
1.6 Tare the scale to zero.
B.2.2 Step 2 Procedure for Preparing Each Test Piece Before Testing (A permanent marker was
used for labeling purposes.)
BOARDS
2.1 Remove a 1.22 m wide by 3.1 m long by 1.9 cm thick (4 ft x 10 ft x % in) particleboard
sheet from one common unit. One common unit consists of 35 particleboard sheets.
2.2 On the back of the sheet, measure and mark off ten, 1.22 m long by 30 cm wide (4 ft by 1
ft) sections.
2.3 Label each section as follows
On the back of sections # 1, 2, 3, and 4:
2.3.1 Label as A1S1 (Adhesive, #, Section, #).
2.3.2 Measure and mark off two, 15 cm wide by 23 cm long (6 in x 9 in) sections
equidistant from each side of the 1.22 m long by 30 cm wide (4 ft x 1 ft) section.
2.3.3 Label these two sections A1S1A and A1S1B. (A is the control sample and B is
the exposure sample for cyclic temperature exposure testing.)
On the back of sections # 5, 6, 7, 8, and 9:
2.3.4 Label as A1S5O (Adhesive, #, Section, #, Operator peel test).
On the back of section #10:
2.3.5 Label as A1S10P (Adhesive, #, Section, #, Peel test).
2.3.6 Measure and mark off five, 2.5 cm wide by 30 cm long (1 in x 12 in) sections
from a 30 cm (1 ft) wide side.
2.3.7 Label as A1S10P1 (Adhesive, #, Section, #, Peel test, #).
2.3.8 Measure and mark off 10 cm (4 in) and 15 cm (6 in) inward from the ed^;6 of the
board into 2.5 cm by 30 cm (1 in x 12 in) sections.
2.3.9 Apply masking tape over the entire 6-in area from the edge of the 30 cm (1 ft)
side into 2.5 cm by 30 cm (1 in x 12 in) sections.
B-7
-------
2.4 Cut the 1.22 m wide by 3.1 m long by 1.9 cm thick (4 ft x 10 ft x % in) sheet into its 10
equivalent 1.22 m long by 30 cm wide (4 ft x 1 ft) sections.
2.5 Clean the surface of the board by applying compressed air to its surface.
2.6 Place the 1.22 m long by 30 cm wide (4 ft x 1 ft) section on the floor scale. Record the
weight. This is the weight of each board for each 1.22 m long by 30 cm wide (4 ft x 1 ft)
section.
LAMINATES
2.7 Remove Formica laminate from one common lot to cover no less than 0.37 m2 (4 ft2).
2.8 On the back of each Formica laminate, label each to match the labeling for the board as
prescribed in Step 2.3.
2.9 Clean the surface of the laminate by applying compressed air to its surface.
2.10 Place each cut section on the floor scale. Record the weight. This is the weight of each
laminate paired with a corresponding board.
B.2.3 Step 3 Procedure for Applying Contact Adhesive to Test Board/Laminate Assemblies Labeled
A#S(l-9)
3.1 Clean the surface of each test board and laminate by applying compressed air to the
surfaces.
3.2 Connect one end of a 1.5-m long, 1.9-cm-diameter (5-ft, %-in) hose to the BINKS 1.9 L (2-
qt) pressure pot of and the other end to the HVLP spray gun. Connect the air supply hose
to the HVLP gun. Tie down the air supply and adhesive feed hoses.
3.3 Connect the manufacturer's suggested spray gun tip to the spray gun.
3.4 Place the empty 1.9 L (2-qt) pressure pot and assembly on the center of the floor scale.
3.5 After allowing the scale to equilibrate, tare the scale to zero (tare out the weight of the
pressure pot).
3.6 Place the test board and test laminate side-by-side on a table in the testing area.
3.7 Thoroughly mix a 19-L (5-gal) container of adhesive to be applied by using a stirring rod.
3.8 Open adhesive container and take three, 500-mL (17-fl-oz) samples from the middle of the
container.
3.9 Pour adhesive into the clean and empty 1.9-L (2-qt) pressure pot.
3.10 Start the HVLP spray system. Make sure the 1.9-L (2-qt) pressure pot and scale are not
touching anything.
3.11 Make necessary adjustments to spray gun fan width, air pressure, etc., while spray applying
adhesive to a piece of cardboard. Make sure flow rate of adhesive is per the
manufacturer's recommended flow rate.
3.12 Once adjustments have been made, then record the scale weight. This is the starting
weight for the adhesive to be applied to one test board and laminate.
3.13 Apply adhesive to a test board and laminate while recording ambient air temperature and
percent relative humidity.
3.14 At the completion of the operator's application of adhesive to both test board and laminate,
record the scale's displayed weight. This weight is the final weight for adhesive
application to a test board and laminate and the starting weight for adhesive to be applied
to the next test board and laminate.
3.15 Set aside both the test board and laminate and allow them to air dry per the adhesive
manufacturer's recommendation. Record this length of time.
3.16 After drying, apply the laminate to the test board and secure them together using the
B-8
-------
facility's standard procedure. Place the assembly in a secured area of the testing facility.
3.17 Record the elapsed time between Steps 3.10 and 3.16. This the total application time.
B.2.4 Step 4 Procedure for Applying Adhesive to Test Board/Laminate Assemblies Labeled
4.1 Repeat Steps 3.1 to 3. 15.
4.2 After applying adhesive, remove the masking tape from both the board and the laminate,
being careful not to remove adhesive from the other portion of the board or the laminate.
4.3 Repeat Steps 3. 16 and 3. 17.
B.2.5 Step 5 Testing Procedure Between Applying Adhesive Types
5.1 Clean the 2-qt pot and spray gun after an adhesive has been applied with the
manufacturer's recommended cleaning solvent by circulating the solvent through the
system for a minimum of 5 min
5.2 Disassemble the application system, discard solution material per adhesive manufacturer's
written specifications, and allow separate assembly parts to thoroughly dry.
5.3 Replace the adhesive feed hose to the HVLP spray gun with a new 1.5-m long, 1.9-cm-
diameter (5-ft, %-in) hose.
5.4 Change spray gun tip for next adhesive, if necessary.
5.5 Reposition the 1.9-L (2-qt) pressure pot on the floor scale.
5.6 Tare the scale to zero.
5.7 Repeat instructions given in Step 3 of the procedure.
B.2.6 Step 6 Procedure for Final Weight Measurement of Each Test Board/Laminate Assembly
6.1 Allow each test board/laminate assembly labeled A#S( 1-9) to air dry at the facility for a
minimum of 24 h.
6.2 Clean the surface of each test board/laminate assembly by applying compressed air to their
surfaces.
6.3 Place each 1.22 m long by 30 cm wide (4 ft x 1 ft) test board/laminate assembly on the
floor scale. Record the weight. This is the combined weight of board, laminate, and
adhesive solids applied for each assembly.
B-9
-------
Appendix C
Descriptions of Test Methods
1. Peel Strength Test ASTM D 903-93
ASTM D 903-93, Peel or Stripping Strength of Adhesive Bonds, is used to determine the
comparative peel or stripping characteristics of adhesive bonds when tested on standard-sized specimens
and under defined conditions of pretreatment, temperature, and testing machine speed. Peel or stripping
strength is expressed as the average load per unit width (kg/mm or Ib/in) of bond line required to separate
a flexible member from a rigid member or another flexible member in the adhered area at a separation
angle of 180" and at a separation rate of 152 mm (6 in)/min.
2.
Sampling and Analytical Procedures for Obtaining Physical Properties of Each Adhesive
Sampling procedures for this evaluation are limited to the physical property testing conducted on
each of the alterative contacts adhesives and the Control. The procedures for taking these samples from
each contact adhesive are discussed in Section 2, Methods and Materials.
Samples of liquid adhesives were analyzed according to four ASTM test methods:
ASTM D 2369-81,
ASTM D 1489-93,
ASTM D 3792-79, and
ASTM D 1875-90.
These ASTM Methods are described below in Table C- 1.
Table C-l. Summary Table of Standard Methods and Procedures
VOC
Non-volatiles
Water Content
Density
Method number ASTM D 2369-81
Method title
Method type
Reference
Standard Test Method
for Volatile Content of
Coatings
See ASTM Method
below
CFR 40, Pt. 60, App. A,
Meth. 24
ASTM D 1489-93
Standard Test
Method for
Nonvolatile Content
of Aqueous
Adhesives
Gravimetric
ASTM
ASTM D 3792-79
Standard Test Method for
Water Content of Water-
Reducible Paints by Direct
Injection into a Gas
Chromatograph
Gas Chromato-graphic
ASTM
ASTM D 1875-95
Standard Test Method
for Density of
Adhesives in Fluid
Form
Gravimetric
ASTM
a VOC content of liquid adhesives was calculated, as is done with coatings by EPA Method 24, as weight fraction total
volatiles (or 1 .000 minus non-volatiles) minus weight fraction water.
b Density was used to calculate volume fraction of VOC.
C-l
-------
a. ASTMD 2369-81
ASTM D 2369-8 1. Standard Test Method for Volatile Content of Coatings, involves evaporation of
volatiles from a weighed sample of material at 110°C (230°F) for 1 h. Weight fraction of volatiles is
calculated as the weight lost by the sample during heating divided by the weight of the original sample.
b. ASTMD 1489-93
ASTM D 1489-93. Standard Test Method for Nonvolatile Content of Aqueous Adhesives, involves
evaporation to constant weight of an aqueous solution of the adhesive at 105°C (221 "F). Percent non-
volatiles is calculated as 100 times the weight of the residue following heating divided by the weight of
the original sample.
c. ASTM D 3792-79
ASTM D 3792-79. Standard Test Method for Water Content of Water-Reducible Paints by Direct
Injection into a Gas Chromatograph, involves measurement of the water present in a material by gas
chromatography with thermal conductivity detection (GC-TCD). A known mass of sample is dissolved
in a solvent (dimethylformamide or DMF) and spiked with a known mass of an internal standard
(2-propanol). The solution is then shaken thoroughly, any solids present are allowed to settle out, and a
0.001-mL (3.4 x 10"5 fl. oz.) volume of the supernatant liquid is injected directly into a GC-TCD. The
TCD response for water relative to the response for the internal standard (determined during calibration)
is used to calculate the mass of water in the original sample. The weight fraction of water is calculated
as the weight of water in the original sample divided by the weight of the original sample.
A. ASTM D 1875-95
ASTM D 1875-95. Standard Test Method for Density of Adhesives in Fluid Form, involves use of a
weight-per-gallon cup of known volume and subsequent measurement of the mass of sample required to
exactly fill the cup at 25 °C (77 "F). Density is calculated as the mass of sample required to exactly fill
the cup divided by the volume of the cup.
c-2
-------
Appendix D
Test Data
TABLE D-l. RAW WEIGHT DATA FOR BOARDS AND LAMINATES
Assembly
identification
A
A
A
A
A
A
A
A
A
1
1
1
1
1
1
1
1
1
S
S
S
s
s
s
s
s
s
1
2
3
4
5
6
7
8
9
0
0
0
0
o
Average
A
A
A
A
A
A
A
A
A
2
2
2
2
2
2
2
2
2
s
s
s
s
s
s
s
s
s
1
2
3
4
5
6
7
8
9
Board
weight, g
5,207
5179.
5,227
5,167
5,193
.3
1
.0
.5
.1
5,212.9
5,116.0
5,126
5,125
.1
.8
5,172.8
5,154.3
5,172.2
0
0
0
0
0
Average
5,141
5,170
5,207
5,217
5,114
5,086
5,117
.1
.6
.7
.5
.0
.0
.5
5,153.4
Laminate
weight, g
423.5
402.
403.
406.
400.
401.
407.
403.
9
.5
,2
1
,5
,2
1
402.3
405
.6
401.9
406.4
404.
404
405
405
405
403
407,
1
.5
.3
.0
.5
.9
.8
404.9
Total
weight, g
5,630
.8
5,582.0
5,630
5,573
.5
.7
5,593.2
5,614.4
5,523
5,529
5,528.
.2
.2
1
5,578.3
5,556
5,578
5,545
5,575
.2
.6
.2
.1
5,613.0
5,622
5,519
.5
.5
5,489.9
5,525
.3
5,558.4
1 g = 0.0022 Ib.
Equation and Example:
Total weight, in g, for test assembly Al S 1
board weight, g + laminate weight, g
5,207.3 g + 423.5 g
5,630.8 g
(continued)
D- I
-------
TABLE D-l. (Continued)
Assembly
identification
A
A
A
A
A
A
A
A
A
3
3
3
3
3
3
3
3
3
S
S
S
S
S
S
S
S
S
1
2
3
4
5
6
7
8
9
0
0
0
0
0
Average
Board
weight, g
5,161.7
5,171.6
5,179.2
5,202.0
5,171.6
5,278.7
5,049.6
5,020.5
5,070.3
5,145.0
Laminate
weight, g
400
403
398
402
400
399
381
405
396
398
.5
.0
.3
.3
.7
.4
.2
.8
.8
.7
Total
weight, g
5,562.2
5,574.6
5,577.5
5,604.3
5,572.3
5,678.1
5,430.8
5,426.3
5,467.1
5,543.7
A
A
A
A
A
A
A
A
A
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
1
2
3
4
5
6
7
8
9
0
0
0
0
0
Average
1 g =
5,249.0
5,310.1
5,342.0
5,329.0
5,300.0
5,354.2
5,243.0
5,178.0
5,239.4
5,282.7
400
398
397
400
407
411
397
399
395
400
.6
.8
.7
.0
.5
.2
.3
.2
.6
.9
5,649.6
5,708.9
5,739.7
5,729.0
5,707.5
5,765.4
5,640.3
5,577.2
5,635.0
5,683.6
0.0022 lb.
Equation and Example:
Total weight, in g, for
test assembly A3S 1
= board weight, g + laminate weight, g
= 5,161.7 g +400.5 g
= 5,562.2 g
D-2
-------
TABLE D-2. RAW WEIGHT DATA FOR THE ADHESIVES
Pot wt. before adhesive
Assembly application to board and laminate,
identification g
A
A
A
A
A
A
A
A
A
1
1
1
1
1
1
1
1
1
S
S
S
S
S
S
S
S
S
1
2
3
4
5
6
7
8
9
0
o
o
0
o
Average
A
A
A
A
A
A
A
A
A
2
2
2
2
2
2
2
2
2
S
S
S
S
S
S
S
S
S
1
2
3
4
5
6
7
8
9
0
0
o
o
o
Average
Eauation and
Example:
6,169.0
6,070.0
5,967.0
5,865.0
5,757.0
5,665.0
5,560.0
5,464.0
5.358.0
5,763.9
10,442.0
10,331.0
10,233.0
10,140.0
10,051.0
9,972.0
9,849.0
9,779.0
9.657.0
10,050.4
Pot wt. after adhesive application Adhesive
to board and laminate, g used, g
6,070.0
5,967.0
5,865.0
5,757.0
5,665.0
5,560.0
5,464.0
5,358.0
5.227.0
5,659.2
10,340.0
10,268.0
10,147.0
10,058.0
9,976.0
9,887.0
9,786.0
9,681.0
9.564.0
9,967.4
99.
103
102
108
92.
105
96.
106
131
104
102
63.
86.
82.
75.
85.
63.
98.
93.
83.
0
.0
.0
.0
0
.0
0
.0
.0
.7
.0
0
0
0
0
0
0
0
0
0
Adhesive used for test assembly Al S 1, in g
pot weight before adhesive application to board
and laminate, g +pot weight after adhesive
application to board and laminate, g
6,169.0 g +6,070.0 g
99.0 g
(continued)
D-3
-------
TABLE D-2. (Continued).
Pot weight before
Assembly adhesive application to
identification board and laminate, g
A
A
A
A
A
A
A
A
A
3
3
3
3
3
3
3
3
3
S
S
S
S
S
S
S
S
S
1
2
3
4
5
6
7
8
9
0
O
0
0
0
Average
A
A
A
A
A
A
A
A
A
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
1
2
3
4
5
6
7
8
9
0
0
0
0
0
Average
13,691.0
13,492.0
13,304.0
13,127.0
12,908.0
12,718.0
12591.0
12,459.0
12,320.0
12,956.7
11,431.6
11,378.0
11,310.0
11,234.0
11,165.0
11,094.0
11,026.0
10,940.0
10,875.0
11,161.5
Pot weight after
adhesive application to
board and laminate, g
13,492.0
13,304.0
13,127.0
12,908.0
12,718.0
12,591.0
12,459.0
12,320.0
12,180.0
12,788.8
11,387.6
11,313.0
11,249.0
11,179.0
11,090.0
11,029.0
10,947.0
10,889.0
10,790.0
11,097.1
Adhesive
used, g
199.0
188.0
177.0
219.0
190.0
127.0
132.0
139.0
140.0
167.9
44.0
65.0
61.0
55.0
75.0
65.0
79.0
51.0
85.0
64.4
1 g = 0.0022 Ib.
Eauation and
Example:
Adhesive used for test assembly ASS 1, in g
pot weight before adhesive application to board
and laminate, g +pot weight after adhesive
application to board and laminate, g
13,691.0 g+13,492.0 g
199.0 g
D-4
-------
TABLE D-3. APPLICATION AND DRY TIMES
Assembly
identification
A
A
A
A
A
A
A
A
A
1
1
1
1
1
1
1
1
1
S
S
S
S
S
S
S
S
S
1
2
3
4
5
6
7
8
9
Adhesive
application start
time
0
0
O
0
O
1515
1519
1522
1545
1546
1548
1551
1554
1556
Adhesive
application end
time
1516
1520
1523
1546
1547
1548
1551
1554
1556
Average
A
A
A
A
A
A
A
A
A
2
2
2
2
2
2
2
2
2
S
S
S
S
S
S
S
S
S
1
2
3
4
5
6
7
8
9
O
O
O
0
0
1234
1239
1243
1251
1254
1300
1309
1312
1315
1237
1241
1250
1253
1257
1302
1311
1314
1317
Average
Total
application
time, min "
1
1
1
1
1
1
1
1
1
1
3
2
7
2
3
2
2
2
2
3
Time laminated
1521
1525
1527
1550
1552
1555
1557
1558
1600
1303
1307
1317
1319
1324
1328
1339
1347
1349
Dry time,
min
5
5
4
4
5
7
6
4
4
5
26
26
27
26
27
26
28
33
32
28
Total application times were rounded up to the nearest minute. For example, since it took less than one minute total to apply
adhesive to both board and laminate for assembly Al S6O, the total application time was rounded up to one minute.
Equations and Examples:
Total application time for assembling A 1 S 1, min
Dry time for A1S1, min
= Adhesive application end time - adhesive application
start time
= 1516 - 1515
= Imin
Time laminated - adhesive application end time
= 1521 - 1516
5 min
(continued)
D-5
-------
TABLE D-3. (Continued)
Adhesive
Assembly application start
identification time
A
A
A
A
A
A
A
A
A
3
3
3
3
3
3
3
3
3
S
S
S
S
S
S
S
S
S
1
2
3
4
5
6
7
8
9
O
O
O
O
O
1437
1441
1443
1445
1446
1448
1450
1451
1452
Adhesive
application end
time
1438
1442
1444
1446
1447
1449
1450
1452
1453
Average
A
A
A
A
A
A
A
A
A
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
1
2
3
4
5
6
7
8
9
0
0
0
0
0
1354
1358
1401
1404
1408
1411
1419
1423
1430
1356
1400
1403
1406
1410
1413
1421
1425
1433
Average
Total
application
time, min "
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
3
2
Time laminated
1525
1529
1531
1536
1538
1540
1532
1535
1534
1413
1418
1425
1427
1439
1441
1443
1453
1500
Dry time,
min
47
47
47
50
51
51
42
43
41
47
17
18
22
21
29
28
22
28
27
24
"Total application times were rounded up to the nearest minute. For example, since it took less than one minute total to apply
adhesive to both board and laminate for assembly A3S7O, the total application time was rounded up to one minute.
Equations and Examples:
Total application time for assembling ASS 1, min
Dry time for A1S1, min
Adhesive application end time - adhesive application
start time
1437 . 1438
Imin
Time laminated - adhesive application end time
1525 - 1438
47min
D-6
-------
TABLE D-4. APPLIED SOLIDS TO ASSEMBLIES A#S(l-9)
Assembly
identification
A
A
A
A
A
A
A
A
A
1
1
1
1
1
1
1
1
1
S
S
S
S
S
S
S
S
S
1
2
3
4
5
6
7
8
9
Board and
laminate weight, g a
0
O
O
O
O
Average
A
A
A
A
A
A
A
A
A
2
2
2
2
2
2
2
2
2
S
S
S
S
S
S
S
S
S
1
2
3
4
5
6
7
8
9
O
O
O
0
O
Average
5,630.8
5,582.0
5,630.5
5,573.7
5,593.2
5,614.4
5,523.2
5,529.2
5,528.1
5,578.3
5,556.2
5,578.6
5,545.2
5,575.1
5,613.0
5,622.5
5,519.5
5,489.9
5,525.3
5,558.4
Weight of
board, laminate,
and adhesive, g
5,670.3
5,627.6
5,678.8
5,623.4
5,637.0
5,662.2
5,569.9
5,577.2
5,593.2
5,626.6
5,595.5
5,616.2
5,595.2
5,616.1
5,652.4
5,660.1
5,565.0
5,541.5
5,579.3
5,602.4
Applied
solids, g
39.
45.
48.
49.
43.
47.
46.
48.
65.
48.
39.
37.
50
41.
39
37,
45.
51.
54
44
5
6
3
7
8
8
7
0
1
3
3
,6
.0
,0
.4
.6
5
.6
.0
.0
"Weights taken from Table D-1.
g = 0.0022 Ib.
Eauations and Examples:
Applied solids for assembly Al S 1, in g
weight of board, laminate, and adhesive, g - board
and laminate wt, g
5,670.3 g - 5,630.8 g
39.5 g
(continued)
D-7
-------
TABLE D-4. (Continued)
Assembly Board and
identification laminate weight, g a
A
A
A
A
A
A
A
A
A
3
3
3
3
3
3
3
3
3
S
S
S
S
S
S
S
S
S
1
2
3
4
5 0
6 0
7 0
8 O
9 0
Average
A
A
A
A
A
A
A
A
A
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
1
2
3
4
5 0
6 0
7 0
8 0
9 0
Average
5,562.2
5,574.6
5,577.5
5,604.3
5,572.3
5,678.1
5,430.8
5,426.3
5,467.1
5,543.7
5,649.6
5,708.9
5,739.7
5,729.0
5,707.5
5,765.4
5,640.3
5,577.2
5.635.0
5,683.6
Weight of
board, laminate,
and adhesive, g
5,641.1
5,655.3
5,667.0
5,700.3
5,660.7
5,735.2
5,484.0
5,484.6
5,533.7
5,618.0
5,654.2
5,714.4
5,745.1
5,734.2
5,714
5,770
.7
.3
5,644.7
5,582
5.643.
.5
1
5,689.2
Applied
solids, g
78
80
89
96
88
57
53
58
66
74
4.
5.
5.
5.
7.
4.
.9
.7
.5
.0
.4
.1
.2
.3
.6
.3
6
5
4
2
2
9
4.4
5.
8.
5.
3
1
6
a Weights taken from Table D-l.
1 g = 0.0022 Ib.
Equations and Examples:
Applied solids for assembly ASS 1, in g
weight of board, laminate, and adhesive, g - board
and laminate wt, g
5,641.1 g-5,562.2 g
78.9 g
D-8
-------
Appendix E
Physical Property Data
DENSITY, WATER CONTENT, NON-VOLATILE MATTER CONTENT, AND
VOC CONTENT
Adhesive 1
Physical Property
Density, g/L c
Water content, g/g d
Non-volatile matter
content, g/g '
Method 24 VOC content,
g/g
Part A a
1,163
0.8240°
0.1381
0.0379
PartB"
1,101
0.4084
0.4596
0.1320
Adhesive 2
1,085
0.406 1
0.5 146
0.0793
Adhesive 3
1,107
0.4055
0.5153
0.0792
Control
791
0.0038
0.1714
0.8248
VOC content,gVOC/ L
of adhesive
VOC contentg VOC/L
of adhesive minus water
44
1134
145
265
86
154
88
160
653
655
Adhesive 1 Part A is the activator. It is a zinc solution.
Adhesive 1 Part B is the adhesive.
Values are measured values and are averages of three results from three samples (or six results averaged) of each adhesive,
except for Adhesive 1. Densities were measured according to ASTM D 1875-90 at 25°C (77°F).
Values are measured values and are averages of two results from two samples (or four results averaged) of each adhesive,
except for Adhesive 1. Water contents are shown in weight fractions and were measured according to ASTM D 3792.
Values are measured values and are averages of one result from three samples (or three results averaged). Water contents
are shown in weight fractions and were measured according to the Karl Fischer Titration method.
Values are measured values and are averages of four results from four samples (or eight results averaged) of each adhesive.
Non-volatile matter contents are shown in weight fractions and were measured according to ASTM D 2369
Equations and Examples for Adhesive 3:
Method 24 VOC content,
g of VOC / g of adhesive
VOC content,
g of VOC/L of adhesive
VOC content,
g of VOC/L of adhesive,
minus water
= 1 - (non-volatile matter content, g/g) - (water content, g/g)
= 1-0.5153-0.4055
= 0.0792
= (density, g/L) * (Method 24 VOC content)
= 0.7914 * 0.8248
= 652.75
[(VOC content, g of VOC/L of adhesive) / (1 - (density, g/L * water
content, g/g) / (density of water at 25 °C, g/L)]
= (1 * 88)/[I-(1,107*0.4055)/997.07)]
= 160 g/L
E-
-------
Appendix F
Calculations for Table 3-7
APPLIED VOC EMISSIONS FOR EACH ADHESIVE
VOC content, minus water, g/L
Density, g/L
Weight fraction solids, g/g
Wet adhesive usedg c
Wet adhesive used, L
Calculated VOC emissions g/m2, of assembly
based on weight of adhesive used
Theoretical coverage rate, g/m per side
Theoretical VOC emissions g/m2, per assembly
Adhesive 1 h
145
1,101
.4596
105
0.0954
37
32
19
Adhesive 2
86
1,085
.5146
83
0.0765
18
32
10
Adhesive 3
88
1,107
.5153
168
0.1518
36
32
10
Control
653
791
.1714
64
0.0809
143
22
207
a Emissions are expressed as grams per square meter for a constant assembly area of 0.37 m2 (4 ft2).
h Assumes properties of Part B, the adhesive, of Adhesive 1 since the applied mix ratio of adhesive to activator is 1 part of
adhesive, Part B, to 15 parts of the activator, Part A.
c Wet adhesive used is the average amount of adhesive used per board/laminate assembly and includes overspray.
d Theoretical coverage rates taken from each adhesive manufacturer's technical data sheets which assumes 100 percent of the
adhesive applied solids ends up on the substrate.
1 lb/gal= 119.8 g/L.
1 Ib = 454 g.
1 gal = 3.7854 L.
Ig/ft2=10.765g/m2.
Equations and Examples for Adhesive 3:
Wet adhesive used, L = (wet adhesive used, g) / (density, g/L)
= 168 g / 1,107 g/L
= 0.1518L
Calculated VOC emissions, = [(VOC content, g/L) * (wet adhesive used, L)] /
g/m', of assembly based on weight (assembly surface area adhesive applied to, m2)
of adhesive used
= (88 g/L * 0.1518 L) IO.37 m2
= 36 g/m2
Theoretical VOC emissions, = [(VOC content, g/L) * (theoretical coverage rate, g/m2, per side) * 2 sides] /
g/m2, per side [(weight fraction solids, g/g) * (density, g/L)]
= (88 g/L * 32 g/m2 * 2 sides) / (0.5153 * 1,107 g/L)
= 10 g/m2
F - I
-------
Appendix G
Calculations for Table 3-8
ADHESIVE COVERAGE AND COST INFORMATION
Density, g/L
Weight fraction solids, g/g
Dry solids applied, g a
Dry solids applied per side, g/m2
Theoretical dry solids applied, g/m2
COVERAGE
Theoretical coverage, m2/L
Actual coverage, m2/L
COSTS
Cost, US dollars/L on a 208-L basis b
Theoretical cost, US dollars/m*
Actual cost, US dollars/m*
Adhesive 1
1,101
0.4596
48
65
32
15.67
7.79
8.56
0.55
1.10
Adhesive 2
1,085
0.5 146
44
59
32
17.30
9.43
3.88
0.22
0.41
Adhesive 3
1,107
0.5153
74
100
32
17.66
5.71
4.89
0.28
0.86
Control
791
0.1714
6
8
22
6.30
17.99
1.95
0.31
0.11
a Control applied at 22 g/m2 dry adhesive solids per side. Theoretical coverage for the alternatives is calculated to be 32 g/m2
dry adhesive solids applied per side.
" As of October 1996.
1 ft2/gal = 0.025 m2/L.
1 gal = 3.7854 L.
1 ft2 = 0.093 m2.
Equations and Examples for Adhesive 3:
Dry solids applied, g/m2,
per side
COVERAGE
(Total solids deposited, g) / (2 sides) / (surface area per side, m2)
= 74 g / 2 / 0.37 m2
= 100 g/m2
Theoretical coverage, m2/L, = (Weight fraction solids, g/g) * (density, g/L) /
applied @ 32 g/m' dry solids per side (theoretical dry solids applied per side, g/m2)
= (0.5153 g/g)* (1,107 g/L)/32 g/m2
18m2/L
(continued)
G - I
-------
Actual coverage, m2/L
(Weight fraction solids, g/g) * (density, g/L) /
[(dry solids applied, g) / 2 sides / (surface area, m2)]
(0.5153 g/g) * (1107 g/L) / (74 g / 2 / 0.37 m2)
6m2/L
COSTS
Theoretical cost
US dollars/m2
Actual cost,
US dollars/m2
(Cost, US dollars/L on a 208-L basis) / (theoretical coverage, m2/L)
= 4.9$/L/18m2/L
= 0.28 $/m2
(Cost, US dollars/L on a 208-L basis) / (actual coverage, m2/L)
= 4.89 $/L75.71 m2/L
=0.86 $/m2
G-2
------- |