RESIDUAL MONOMERS IN ACRYLIC AND
MODACRYLIC FIBERS AND FABRICS
FINAL REPORT
Contract No. 68-01-4746
Task Order No. 3
OFFICE OF TOXIC SUBSTANCES
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
Washington, D. C. 20460
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EPA Report No,
July 1979
RESIDUAL MONOMERS IN ACRYLIC AND
MODACRYLIC FIBERS AND FABRICS
by
Joe M. Finkel
Ruby H. James
Herbert C. Miller
Southern Research Institute
2000 Ninth Avenue South
Birmingham, Alabama 35205
Contract No. 68-01-4746
Task Order No. 3
Project Officer: James Darr
Prepared for
OFFICE OF TOXIC SUBSTANCES
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
401 M Street, S.W. (TS-792)
Washington, D. C. 20460
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DISCLAIMER
This report has been reviewed by the Office of Toxic
Substances, U.S. Environmental Protection Agency, and
approved for publication. Approval does not 'signify that
the contents necessarily reflect the views and policies
of the U.S. Environmental Protection Agency, nor does
mention of trade names or commercial products constitute
endorsement or recommendation for use.
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PREFACE
This report describes a study conducted under Task
Order No. 3 of the U.S. Environmental Protection Agency
Contract No. 68-01-4746. This effort was part of an
overall service performed under task requests to generate
analytical data on a specified chemical, a group of
chemicals, or commercial products by conducting spe-
cific tests, analyses, or experiments within several
broad areas of interest.
111
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TABLE OF CONTENTS
Page
SECTION 1 INTRODUCTION 1
SECTION 2 CONCLUSIONS 2
SECTION 3 RECOMMENDATIONS 3
SECTION 4 EXPERIMENTAL PROCEDURES 4
EVOLUTION APPARATUS 4
EVOLUTION, ADSORPTION, AND DESORPTION
OF MONOMERS 4
GAS CHROMATOGRAPHIC ANALYSIS 6
DIRECT INSERTION MASS SPECTRAL ANALYSIS . . 7
SECTION 5 EXPERIMENTAL RESULTS 8
EPA Form 2220-1 10
IV
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SECTION 1
INTRODUCTION
This report deals with the detection and quantitation
of acrylonitrile, vinylidene chloride, and vinyl bromide, which
are used as monomers in the production of acrylic and modacrylic
fibers. These three monomers were selected for study because
of concern over their adverse health effects (e.g., their poten-
tial carcinogenicity).
The task order for the analytical work described in this
report called for the detection and quantitation of specific
residual monomers in six samples of materials furnished by the
Environmental Protection Agency. The samples were labeled Blue
Carpet, Yellow Carpet, Brown Carpet, Fiber A, Fiber M, and Blue
Fabric. The samples representing three types of products—car-
pets, fibers and fabrics—were analyzed for acrylonitrile,
vinylidene chloride, and vinyl bromide by gas chromatography
with a flame ionization detector and by direct insertion probe
mass spectrometry.
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SECTION 2
CONCLUSIONS
The results of the gas chromatographic studies indicate
that detectable amounts of residual acrylonitrile, vinylidene
chloride, and vinyl bromide are not released from the carpet,
fiber, and fabric samples under the conditions selected for
analysis. On the other hand, analysis of the six samples by
direct insertion mass spectrometry indicate that methyl bro-
mide is evolved from the Yellow Carpet, Brown Carpet, Fiber A,
and Fiber M. Three halogenated compounds—dibromodichloro-
ethanol, tetrabromoethanol, and tribromochloroethanol—were
identified from one sample, Blue Fabric. Traces of fatty acids
were found in all of the samples, and sulfur dioxide was found
in all of the samples except the Blue Fabric.
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SECTION 3
RECOMMENDATIONS
Because of the potential toxicity of methyl bromide, addi-
tional studies are recommended to quantify the amounts that
were identified in some of the samples. Methyl bromide is a
potent fumigant gas, and it is one of the most toxic of the
common alkyl halides.1 Death following acute poisoning is
usually caused by the irritating effect of methyl bromide on
the lungs. In chronic poisoning, death is due to the toxic
effect of methyl bromide on the central nervous system. Fatal
poisoning in man has always resulted from exposures to relatively
high concentrations of methyl bromide vapors (8,600 to 60,000
ppm), whereas nonfatal poisoning has resulted from exposure
to concentrations as low as 100 to 500 ppm. Locally, methyl
bromide is an extreme irritant to the skin.
In future work, an analytical procedure for the detection
and quantitation of methyl bromide could be based on Sampling
and Analysis Method No. S-372 developed by the National Insti-
tute for Occupational Safety and Health.2 In this procedure,
the evolved gas is sorbed on charcoal, desorbed with carbon
disulfide, and analyzed by gas chromatography.
*Sax, N. I. Dangerous Properties of Industrial Materials.
5th ed. Van Nostrand Reinhold Co., New York, 1979 p. 810.
2NIOSH Manual of Analytical Methods, Vol. 3, Part II, 2nd ed.
National Institute for Occupational Safety and Health, Cincin-
nati, Ohio, 1977. Method Number S-372.
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SECTION 4
EXPERIMENTAL PROCEDURES
EVOLUTION APPARATUS
The apparatus that was constructed to simulate environ-
mental conditions for the collection of residual monomers
evolved from the carpet, fiber, and fabric samples is illus-
trated in the figure on page 5. The insulated air chamber was
a Styrofoam ice chest containing a light bulb as a heat source
and a paddle-blade fan to circulate the warmed air through the
chamber. Temperature was controlled by a Matheson Labstat.
The specimen chamber was connected to a charcoal prefilter and
a humidifier at the inlet side, and a charcoal sorbent tube
was located at the outlet side for collection of monomer vapor.
The chamber temperature was maintained at 50 °C, and the rela-
tive humidity of the air within the chamber was 50%. Air was
drawn through the chamber and through the sorbent tube at
1.2 L/min. The conditions within the chamber were selected
because they probably represent the most adverse conditions
that carpets, fibers, and fabrics may be exposed to in their
natural environment.
EVOLUTION, ADSORPTION, AND DESORPTION OF MONOMERS
Weighed portions of the samples furnished by EPA were
equilibrated for 30 min at 50 °C in the all-glass specimen cham-
ber. Subsequently, moistened air was swept through the speci-
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CHARCOAL
PREFILTER
INSULATED AIR CHAMBER
T
WATER
HUMIDIFIERS
STOP
COCK
WATER
HEAT
SOURCE
FAN
THERMOMETER
o o
o
LAB-STAT
CHARCOAL
SORBENT
TUBE
wt itIMII in.
SENSING
ELECTRODE
linitTTTITIIIH THI 1
TO VACUUM
PUMP
Schematic Diagram of the Monomer Evolution Apparatus
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men chamber and then the sorbent tube. The evolved gases were
adsorbed on chromotographic grade, activated charcoal (Applied
Science Laboratories, Inc., State College, Pa.) packed in the
sorbent tube. After collection of the sample, the adsorbed
volatiles were extracted from the charcoal with 1 mL of methanol,
and aliquots of the extract were analyzed for acrylonitrile,
vinylidene chloride, and vinyl bromide by gas chromotography.
GAS CHROMATOGRAPHIC ANALYSIS
The gas chromatographic analyses were performed with a
Per kin-Elmer Model 910 gas chromatograph equipped with a flame
ionization detector. Separation of the monomers was performed
on a 1.8 m x 2 mm (i.d.) glass column packed with Chromosorb 101.
A temperature program was used in which the initial temperature
was maintained for 4 min at 75 °C, then increased at 5 °C per
min to a final temperature of 120 °C, and held at 120 °C for
2 min. Injector and detector temperatures were both 120 °C.
Nitrogen was used as the carrier gas at a flow rate of 20 mL/min.
Under these conditions, the limits of detection for acryloni-
trile, vinylidene chloride, and vinyl bromide were typically
1, 2, and 2 ng, respectively, at a signal-to-noise ratio of
2 to 1. As explained on page 8 of this report, the limits of
detection are equivalent to 0.02 and 0.04 ppm of monomer in a
10-g sample of polymer.
The gas chromatograph was calibrated by injecting stan-
dard solutions of acrylonitrile, vinylidene chloride, and vinyl
bromide. The following retention times were typical: acryloni-
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trile, 12.4 min; vinylidene chloride, 11.4 min; and vinyl
bromide, 8.8 min.
DIRECT INSERTION MASS SPECTRAL ANALYSIS
Mass spectral measurements were made by the direct inser-
tion technique with a Varian MAT 311A mass spectrometer. Use of
the direct insertion technique involves the introduction of a
small portion of the sample, as is, into the ion source of the
mass spectrometer. The technique may be used with or without
temperature programming. Since many factors affect the intensi-
ties of the peaks, the technique is not strictly quantitative;
however, the limit of sensitivity of the method is in the subnano-
gram to nanogram range. In this manner, the fibers of each sample
were introduced into the mass spectrometer under a reduced pressure
of about 1 x 10~6 torr. The spectra were recorded at probe tem-
peratures ranging from 20 to 300 °C. All compounds that were
identified were evolved at temperatures as low as 20 °C and the
amounts evolved increased with increasing temperatures until the
quantities present were depleted.
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SECTION 5
EXPERIMENTAL RESULTS
Gas chromatography and direct insertion mass spectrome-
try indicated that acrylonitrile, vinylidene chloride, and
vinyl bromide were not evolved in detectable amounts from any
of the six samples of carpets, fibers, and fabric furnished
by EPA. The minimum detectable amounts of the monomers were
1, 2, and 2 ng for acrylonitrile, vinylidene chloride, and
vinyl bromide, respectively, by gas chromatography. These
values correspond to detection limits of 0.02 or 0.04 ppm of
monomer in a 10-g sample of polymer.*
Direct insertion mass spectrometry, however, did reveal
the presence of methyl bromide in four of the samples: Yellow
Carpet, Brown Carpet, Fiber A, and Fiber M. Also, three halo-
genated compounds—dibromodichloroethanol, tetrabromoethanol,
and tribromochloroethanol—were identified in one sample, Blue
Fabric. Traces of palmitic and stearic acids were found in
all of the samples. Sulfur dioxide was also found in all of
the samples except the Blue Fabric.
*The maximum volume of methanol in which 1 or 2 ng of monomer
could be detected was 5 uL. The total volume of methanol
extractant was 1 mL. Thus, the minimum quantity of monomer
in the methanol that could be accounted for was 0.2 or 0.4 ug,
representing 0.02 or 0.04 ppm of the polymer.
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All of the organic halides were observed at a probe tem-
perature of 20 °C and, therefore, do not appear to be thermal
decomposition products. The halogenated ethanols evolved from
the sample may have been hydrolysis products of flame retardants
At this time, an explanation for the presence of methyl bromide,
a fumigant, is not available. A possible source of the fatty
acids is the esters that may have been used as spin finish
agents during the manufacture of the fibers. The sulfur diox-
ide may have resulted from an anti-oxidant formulation.
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1. REPORT NO.
2.
3. RECIPIENT'S ACCESSION-NO.
4. TITLE AND SUBTITLE
RESIDUAL MONOMERS IN ACRYLIC AND MODACRYLIC
FIBERS AND FABRICS
EPORT DATE
July T.979
6. PERFORMING ORGANIZATION CODE
SORI-EAS-79-504
7. AUTHOR(S)
Joe M. Finkel, Ruby H. James, Herbert C,
8. PERFORMING ORGANIZATION REPORT NO.
Miller Project 4045-T3-XV
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Southern Research Institute
2000 Ninth Avenue South
Birmingham, Alabama 35205
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
68-01-4746, Task 3
12. SPONSORING AGENCY NAME AND ADDRESS
EPA, Office of Toxic Substances
401 M Street, S.W. (TS-792)
Washington, D. C. 20460
13. TYPE OF REPORT AND PERIOD COVERED
14. SPONSORING AGENCY CODE
15. SUPPLEMENTARY NOTES
Project Officer is James Darr (TS-792)
16. ABSTRACT
The report deals with the detection and quantitation of acryloni-
trile, vinylidene chloride, and vinyl bromide, which are used as
monomers in the production of acrylic and modacrylic fibers. The
amounts of monomers evolved from samples of carpets, fibers, and fab-
rics at 50 °C and 50% relative humidity were determined by gas chroma-
tography with a flame ionization detector and by direct insertion probe
mass spectroscopy. The results of the gas chromatographic studies indi-
cate that detectable amounts of residual acrylonitrile, vinylidene
chloride, and vinyl bromide were not released from, the carpet, fiber,
and fiber samples under the conditions selected for analysis. Direct
insertion mass spectrometry indicated that methyl bromide was evolved
from all of the fiber samples and from two of the three carpet samples.
From the remaining carpet sample, three halogenated compounds—dibromo-
dichloroethanol, tetrabromoethanol, and tribromochloroethanol—were
identified. Traces of fatty acids were found in all of the samples, and
sulfur dioxide was evolved from all of the samples except the fabric
sample.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS C. COS AT I Field/Group
8. DISTRIBUTION STATEMENT
Unlimited
19. SECURITY CLASS (This Report)
Unclassified
21. NO. OF PAGES
14
20. SECURITY CLASS (Thispage)
Unclassified
22. PRICE
EPA Form 2220-1 (9-73)
10
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