EPA/600/A-96/129
Material Compatibility Evaluations of HFC-245ea, HFC-245fa, HFE-12S,
HFC-236ea, and HFC-236fa
Krich Ratanaphruks", Michael W. Tufts", Angelita S. Ng", and N. Dean Smithb
Abstract
This paper presents data pertaining to stability and material compatibilities determined for HFC-245ca,
HFC-245fa, HFO-236fa, HFC-236ea, and HFE-125. Following ASHRAE guidelines, material compatibility tests
using 11 elastomers, 4 plastics, 5 metals, and 4 desiccants were conducted with the aforementioned refrigerants
both in the presence and absence of a poryolester (POE) lubricant. The metals (copper, steel, aluminum, brass, and
bronze) were found to be compatible with both the refrigerants and POE oil. Three of four MOLSIV* type
desiccants (4A-XH-6, XH-7, and XH-9) yielded no discernible amount of fluoride, while a small amount was found
in 4A-XH-5. However, trace amounts of fluorine-containing byproducts were detected by GC/MS for all four
desiccants. Based on physical characteristics, unsatisfactory performance across all refrigerants with and without
lubricant was found with fluoropolymers, hydrogenated nitrUe butyl rubber, natural rubber, and Neoprene*.
Introduction
Four relatively new hydrofluorocarbons (HFCs) and one hydrofluoroether (HFE) were subjected to sealed
tube stability and compatibility testing with several metals, desiccants, elastomers, and plastics. HFC-245ca has
received attention as a potential alternative for chlorofluorocarbon (CFQ-11 and hydrochlorofluorocarbon
(HCFQ-123 in low pressure chillers. HFC-245& has also been considered for use in chillers and is currently
being evaluated as a blowing agent for polyurethane foams. HFC-236ea has several attributes that make it a strong
contender as an alternative refrigerant for CFC-114 and as a foam blowing agent HFC-236fa is an alternative
refrigerant for CFC-114 in chillers and is also being marketed as a fire extinguishing agent. HFE-125 has
thermophysical properties that make it an excellent candidate alone or blended with other refrigerants to replace R-
502. However, the measured reaction rate of HFE-125 with hydroxyl (OH) radical is sufficiently slow to warrant
some concern about the direct global warming potential of HFE-125.
Results of preliminary studies of the compatibilities of HFC-245ca, HFC-245fe, and HFC-236ea with
selected lubricants and engineering materials common to refrigeration systems have been reported previously.1"3
Investigations of the compatibility of several HCFCs and HFCs (including HFC-245ca) with various motor
materials (e.g., wire coatings, sheet insulation, and tie cords) have been conducted by the Trane Company in work
performed for the Air-Conditioning and Refrigeration Technology Institute (ARTI).4 A similar compatibility study
of these same refrigerants (but excluding HFC-245ca) with elastomers was performed by the University of Akron
for ART!.5 Spauchus Associates also performed sealed tube comparisons of the compatibility of the desiccants with
various lubricants and refrigerants but did not include any of the refrigerants reported here.6 The present study
was undertaken to expand the compatibility database for the propane-based HFCs, In addition, it will help to
determine if commonalities or trends in the compatibilities of these structurally related refrigerants and HFEs exist
which might make future selection of optimum materials easier. An exhaustive survey of the numerous elastomer
formulations, plastics, and desiccants commercially available was not attempted. Motor materials except for
Mylar* also were not included in the matrix of materials examined in this work since the earlier ARTI study
focused on these materials and included HFC-245ca among the refrigerants studied.
Experimental Methods
All refrigerants were obtained commercially from chemical suppliers and were determined to have a
purity greater than 99.5% except some of the HFC-245& samples which had a purity of 98.7%. For all
refrigerants except HFE-125, a fully formulated commercially available polyolester (POE) lubricant with a
viscosity of 68 centistokes (eSt)c was used. A similar commercial lubricant of 32 cSt viscosity was used with the
HFE-125. All lubricants were dried under vacuum to contain no more than 50 ppm water prior to use. Moisture
content in the lubricants was determined by Karl Fischer titration.
As a preliminary evaluation of the thermal and hydrolytic stability of these refrigerants and their
compatibility with common engineering materials, a series of sealed tube samples was prepared. These samples
were subjected to sustained heating for a period of 14 days in accordance with the methods described in
ANSI/ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers) Standard 97-19897.
* Acurex Environmental Corporation, P. O. Box 13109, Research Triangle Paric, NC 27709
* National Risk Management Research Laboratory, U, S. Environmental Protection Agency, Research Triangle Pwk, NC 27711
c2
-------
Thermal stability tests for these refrigerants were carried out with metals at 175°C for 14 days. Compatibility tests
of plastics, desiccants, and elastomers were carried out in an analogous way but at 125 °C. All materials were
tested with refrigerants both in the presence and absence of the POE lubricant Duplicates of each sample
combination were tested. Elastomers were commercially available O-rings (except Geolast® which was obtained as
a 3 mm thick sheet) while plastics were either O-rings (Teflon*) or rectangular strips (Mylar*, Nomex®, nylon 6,6)
cut to a size convenient for insertion into the 7-mm inside diameter borosilicate tubes.
A Hewlett-Packard 5890 Gas Chromatograph equipped with Flame lonization Detector (GC/FTD) and
Chrompack column, a Hewlett-Packard 5970 GC equipped with a Mass Spectroscopy Detector (GC/MSD), and a
Nicolet Magna 550 Fourier Transform Infrared (FilR) Spectrometer interfaced with a Hewlett-Packard 5890
Chromatograph were employed for gas-phase analysis of both fresh and aged refrigerant. Fresh and aged POE
lubricants were analyzed using the Nicolet Magna 550 FTDR. Spectrometer with Horizontal Attenuated Total
Reflectance (FITO/HATR). Conditions for GC/FID measurement were; 40 °C isothermal column temperature, 10
minutes run time, and 10.0 uL sample injection by a 10-pL SGE or Hamilton #1701 gastight syringe.
All dimensional measurements of the elastomers and plastics were made within 12 hours following
removal of the materials from the sealed tubes. Tensile properties (e.g., elongation-to-break) were determined by
an Instron Mini-55 within 24 hours after removal of the materials from the sealed tubes. Weight change was
measured within 30 minutes following removal of the materials from the sealed tubes and is accurate within +0.5
percent. Volume change within +3 percent was determined by measuring the physical dimensions of the materials
with a digital ealiper and applying appropriate mensuration formulae. Linear swell was likewise determined by
dimensional measurement and is deemed accurate to +2 percent Hardness was determined with a Shore M Type
Durometer to within ±2 percent.
Detailed formulations (e.g., percentages of base polymer, fillers, plasticizers, mold release agents,
curatives, and accelerators) for the individual elastomers studied were not available from the supplier. Therefore,
the extent to which variations in the formulations for the elastomers could affect the compatibility results was not
evaluated. It is possible that different formulations for a particular generic type of elastomer could result in slightly
different behavior than reported here. A description of the polymeric materials is given in Table 1.
Evidence for refrigerant degradation was sought by comparison of the infrared spectra and gas
chromatograins of the vapor phase from each of the aged samples against those of unaged refrigerants.
Degradation of aged lubricants in the samples was assessed by infrared spectral comparison with the imaged
lubricant.
Four molecular sieve desiccants (beads) were also tested with the refrigerants and refrigerant/POE oil
mixtures, with the exception of HFE-125. The nominal pore sizes of the molecular sieves are 4.0 A for 4A-XH-5
and 3.0 A for the other desiccants. These desiccants were activated before use by heating in an oven at 275 °C for
at least 2 hours. Specifically, each desiccant type was analyzed for any fluoride content which might have been
deposited as a result of refrigerant degradation during accelerated aging. Fluoride determinations were performed
on the aqueous distillate collected after passing steam over a bed of desiccant mixed with a small amount of
vanadium pentoxide in a nickel tube heated to 975 °C. Fluoride concentrations in the resulting distillates were
measured with a fluoride ion selective electrode.
RESULTS
Metals
None of the five metals (i.e., aluminum, copper, cast iron, brass, and bronze) were found to cause
chemical breakdown within the detection limits of our GC and GC/FTTR instrumentation. Thus, these metals are
deemed to be appropriate for use with the alternative refrigerants and POE lubricant
Desiccants
None of the four desiccants tested contained measurable amounts of fluoride ion prior to aging with the
refrigerants and lubricants. Following the aging process, only 4A-XH5 showed the presence of fluoride ion (< 4
percent). This increase of fluoride content occurred with this desiccant in contact with HFC-245fa, HFC-236fa,
and HFC-236ea, with and without the lubricant present. This result suggests that these refrigerants were slightly
degraded in contact with 4 A-XH-5 but not with the other three desiccants. GC and spectral examination of the
vapor in the tubes following the aging process indicated trace amounts of possible refrigerant degradation products
regardless of the desiccant used. The complete data are shown in Table 2.
Elastomers and Plastics
-------
Infrared spectral changes observed in the liquid phase for some of the samples containing
elastomers/plastics could not be attributed unambiguously to degradation of the elastomers/plastics, lubricant, or
both. The most likely source of these new infrared absorption features seem to be leaching of some components of
the polymeric materials, such as fillers, accelerators, or plasticizers.
In addition to gas and liquid phase analyses, physical characterizations were also performed on the
elastomers and plastics. Tables 3-5 tabulate the observed changes in hardness/weight, elongation-to-break, and
linear swell/volume, respectively, for the elastomers and plastics tested. Values represent averages of the duplicate
samples for each material.
To distinguish the performance of various elastomers and plastics, the set of criteria shown in Table 6
was applied to the data. Some swelling of elastomeric materials is acceptable for gaskets and O-rings to form a
good seal in equipment. However, volume increases of greater than 20 percent or linear swell of greater than 5
percent may be considered excessive and detrimental. Also, any shrinkage of the material is not desired. A
change in hardness of ±10 percent may indicate excessive softening or embrittlement and may be considered
unacceptable. Depending on where in the equipment the engineering materials are placed, the O-ring and gasket
materials may experience contact primarily with the refrigerant or with a combination of refrigerant and lubricant
Therefore, a given elastomer or plastic may be suitable for use in one section of the equipment and not in another.
Although the data are herein analyzed according to the criteria listed in Table 6, readers may wish to select other
values that may be more appropriate for the intended application.
Applying Table 6 criteria, the observed property changes can be plotted as in Figures 1 -10. To simplify
the presentation, these figures show the data for only those materials that performed marginally or unsatisfactorily.
In each of these figures, any percentage change beyond the solid line indicates that the specimen performed
unsatisfactorily, while any percentage change between the solid and dotted lines indicates a marginal performance.
The solid and dotted lines incorporate the uncertainties in measurements with Table 6 criteria. It should be
emphasized that the materials that performed well with the refrigerants and refrigerants combined with POE oil
are not shown in these figures.
Table 4 shows the change in the percent of elongation at the maximum load for each elastomer.
Elongation results are available for all refrigerants except HFC-245fa and HFE-125. In this case, the materials are
evaluated to the point of failure which may be indicative of their structural integrity. The data indicate that the
elastomers in our test matrix, except S-70, experienced some degree of deterioration during the aging process.
These reductions in tensile performance range from 10 percent for Teflon to almost 80 percent for E-70.
CONCLUSIONS
Tables 7 and 8 rate each of the polymers with regard to each criterion (listed in Table 6) as "satisfactory,"
"marginal," or "poor" (blank, O, •, respectively). Based on our criteria, across all refrigerants with and without
lubricant, Buna-N, Geolast, Hypalon, Buna-S, S-70, and E-70 appeared to be acceptable performers overall.
Fluoropolymers, namely, Viton-A, Kalrez-C, and Teflon, were especially susceptible to absorption of the
refrigerants resulting in unacceptable swelling. HNBR and natural rubber showed excessive swelling in the
presence of POE oil. Neoprene was deemed unsuitable due to shrinkage and embrittlement in the presence of
refrigerant with and without POE oil. Thiokol was also examined early in the test program, but was discontinued
because this material easily degraded to the point that measurements could not be performed Therefore, these
materials are probably not suitable for use with these refrigerants/lubricant systems. In contrast, the aluminum,
cast iron, copper, brass, and bronze appeared to work well with all refrigerants and refrigerant/POE oil
combinations. On balance, the MOLSFV desiccants appeared to be compatible with all refrigerants and lubricants
with a possible exception of 4A-XH-5.
Sealed tube compatibility tests such as described here are meant to be only suggestive of possible
incompatibilities La actual practice. However, these results have proven in the past to be helpful in narrowing the
initial choices of engineering materials for operating systems. The final selection of a material is application
specific, and many factors need to be considered, including operating temperature, operating pressure, contact with
other materials, mechanical construction of equipment, expected lifetime, and cost.
References:
1. Smith, N. D., Ratanaphruks, K., Tufts, M. W., and Ng, A. S., R-245ca: A Potential Far-Term Alternative for R-
11, ASHRAE Journal 35, No. 2,19-23, February 1993.
2. Smith, N. D., Ratanaphruks, K., Tufts, M. W., and Ng, A. S., HFC-236ea: A Potential Alternative for CFC-
114, Proceedings of the International CFC and Halon Alternatives Conference, Washington DC, October 20,1993.
-------
3. Smith, N. D., Ng, A. S., Tufts, M. W,, Drago, A. M., and Ratanaphruks, K., Evaluation of HFC-245fa as a
Potential Alternative for CFC-11 in Low Pressure Chillers, Proceedings of the International CFC and Halon
Alternatives Conference, Washington DC, October 24-26,1994.
4, Doerr, R,, and Kujak, S,, Compatibility of Refrigerants and Lubricants with Motor Materials, final report for
ARTIMCLR Project Number 650-50400, U. S. Department of Energy report DOE/CE/23810-13, May 1993.
5. Hamed, G. R., Seiple, R H., and Taikum, O., Compatibility of Refrigerants and Lubricants with Elastomers,
final report for ARTI MCLR Project Number 650-50500, U. S. Department of Energy report DOE/CE/23810-14,
January 1994.
6, Field, J. E., Sealed Tube Comparisons of the Compatibility of Desiccants with Refrigerants and Lubricants,
final report for ARTI MCLR Project Number 650-50500, U. S. Department of Energy report DOE/CE/23810-54,
May 1995.
7. ASHRAE 97-1989, "Sealed Glass Tube Method to Test the Chemical Stability of Material for Use Within
Refrigerant Systems," American Society of Heating, Refrigerating and Air-Conditioning Engineers, 1791 Tullie
Circle, NE» Atlanta, GA, 1989,
Table 1. Description of Polymeric Materials
Materials *
Buna'"-N
E-70orEPDM
Geolast*
HNBR
HYPorHvpalon*
Kalrez*-C
Natural rubber or PG-35
BunaI"-S
Neoprene 3229
S-70orSI
Viton^-A
Mylar*
Nomex*
Nylon 6,6
Teflon*
Description
Copolymer of 1,3-butadieae (70 %) and acrylonitrile (30 %)
Ethylene propyleae diene polymethylene rubber
Nitrile polypropylene
Hydrogenaled nitrite butyl rubber, hydrogenated butadiene acrylonitrile Copolymer
Chlorosulfonated polyethylene
Perfluoropolymer of tetrafluoroethylene and perfluoromethyl vinyl ether
Isoprene polymer
Copolymer of 1,3-butadiene (70-75%) and stymie (25-30%)
Polychloroprene
Silicone rubber
Copolymer of vinylidene fluoride and hexafluoropropylene
Polyethylene teraphthalate
Polymer of m-phenylenediamine and isophthaJic acid chloride
Polymer of adipic acid and hexamethylenediamine
Polymer of tetrafluoroethylene
* Thiokol was also examined early in the test program, but was discontinued because this material easily degraded.
Table 2. Percent Fluoride in Activated Desiccants*
Desiccants
XH-5
XH-6
XH-7
XH-9
% CHANGE WITHOUT POE
HFC
245ca
0
0
0
0
HFC
245fa
2.67
0
0
0
HFC
236fa
1.66
0
0
0
HFC
236ea
3.02
0
0
0
HFE
125
0
0
0
0
% CHANGE WITH POE
HFC
245ca
0
0
0
0
HFC
245fa
2.43
0
0
0
HFC
236fa
0.12
0.30
0
0
HFC
236ea
2.02
0
0
0
HFE
125
0
0
0
0
HFE-125 - no desiccant data available; all desiccants are of the form 8x12 beads.
-------
Table 3. Percent Change in Hardness and Weight for Polymers
Polymers
Buna-N
E-70
HNBR
Hypalon
KalrezC
Nat rubber
Buna-S
Neoprene
S-70
Viton
Geolast
Teflon
Mylar
Nomex
Nylon 6,6
% CHANGE WITHOUT POE
HARDNESS
HFC
245ca
-6.82
2.61
-9.14
1.47
-19.39
-6.87
-2.15
13.88
-5.94
-12.26
-11.24
*
*
*
*
HFC
245fa
9.33
6.08
-6.18
11.69
-19.27
-3.56
2.76
11.16
29.47
-2.74
-10.22
*
*
*
*
HFC
236fa
-4.51
-1.96
-5.91
0.57
-19.64
-5.16
-5.31
5.86
-17.03
-11.33
-6.58
*
*
*
*
HFC
236ea^
-7.51
-8.56
-11.27
0.46
-18.92
-5.87
-1.93
21.09
8.11
-16.47
-1.59
*
*
*
+
HFE
125
20.83
4.47
12.58
10.87
-18.83
-14.30
3.50
11.04
25.25
-9,04
-7.86
*
*
*
*
% CHANGE WITH POE
HARDNESS
HFC
245ca
-6.57
14.96
-9.29
-2.52
-15.11
-23.88
9.67
12.80
-11.55
-12.01
-3.09
*
*
*
+
HFC
245fa
4.55
7.57
7.99
9.49
-17.06
-24.48
14.47
12.80
28.57
-3.84
-9.64
*
*
*
*
HFC
236fa
-5.00
4.61
-8.78
-3.42
-19.53
-40.61
-4.72
3.19
-25.56
-14.45
-5.36
*
*
*
*
HFC
236ea
- 5.59
7.82
-11.52
-3.20
-18.95
-26.78
-1.93
23.09
-0.51
-14.23
4.15
*
*
*
• *
HFE
125
-10.28
-1.32
-2.42
-13.47
-17.52
-50.64
-2.15
5.75
10.15
-15.30
-3.59
*
*
*
*
% CHANGE WITHOUT POE
WEIGHT
HFC
245ea
31.54
5.02
60.98
5.02
41.31
8.34
2.81
3.37
7.92
72.21
41.77
3.19
4.17
-2.45
-2.36
HFC
245fa
8.99
2.46
35.12
4.59
54.19
5.21
2.64
-1.93
1.43
30.53
23.32
2.92
*
*
*
HFC
236fa
9.43
2.06
15.12
1.89
21.10
1.73
3.11
0.99
0.86
18.42
8.50
3.57
1.01
-1.00
2.43
HFC
236ea
26.43
2.40
45.56
3.50
21.46
3.12
2.36
2.22
0.18
31.56
20.14
4.15
2.17
0.13
3.75
HFE
125
2.57
1.38
10.27
0.30
33.11
2.70
2.43
-3.08
2.45
21.96
6.30
6.30
0.61
7.69
-13.20
% CHANGE WITH POE
WEIGHT
HFC
245ca
22.95
-3.45
49.02
9.41
18.93
2.05
-9.01
5.74
9.97
31.53
19.17
2.31
2.55
8.80
-10.77
HFC
245fa
14.52
6.67
31.42
10.21
17.05
22.12
-8.58
2.98
4.00
31.95
16.49
2.42
*
*
*
HFC
236fa
5.85
-3.13
26.33
10.99
20.81
26.17
-1.29
10.02
7.33
24.24
12.61
3.37
0.76
5.62
-12.16
HFC
236ea
12.76
-1.91
48.18
9.48
16.43
20.73
-3.25
5.76
5.71
15.53
9.90
2.99
1.64
8.59
-10.02
HFE
125
24.2?
8.51
26.66
25.65
12.91
12.63
-1.90
-2.61
7.73
47.17
11.12
4.86
0.35
-1.50
0.13
* data not available
Table 4. Percent Change in Elongation for Polymers
Polymers
Buna-N
E-70
HNBR
Hypalon
KalrezC
Nat. rubber
Buna-S
Neoprene
S-70
Viton
Teflon
% CHANGE WITHOUT POE
HFC-24Sca
-17.54
-59.57
-39.16
-52.91
-7.83
-30.92
-33.75
-31.48
17.63
-19.05
-8.30
HFC»24Sfa
*
* '
-27.15
*
-36.53
-42.43
*
*
*
*
*
HFC-236fa
-33.35
-60.19
49,95
-40.44
-34.00
-34.46
-20.33
-64.53
-7.50
-36.79
-30.42
HFC-236ea
-36.90
-62.11
-31.16
-49.22
-31.48
-29.15
-19.49
-42.29
13.05
-40.67
11.33
HFE-125
*
*
*
*
*
*
*
*
*
*
*
% CHANGE WITH POE
HFC-24Sca
-34.74
-77.93
-33.96
-47.37
-20.41
-31.36
-32.91
-41.28
19.00
-10.18
-38.15
HFC-245fa
*
*
*
*
-19.71
-23.83
*
*
*
*
*
HFC-236fa
-38.48
-74.58
-13.54
-42.29
-20.97
-40.66
-37.08
-69.34
24.73
-38.46
-2.20
HFC-236ea
-46.36
-78.17
-23.55
-46.44
-20.55
-34.90
-54.71
-62.13
12.12
-25.15
-13.80
HFE-125
*
*
*
*
*
*
*
*
*
*
#
* Data not available
-------
Table 5. Percent Change in Linear Swell and Volume for Polymers
Polymers
Buna-N
E-70
HNBR
Hypalon
KakezC
Nat rabber
Buna-S
Neoprene
S-70
Viton
Geolast
Teflon
Mylar
Nomex
Nylon 6,6
% CHANGE WITHOUT POE
LINEAR SWILL
HFC
245c«
4.96
1.34
11.29
4.46
14.06
1.49
2.42
1.42
0.71
23.85
7.84
3.41
-1.00
-0.78
-1.72
HFC
245fa
0.46
-1.15
8.62
-1.72
13.75
1.42
-1.26
-2.66
-1.22
12.81
4.74
29.84
*
*
*
HFC
236fa
1.96
1.25
3.46
1.20
8.84
1.31
1.26
1.86
0.10
6.16
2.55
2.96
-1.10
-0.36
0.46
HFC
236ea
5.51
1.19
9.35
2.34
8.26
1.32
^ 1.33
0.87
-0.11
8.77
3.32
3.94
-1.05
-0.39
0.23
HF1
125
-1.77
-0.03
2.72
-0.44
17.02
1.07
-0.33
-2.14
-0.11
6.51
0.91
2.02
-1.19
-0.92
-4.94
% CHANGE WITH POE
LINEAR SWELL
HFC
245ca
5.52
-2.75
10.92
6.65
10.10
7.73
-1.55
3.80
LOO
12.51
3,53
3.94
-1.12
-0.60
-4.18
HFC
245fa
2.03
0.88
7.83
2.81
6.50
6.34
-3.54
-0.38
1.33
11.47
3.63
27.22
*
*
*
HFC
236fa
1.33
-0.76
6.85
4.80
8.17
8.30
-0.06
5.50
2.62
9.37
1.43
2.98
-1.13
-0.83
-4.34
HFC
236ea
2.73
-0.77
10.84
4.07
6.50
6.91
-0.02
1.64
2.52
5.55
1.93
2.88
-1.11
-0.70
-3.87
HF1
125
5.01
1.86
7.29
8.96
4.54
2.42
-2.17
-0.89
2.67
16.96
0,91
0.94
-1.28
-0.54
-0.57
% CHANGE WITHOUT POE
VOLUME
HFC
245ca
6.46
7.83
47.18
-2.25
28.11
7.77
12.93
-7.31
-5.27
84.36
27.55
-4.78
11.62
-2.46
-13.71
HFC
245fa
2.70
-0.61
27.63
24.94
49,68
5.97
-4.32
14.36
-11.40
17.89
11.59
3.08
*
+
*
HFC
236fa
4.23
2.25
11.91
0.70
25.04
3.29
2.13
2.81
2.36
16.95
8.36
7.97
6.60
5.20
1.29
HFC
236ea
16.51
0.77
27.18
5.64
30.67
3.56
3.96
3.67
-2.56
25.14
19.13
8.38
2.71
2.77
3.38
HFE
125
4.61
8.43
13.36
7.85
59.86
7.82
11.20
4.89
5.81
29.63
2.22
9.26
-4.85
-1.71
-14.70
% CHANGE WITH POE
VOLUME
HFC
245ca
-4.83
-17.10
35.77
19.95
3.76
23.31
-7.38
-5.71
-9.88
J9.72
14.29
-4.67
2.35
-3.99
-12.88
HFC
245fa
-1.37
4.45
18.04
16.36
26.74
21.68
8.54
J29.17
-2.66
9,78
10.02
2.80
*
*
*
HFC
236fa
4.20
-4.39
18.89
13.95
28.38
25.44
-1.34
14.48
6.62
27.59
2.92
8.76
-4.91
4.16
-12.13
HFC
236ea
7.91
-4.49
33.56
11.24
26.60
20.74
-0.52
5.52
4.20
17.54
9.20
5.56
3.77
-3.82
-9.49
HFE
125
10.43
6.63
28.16
31.19
15.66
-6.67
3.51
-13.07
4.52
48.97
7.93
2.94
0.17
3.27
-2.04
1 Data not available
-------
Table 6. Performance Criteria and Measurement Uncertainties for Polymers
Parameter*
Unsatisfactory
Marginal
Good
Uncertainties
Hardness
±2%
Volume
±3%
Linear Swell
0%:Sx;>+5%
±2%
Elongation
•40%«Sx2»-MO%
±8%
Weight
-20% Sx 2> +20%
-12% fix £+12%
±0.5%
Table 7. Snmmaiy of Elongation Performance Based on Criteria in Table 6
Polymers
Buna-N
E-70
HNBR
Hypalon
KalrezC
Nat rubber
3una-S
Neoprene
S-70
Viton
Geolast
Teflon
HFC- HFC- HFC- HFC- HFE-
245ca 245fa 236fa 236e« 125
(blank = satisfectory, O = marginal, * = poor). * Data not available
-------
Table 8. Performance Summaiy of Polymers Based on Criteria Specified in Table 6
HFC- HFC- HFC- HFC- HFI-
245ca 245fa 236fa 236ea 125
HFC HFC- HFC- HFC- HFE-1
245ca 245fa 236fa 236ea 125
Buna-N
E-70
HNBR
Hypaloa
KalrezC
Nat. rubber
Buna-S
Meoprene
S-70
Viton
Geolast
leflon
Mylar
Nomex
Nylon 6,6
Buna-N
E-70
EDSIBR
Sypalon
SalrezC
STat. Rubber
3una-S
^Jeoprene
5-70
3eolast
refloa
vlylar
tfomex
'Jyloa 6,6
(blank - satisfactory, O = marginal, • = poor). * Data not available
-------
l
ll
|£
if
l!
II
S JBi
9*9HOiXN
KMBON
*fn
UOJS1 -
isajoso
uw«A
Oi-S
KQjdoJN
s-n»a
«JH"«i»H
O=ips
uopcUH
HONH
«t-a
n«na
%e
!l
13
|g
i e<
2 *
II
ss
^ l
D —«
ii
w «
»1
« B
i£
it
is
8 2 2
fim
aawi
""S'i 51
fi
I':
1
LI
KBOi
w-s
«V«H
ttaNH
ot-a
o m o
-------
Figure 5. Vohnne Cfcaafaof Ebaiomtn »od Pladie* Oat Deoteiiitrated Marftnal or
UnmtMactorf Performance after Exponre to Refllg«i«irt
30
20-
i]
-10 •
.JO.
-30 J
• HF&245C*
D HFC445&
BHF&236A
DKFC-Z36M
OHFE.125
1
Figure 7, Hurdinn Cbaap of Ebutomtn tfait Dcniointntod Msrgtnul or
P»ifonniuic* alter Exposure to Befrigerant
Flgar* 6. Vohnne Change of Elaftomm and Phutlca that Demonstrated Marginal or
Vauitifttctarf PerforaiaiKa after Etpoun to Eefrlgeraiit and POE Lubricant
—i-—n jLJl
—— .inrifM., • -.,,*— —- , , 1,, Li ..-4 »-•..-..-. I ^,,,,.-, _., 4 • „„! 4 •.,„ L
|
. Hurdans Chanf§ oC Elntmin ttnrt Dtmoaftratod M*i
Ptrformum after Expoton to RctHgtrrat «nd FOE Lubricant
-------
OO'OOI-
OO'OI
OO'OOl-
ODDS'
OOW-
WW-
W05-
OO'O
OO'OZ
-------
4. TITLE AND SUBTITLE
Material Compatibility Evaluations of HFO245ea,
HFC-245fa, HFE-125, HFC-236ea, and HFC-236fa
NRMRL-RTP-P-146
TECHNICAL REPORT DATA
(Please read Itatmetions on the reverse before completing
1. REPORT NO.
EPA/600/A-96/129
2.
I. RE
PB97-193619
S. REPORT DATE
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
8. PERFORMING ORGANIZATION REPORT NO.
K.Ratanaphruks, M. Tufts, A. Ng (A cur ex); and
D. Smith (EPA. NRMRL-RTP)
fl. PERFORMING ORGANIZATION NAME AND ADDRESS
A cur ex Environmental Corporation
P. O. Box 13109
Research Triangle Park, North Carolina
10. PROGRAM ELEMENT NO,
27709
11. CONTRACT/GRANT NO.
68-D4-0005
12. SPONSORING AGENCY NAME AND ADDRESS
EPA, Office of Research and Development
Air Pollution Prevention and Control Division
Research Triangle Park, NC 27711
13. TYPE OF REPORT AND PERIOD COVERED
Published paper; 10/94-8/96
14. SPONSORING AGENCY CODE
EPA/600/13
ie. SUPPLEMENTARY NOTESAPPCD project officer is N. Dean Smith, Mail Drop 63, 919/541-
2708. Presented at International Conference of Ozone Protection Technology, 10/21-
23/96, Washington, DC.
16. ABSTRACT
paper presents data pertaining to stability and material compatibilities
determined for HFC-245ca, HFC~245fa. HFE-125, HFC-236ea, and HFC-236fa. Fol-
lowing ASHRAE guidelines, material compatibility tests using 11 elastomers, 4 plas-
tics, 5 metals, and 4 desiccants were conducted with the aforementioned refriger-
ants in both the presence and the absence of a polyolester (PCE) lubricant. The me-
tals (cupper, steel, aluminum, brass, and bronze) were found to be compatible with
both the refrigerants and the POE oil. Three of four MGLSIV desiccants (4A-XH-6,
XH-7, and XH-9) yielded no discernible amount of fluoride, while a small amount
was found in 4A-XH-5. However, trace amounts of fluorine- containing byproducts
were detected by gas chromatography/mass spectroscopy for all four desiccants.
Based on physical characteristics, unsatisfactory performance across all refriger-
ants with and without lubricant was found with fluoropolymers, hydrogenated nitrile
butyl rubber, natural rubber, and Neoprene.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
COSATI Field/Group
Pollution
Refrigerants
Propane
Halohydrocarbons
Ethers
Metals
Desiccants
Plastics
Pollution Prevention
Stationary Sources
Material Compatibility
Hydrofluorocarbons
Hydrofluoroethers
13 B
13A
07C
111
11F 07B
11G
18. DISTRIBUTION STATEMENT
Release to Public
19. SECURITY CLASS (This Report}
Unclassified
21. NO. OF PAGES
20. SECURITY CLASS (This page)
Unclassified
22. PRICE
EPA Form 2220-1 (9-73)
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