Table 6. Percentage weight gain of PVC exposed to chemical treatment.
Contact time (days)
Chemical
1
7
14
21
28
56
112
Acetic acid (glacial)
0.1
0.1
0.2
0.2
0.3
0.2
0.4
142.6s
Acetone
145.5
146.7
151.4
156.4
157.3
157.8
100.9s
Benzaldehyde
D
29.7s
Benzene
7.2
45.4
49.5
49.2
48.8
48.7
Benzyl alcohol
0.0
0.0
0.1
0.1
0.1
0.1
0.1
Bromochloromethane
D
63.8s
N-butylamine
111.0
110.7
D
Carbon tetrachloride
0.0
0.1
0.0
0.1
0.1
0.1
0.1
57.2s
Chlorobenzene
151.1
153.0
156.6
157.3
158.8
159.8
144.2s
Chloroform
216.1
218.2
221.9
220.3
222.8
223.9
Cyclohexanone
D
16.8s
1,2-dichlorobenzene
73.5
134.3
206.6
208.6
214.5
217.7
206.6s
1,2-dichloroethane
352.4
D
49.6s
trans-1,2-dichloroethylene
57.7
57.5
56.2
56.2
56.0
56.3
31.8s
Diethylamine
2.5
8.7
13.8
17.2
20.4
23.9
Dimethylformamide
D
Gasoline (93 octane, unleaded)
0.0
0.0
0.2
0.0
0.0
0.0
0.1
Hexane (85% N-hexane)
0.0
0.0
0.0
0.1
0.1
0.1
0.1
Hydrochloric acid (25% w/v)
0.2
0.2
0.1
0.1
0.0
0.1
0.3
Kerosene (K-1)
0.1
0.1
0.0
0.0
0.0
0.0
0.0
Methyl alcohol
0.4
0.1
0.2
0.2
0.2
0.3
0.4
298.9s
Methyl ethyl ketone
D
454.9s
Methylene chloride
D
138.1s
Nitrobenzene
D
Sodium hydroxide (25% w/v)
0.0
0.0
0.1
0.2
0.1
0.1
0.1
Tetrachloroethylene
0.1
0.4
0.6
0.7
0.8
1.2
1.7
Tetrahydrofuran
D
38.4s
Toluene
10.5
51.6
50.9
50.7
50.6
51.4
34.9s
Trichloroethylene
71.3
72.8
70.1
71.0
70.5
70.9
11.7s
o-xylene
3.8
17.1
23.0
28.2
44.4
65.7
D dissolved or disintegrated upon handling
s first observation of swelling and/or softening
ratings given by Cole-Parmer and Nalge compa-
ABS was by far the most readily degraded
nies, we developed the following classification
polymer. After only one day, nineteen of the
scheme for our data:
thirty chemicals tested either dissolved ABS or
A. Excellent. Any chemical that had little or no
softened it to the point where it fell apart (Table
effect on the material, i.e., where the change in
7). Four other chemicals caused either softening
weight was 1% or less.
or swelling of the test coupon on the first day. By
the end of the study, only the acid and alkali solu-
B. Good. Any chemical that had only a minor
tions had little effect (~1% weight gain). While
effect, i.e., there was no observable effect except
for a slight change in weight (from 1 to 5%).
ABS is susceptible to organic solvents in general,
C. Moderate effect. Those chemicals that caused
it is especially susceptible to polar solvents.*
more than a 5% change in weight with no other
Clearly, ABS is a poor choice where exposure to
observable changes.
neat organic solvents may be involved.
D. Unacceptable. Any chemical that caused the
Table 8 compares the chemical resistance rat-
material to swell, soften, dissolve, delaminate, or
ings from the Cole-Parmer catalog and the Nalge
that caused particles to fall off.
catalog with our (CRREL) findings. In order to
While we realize that our rating system was
compare our results with the chemical resistance
totally arbitrary, we generally had good agree-
ment between our results and those given in the
Cole-Parmer catalog. This was especially true for
* Personal communication, Daniel C. Leggett, Research
PTFE and ABS. For these materials there were
Chemist, CRREL, 1994.
7
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