as PTFE, it has excellent resistance to chemical at-
and Barcelona et al. (1985) and Curran and
tack by corrosive reagents and dissolution by sol-
Tomson (1983) for PTFE. Presumably FEP would
vents (Nalge 1994) (App. B). FRE is composed of
perform similarly to PTFE.
75% silica glass and 25% closed molecular epoxy,
We concluded that FRE looked like the most
and according to its manufacturer is impervious
promising material for monitoring organics and
to gasoline, hydrocarbon products, and most sol-
that ABS should not be used when monitoring or-
vents and additives. The Cole-Parmer catalog
ganics. However, any material that is going to be
(1992) appears to support this claim for hydrocar-
used for monitoring organic contaminants should
bons but not for all solvents. They report that
also be relatively resistant to degradation by a wide
"epoxy" has good resistance to fuel oils, gasoline,
range of organic compounds and should ideally
jet fuel, and kerosene. However, they also report
be able to withstand acidic and alkaline environ-
that epoxy is moderately affected by several ke-
ments. This study compares the susceptibility of
tones and is severely degraded by dichloroeth-
ABS, FEP, FRE, FRP, PVC, and PTFE to degradation
ane, dimethyl formamide, benzaldehyde, and
by organic solvents and extremely acidic and alka-
others. (See App. A for a more extensive listing.)
line conditions.
ABS is a terpolymer of acrylonitrile, butadiene,
and styrene. According to the Cole-Parmer cata-
log (1992), it is severely degraded by a number of
LITERATURE REVIEW
organic chemicals, including several ketones,
chlorinated alkanes and alkenes, and several hy-
Information on the ability of these materials to
drocarbons such as fuel oils, gasoline, and kero-
resist chemical degradation is sketchy. Most of
sene. (See App. A for a more extensive listing.)
the information we found was either provided by
However, it is important to note that the Cole-
the manufacturer or taken from the Cole-Parmer
Parmer catalog does not give any detail on the
catalog (1992) or the Nalge catalog (1994). FEP is
type of epoxy or ABS materials that were tested.
a copolymer of tetrafluoroethylene and hexafluoro-
FRP is composed of 70% fiberglass and 30%
propylene, and like other fluoropolymers, such
Table 1. Chemicals used in testing polymeric materials for weight
gain and degradation (swelling/softening, dissolution).
Hydrocarbons (aliphatic & aromatic)
Benzene
Kerosene (K-1)
Gasoline (93 octane, unleaded)
Toluene
Hexane (85% N-hexane)
o-xylene
Chlorinated solvents (aliphatic & aromatic)
Bromochloromethane
1,2-dichloroethane
Carbon tetrachloride
trans-1,2-dichloroethylene
Chlorobenzene
Methylene chloride
Chloroform
Tetrachloroethylene
1,2-dichlorobenzene
Trichloroethylene
Oxygen-containing compounds
(either a ketone, alcohol, aldehyde, or ether)
Acetone
Methyl alcohol
Benzaldehyde
Methyl ethyl ketone
Benzyl alcohol
Tetrahydrofuran
Cyclohexanone
Nitrogen-containing compounds
N-butylamine
Dimethylformamide
Diethylamine
Nitrobenzene
Acids and bases
Acetic acid (glacial)
Sodium hydroxide (25% w/v)
Hydrochloric acid (25% w/v)
2
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