Butyl
IIR (isobutylene-isoprene) |
+
|
Excellent
resistance to acids and alkalis.
Excellent
weathering properties and heat resistance.
Excellent electrical resistance. Low permeability to air.
|
| |
-
|
Poor
resistance to fuels, solvents, oils and hydrocarbons.
Cold weather properties are fair.
|
|
CPE
(Chlorinated Polyethylene) |
+
|
Excellent
oxidation resistance.
Good oil resistance, heat resistance, ozone resistance and
weather resistance.
Fair resistance to ketones and ethers.
|
| |
-
|
Poor
cold weather properties. |
|
EPDM
(ethylene-propylene diene) |
+
|
Excellent resistance to ozone, sunlight and oxygen.
Excellent resistance to acids, alkalis and ketones.
Excellent heat resistance and aging.
|
| |
-
|
Poor
resistance to fuels and oils. |
|
Fluoroelastomer
(VITON fluroelastomer, a registered trademark of DuPont Dow
Elastomers) |
+
|
Excellent resistance to heat and oil combinations: hot greases
found in engines and compressors.
Excellent resistance to a wide range of concentrated acids.
|
| |
-
|
High
cost of fluoroelastomer may limit usage to extreme applications.
Resilience is low and tear strength is limited unless certain
compounding steps are taken to improve it. Impact resistance
is fair. |
|
SBR
(Styrene butadiene) |
+
|
Good
abrasion resistance and excellent impact and cut-and-gouge
resistance. Can be compounded for use as skirtboard rubber,
lining
rubber, conveyor belt covers, tires and other extremely demanding
applications. Used as gasket material and as an economical
general purpose sheet.
|
| |
-
|
Not
suited for use with oils, fuels, solvents, or hydraulic fluids.
|
|
Silicone
|
+
|
Excellent
properties for both hot and cold temperature extremes; excellent
weathering properties; resists ozone and oxygen attack. Long
service life can be expected at 200°F to 400°F (93°C
to 204°C). |
| |
-
|
Poor
resistance to oils, fuels, and hydrocarbons. Fair performance
when exposed to acids, alkalis and solvents. Physical properties
(tensile, abrasion, tear and cut growth) are fair. |
|
Natural
Rubber
NR (Gum) |
+
|
Good
gasket material due to excellent physical properties such
as resilience, tear strength and wear resistance. Natural
rubber is used effectively
as sand and shot blast curtain material because of its high
abrasion resistance and resilience.
|
| |
-
|
Deteriorates
when exposed to oils, fuels, solvents, and hydraulic fluids.
Poor resistance to sunlight, ozone and oxygen. |
|
Neoprene
CR (chloroprene) |
+
|
Good
oil- and petroleum-based solvent resistance. Good weather and
ozone resistance. Neoprene may be blended with SBR rubberto
achieve an economically priced sheet for moderately oil resistant
applications. |
| |
-
|
Poor
resistance to degreaser solvents. Content levels of neoprene
can vary widely. Application problems may occur when using
blended or commercial grades of neoprene sheet of unknown
quality levels in contact with oil, solvents and fuels.
Where
good oil or fuel resistance is required, the fabricator and
user need to specify one of the following:
•
A known manufacturer's product
•
An ASTM call-out
•
A military specification
•
An ASTM-specified oil resistance level based on an
ASTM
test (e.g. oil swell)
|
|
Nitrile
(butadiene-acrylonitrile) |
+
|
Excellent
resistance to oils, solvents and fuels.
Resistant
to a broader range of aromatic hydrocarbons than neo- prene.
Nitrile may be blended with SBR rubber to achieve an economically
priced sheet for moderately oil resistant applications.
|
| |
-
|
Application
problems may occur when using nitrile of unknown quality levels
in extreme oil resistance applications or in contact with
fuels and solvents.
Content levels of nitrile can vary widely.
Where oil or fuel resistance is required, the fabricator and
user need to specify one of the following:
•
A known manufacturer's product
•
An ASTM call-out
•
A military specification
• An ASTM-specified oil resistance level based on an
ASTM test (e.g. oil swell)
|
| |
|
|
