Palram PALSU - Manual (Page 37)

PALSUN® Technical Guide
37
Chemical Resistance
PALSUN sheets are compatible with many materials and chemicals, show limited resistance to others, and are incompatible with a third
group, with which contact may be devastating. The mechanism of chemical attack on polycarbonate sheets differs significantly from
the mechanism of corrosion of metals. Corrosion of metals results in a gradual loss of surface material as a result of electrolytic action
by the relevant chemicals. In the cases where chemical attack on polycarbonate sheet occurs, all or a portion of a range of effects can
be observed. Ethylene choride, chloroform, tetrachloroethane, m-cresol, pyridene and other chemicals can cause partial dissolution
of polycarbonate. Swelling agents include benze, chlorobenzene, tetralin, acetone, ethyl acetate, acetonitrile and carbontetrachloride.
Additional effects include color change and/or whitening. These effects may not always lead to product failure, especially for non-
loaded sheets. Nevertheless, the level of measured mechanical properties will be reduced. The most critical effect of chemical attack is
stress cracking or crazing, which may range in size from being visible to the naked eye to being only observable under a microscope.
Stress cracks will always result in sheet failure which will eminate from areas of greatest stress (screws, fixings, bends, etc.).
Polycarbonate sheets are generally not recommended for use with acetone, ketones, ethers, and aromatic and chlorinated hydrocarbons
in addition to aqueous or alcoholic alkaline solutions, ammonia gas and its solutions and amines.
Polycarbonate is resistant to mineral acids, many organic acids, oxidizing and reducing agents, neutral and acid salt solutions, many
greases, waxes and oils, saturated, aliphatic and cycloaliphatic hydrocarbons and alcohols, with the exception of methol alcohol. The
resistance of polycarbonate to water may be described as good up to approximately 60 °C. At higher temperatures, degradation
occurs, the extent of which depends on time and temperature. Polycarbonate should therefore not be exposed for long periods of
time to hot water. However, brief contact with hot water has no effect. For example, polycarbonate tableware can be washed over
1000 times in a dish washing machine with no adverse effects being observed.
The table that appears on the following pages lists the resistance of polycarbonate sheet to a number of commonly encountered
chemicals and other corrosive media at room temperature. (Information on chemical resistance at higher temperatures will be supplied
upon request). Where the chemical resistance varies with concentration, the results of tests at different concentrations is presented.
The information on chemical resistance is based on our research and experience. (Note that information on compatible adhesives
and sealants can be found in a separate leaflet which will be supplied upon request) It serves as a basis for recommendation. PALRAM
Industries does not guarantee chemical resistance unless specific separate documentation is supplied.
For chemicals and corrosive media not indicated in the list, please contact your PALRAM representative. He will place you in contact
with the PALRAM R&D & Technology Department.
The table on the following pages uses the following key:
R - Resistant
LR - Limited Resistance (gradual attack over time may occur)
N - Not Resistant (rapid attack or attack over short time period will occur)
Chemical Resistance of PALSUN® Sheets at Room Temperature
The chemical resistance of PALSUN & PALTUF sheets, specified in the following pages, has been demonstrated in actual installations
and/or laboratory tests. The information in the table is based on our research and experience. It should be considered solely as a basis
for recommendation, but not as a guarantee, unless specifically stated in separate documentation supplied by PALRAM Industries.