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Acrylic (PMMA) Acrylic (PMMA) tolerates weak acids and bases but will not tolerate strong ones nor solvents or acetones. Polymethyl-methacrylate (PMMA), obtained by polymerization of methyl methacrylate (MMA).3 PC made with this acrylic polymer as a binder is a versatile material, has excellent weathering resistance, good waterproofing properties, good chemical resistance, and relatively low setting shrinkage (0.01 to 0.1%); its coefficient of thermal expansion is equivalent to that of Portland cement concrete. The low flash point (11°C) of the MMA monomer is a disadvantage, however as it constitutes a safety problem. PMMA is resistant to aliphatic hydrocarbons, non-polar solvents, aqueous alkalis, and aqueous acids. Aromatic hydrocarbons, chlorinated hydrocarbons, esters, ketones, and other polar solvents attack PMMA, causing it to dissolve or swell. It resists attack by aqueous salt solutions, alkalis and mineral acids.
Approximate Word count = 530
Approximate Pages = 2.1
(250 words per page double spaced)
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