Useful polymers can be obtained from a variety of acrylic monomers, such as acrylic and meth-acrylic acids, their salts, esters, and amides, and the corresponding nitriles. Polymethyl meth-acrylate, polyethyl acrylate, and a few other derivatives are the most widely used.
Polymethyl methacrylate is a hard, transparent polymer with high optical clarity, high refractive index, and good resistance to the effects of light and aging. It and its copolymers are useful for lenses, signs, indirect lighting fixtures, transparent domes and skylights, dentures, and protective coatings.
Solutions of polymethyl methacrylate and its copolymers are useful as lacquers. Aqueous latexes formed by the emulsion polymerization of methyl methacrylate with other monomers are useful as water-based paints and in the treating of textiles and leather.
Polyethyl acrylate is a tough, somewhat rubbery product. The monomer is used mainly as a plasticizing or softening component of copolymers. Ethyl acrylate is usually produced by the dehydration and ethanolysis of ethylene cyanohydrin.
Modified acrylic resins with high impact strengths can be prepared. Blends or "alloys" with polyvinyl chloride are used for thermo-forming impact-resistant sheets.
Methyl methacrylate is of interest as a poly-merizable binder for sand or other aggregates, and as a polymerizable impregnant for concrete: usually a cross-linking acrylic monomer is also incorporated.
Polymers of methyl acrylate or acrylamide are water-soluble and useful for sizes and finishes. Addition of polylauryl methacrylate to petroleum lubricating oil improves the flowing properties of the oil at low temperatures and the resistance to thinning at high temperatures.
