Neutral comonomers methyl methacrylate

Typically, carboxylate ionomers are prepared by direct copolymerization of acrylic or methacrylic acid with ethylene, styrene or similar comonomers by free radical copolymerization (65). More recently, a number of copolymerizations involving sulfonated monomers have been described. For example, Weiss et al. (66-69) prepared ionomers by a free-radical, emulsion copolymerization of sodium sulfonated styrene with butadiene or styrene. Similarly, Allen et al. (70) copolymerized n-butyl acrylate with salts of sulfonated styrene. The ionomers prepared by this route, however, were reported to be "blocky" with regard to the incorporation of the sulfonated styrene monomer. Salamone et al. (71-76) prepared ionomers based on the copolymerization of a neutral monomer, such as styrene, methyl methacrylate, or n-butyl acrylate, with a cationic-anionic monomer pair, 3-methacrylamidopropyl-trimethylammonium 2-acrylamlde-2-methylpropane sulfonate. 

Methyl methacrylate (MMA) is a monomer or comonomer in many polymers, most notably Plexiglas (R). The conventional process has many drawbacks, including the use of sulfuric acid as a catalyst. Most manufacturers neutralize the sulfuric acid with ammonia, producing byproduct ammonium sulfate which must be sold or disposed of. HCN is also used in the process, requiring the MMA plant to be linked to a source of hazardous HCN. 

In acrylic latices, the hard monomer is methyl methacrylate and the plasticizing monomer an acrylate, such as butyl acrylate or one of the acrylate comonomers mentioned above. Acrylic latices usually contain copolymers of acrylic or methacrylic acid as colloids and thickeners, these being solubilized by neutralization with base. Whatever the type of latex, coalescing solvents are also normally added to improve film formation. These may or may not be water miscible and include alcohols, glycols, ether-alcohols, ether-alcohol esters and even hydrocarbons, all of high boiled point. 

Both acrylic and modacrylic fibres are based on atactic polyacrylonitrile. The generic name acrylic fibre refers to fibres made from linear copolymers that consist of not less than 85 wt % acrylonitrile units. The majority of commercial acrylic fibres contain between 5 and 8% of neutral comonomers, namely vinyl acetate, methyl acrylate or methyl methacrylate. In addition, smaller quantities of various ionic comonomers e,g, sodium styrenesulfonate) are used to provide, together with the ionic end-groups formed from sulfonate and sulfate initiators, the dye sites in the fibres. 

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