Polymerization of Acrylics

Abstract

The significant fiber properties of the acrylics, such as high tenacity, solvent-resistance, heat- resistance, and spinnability from solution, are correlated with chemical structure. Observations on second-order transition temperature, theoretical melting point, heat of fusion, entropy of fusion, and cohesive energy density are made. The effect of molecular weight on general fiber properties is considered. The copolymerization of acrylonitrile with other monomers is treated in some detail, with emphasis on reactivity ratios in copolymerization and relationship to monomer structure. The effect of copolymerization on fiber properties is also discussed. Free radical, carbonium, and carbanionic catalysis in acrylonitrile polymerization are compared with regard to polymerization method and copolymer formation. The role of azo and per sulfate catalysts in aqueous polymerization is discussed. Aqueous, nonaqueous, mass, solution, and solvent-nonsolvent polymerizations of acrylonitrile are treated. Dyeability of acrylonitrile compositions with acid dyes is correlated with basic comonomer structure. The copolymerization characteristics of acrylonitrile with certain basic monomers are discussed with respect to influence of basicity, catalysis, and structure. Alternative means of producing basic acrylic compositions are treated. Aminated methyl vinyl ketone copolymers, allyl glycidyl ether copolymers, and methallyl chloroacetate copolymers are discussed: Some observations are made on future trends in the study of acrylonitrile polymerization. Hydrophilic acrylic compositions and plasticization for spinning purposes are considered.