Classes of Emulsion Polymers

Emulsion polymers derived from acrylic monomers are easily the most composi-tionally diverse and versatile family of the commercially important broad classes of emulsion polymers. By acrylic we mean polymers of mcHiomeric alkyl esters of acrylic and methacrylic acid, but also include, usually as lesser components of the polymers, the free acids themselves and derivatives such as their amides, nitriles and aldehydes, as well as amides and esters bearing functional groups on the side chain, such as hydroxyl. 

This article will provide a general overview of the emulsion polymerisation process and explain how the resulting latexes are used in industrial applications. An introduction to the basic concepts of emulsion polymers will be given, followed by a description of the various production processes and characterisation methods. The classes of emulsion polymers will be surveyed, and the commercial technologies and potential future uses discussed. A number of comprehensive texts on emulsion polymers are available for more in-depth study (60, 89, 94,95, 364, a.l-a.ll). 

There are three main classes of emulsion polymers that account for the bulk of the latexes produced today. These are the styrene-butadiene mbbers, polyacrylics and polyvinyl acetate. Most latexes are produced as copolymers within these general classifications, with the copolymer composition depending upon the desired latex properties. There are other latex classes, of lesser commercial importance, being produced, including polyurethanes (52), acrylonitrile-butadiene mbbers (299) and polyvinyl chloride dispersions (409). 

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