Published April 1970
The large growth and development of the plasticizer industry began in the 1930s with the commercialization of polyvinyl chloride and with the discovery that hard and brittle vinyl chloride polymers were made soft, flexible, and immensely useful through the incorporation of plasticizers. Because the initial requirements were few--chiefly compatibility and low volatility--the industry, during the 1940s, was inundated with potential and proposed plasticizing materials. Most of these never reached commercialization.
Over the past two decades, the production of plasticizers has grown enormously. The desirable properties and functions of a plasticizer have been much more clearly defined. The performance of plasticizers in relation to their physical properties and molecular structure has been made much more comprehensible and predictable. An increasing number of performance requirements, aided by industrial attrition, has narrowed production to a relatively few large volume groups of structurally similar plasticizers having the optimum combination of various properties for the major applications.
On the periphery of the major, large volume plasticizers is a host of other materials that, by reason of availability or some specific capability, occupy a small portion of plasticizer markets. Included with these are the developing plasticizers that may someday reach major status as well as those with fading potentials. Just outside this grouping, but related to the primary plasticizers, are the less compatible secondary plasticizers or extenders, the high molecular weight modifiers for averaging polymer properties, and the internal plasticizers that are sometimes built into polymer structures. These groups are also well behind the major primary plasticizers in volume of production and economic importance.