EFFECTS OF ADDITIVES FOR THERMOPLASTICS ON PROCESSING AND FINAL PRODUCT PROPERTIES.

The use of additives in polymers dates back to the earliest developments in the industry, when it was far simpler to compound around a problem to change the processing equipment or base polymer structure. Few polymers are useful in their natural form. Compounding additives were used to permit processing or to increase output rate on existing equipment, to enhance or overcome property deficiencies, to reduce cost, or a combination of these factors. In this article additives are classified according to those which overcome product deficiency during processing, those which modify properties or cost and those which satisfy government regulations. Emphasis is placed on the effect additives have on processing (in particular fusion and flow behavior) and properties. While polyvinyl chloride serves as the base polymer for much of this review, in general the conclusions reached apply equally well to other thermoplastic polymers.