Low Gloss Additives

Thermoplastics having a low gloss finish are useful in the manufacture of articles and components for a wide range of applications, 

Low gloss additives have been described, such as epoxy resins. In addition, SAN copolymers are specifically useful. Suitable SAN copolymers have 75% styrene content. The low gloss additive gel is melt blended, with another resin, e.g., PC. 

As usual, certain additives can be added to the composition. Among others, the use of an anti-drip agent has been proposed, namely poly(tetrafluoroethylene) (PTFE)). The anti-drip agent may be encapsulated by a rigid copolymer, for example, SAN, which is known as teflon encapsualed in SAN (TSAN) (29). 

Encapsulated fluoropolymers can be made by polymerizing the encapsulating polymer in the presence of the fluoropolymer, for example in an aqueous dispersion. TSAN may provide significant advantages over PTFE, in that TSAN may be more readily dispersed in the composition. A suitable TSAN may is composed from 50% PTFE and 50% SAN (29). 

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