摘要 |
<p>The present invention provides a non-burning, nondripping polyester blend composition in which transesterification is suppressed, as indicated by, e.g., improved heat deflection temperature. The composition comprises (a) approximately 35 to 85 percent by weight of a blend of polyethylene terephthalate and polybutylene terephthalate wherein the polyethylene terephthalate comprises approximately 10 to 25 percent by weight of the blend; (b) approximately 5 to 60 percent by weight of a reinforcing agent; (c) approximately 4 to 15 percent by weight of at least one halogen-containing organic flame retardant compound; and (d) approximately 2 to 10 percent by weight of the amorphous non-abrasive reaction product of antimony trioxide, or a compound of antimony which generates antimony trioxide, and a substrate comprising a hydrous compound of silicon in a weight ratio within the range of approximately 1:1 to 1:4, on an antimony trioxide:substrate basis. The composition may further comprise approximately 0.1 to 8 percent by weight of a thermoplastic phenoxy resin and/or approximately 0.5 to 2.5 percent by weight of a polytetrafluoroethylene resin. The amorphous non-abrasive reaction product is preferably the reaction product of antimony trioxide and talc, preferably in a 25:75 or 45:55 weight ratio. A process for suppressing transesterification in glass reinforced, non-burning, non-dripping polyester blend compositions is also disclosed. The novel blend, with suppressed transesterification and the associated reduction in the lowering of heat deflection temperature, is more suitable for use in the manufacture of products with improved fine characteristics.</p> |