Thermoplastic polyester with improved dimensional stability - comprises polybutylene terephthalate, and clay, metasilicate, polyester, polycarbonate and novaculite-modifier

摘要

A thermoplastic compsn (I) comprises (a) a mixt. of poly-(1,4-butylene terephthalate) (PBT) and poly(ethylene terephthalate) and (b) =60 pts. wt. of a modifier per 100 pts (I). The modifier comprises >=1 of (i) (amino)silane-treated clay, (ii) acicular Ca metasilicate, (iii) segmented copolyester and aromatic polycarbonate and (iv)novaculite. Also claimed is a compsn. comprising PBT and modifier of aminosilane-treated clay and a segmented copolyester. Compsns. (I) are useful for moulding e.g. injection compression and transfer and have low warp after moulding and excellent impact strength.