Clean polycarbonate material for use in hard disk drive and semiconductor applications

摘要

Compositions based on polycarbonate copolymers to provide ultra-clean materials and articles useful in the hard disk drive and semiconductor industries. In one aspect, the compositions include a polycarbonate copolymer based on a sebacic acid, BPA, PCP polyestercarbonate. The compositions may be used with or without other polymers, fillers or additives. The compositions based on this polycarbonate copolymer exhibit ultra clean performance, low organic contamination, low LPC, and low ionic contaminations. Meanwhile, the compositions also exhibit good flow ability, good ductility and good surface quality.

主权项

1. A thermoplastic composition, comprising:
(a) 50 to 95% by weight of at least one polyester-polycarbonate having a weight average molecular weight between 30,000 to 40,000 Daltons as measured by gel permeation chromatography polycarbonate standards and 5.0 mole % to 15.0 mole % sebacic acid and at least one polyester-carbonate having a weight average molecular weight between 15,000 to 25,000 Daltons as measured by gel permeation chromatography using polycarbonate standards and 5.0 mole % to 12.0 mole % sebacic acid; and (b) 5 to 50% by weight of at least one filler selected from glass, ceramic fiber, carbon fiber, a conductive filler, polytetrafluoroethylene, or a combination including at least one of the foregoing fillers; wherein the composition, as compared to a composition comprising a bisphenol A-based polycarbonate having at least one same filler and filler loading, has a melt volume rate as measured according to ASTM-D1238-10 that is at least 20% higher, an impact strength that is at least 20% higher, and a liquid particle count that is at least 20% lower.