Unsatd. polyester compsn. bonded directly to metal for vehicle parts - contg. EVA-polyvinyl acetate combination as shrinkage reducer and organic polymer reinforcing fibre(s)

摘要

Reduced shrinkage, fibre-reinforced polyester moulding compsn. is based on an ethylenically unsatd. polyester, an ethylenically unsatd. comonomer and opt. thickeners, radical formers, inhibitors, fillers, flame retardants, lubricants and colourants. Compsn. is characterised by: (i) the shrinkage-reducing thermoplastic polymer is a combination of (a) a sol. and/or swellable EVA-based thermoplastic copolymer with (b) a sol. and/or swellable polyvinyl acetate; and (ii) the reinforcing fibres are of an org. polymer, pref. polyester or polyacrylonitrile. The EVA copolymer component of the shrinkage reducer pref. has a vinyl acetate content of 30-80 wt.%. The reinforcing fibres are esp. polyethylene terephthalate or polyacrylonitrile fibres and are pref. present in an amt. of 0.2-30 (esp. 1-10) wt.% of the total compsn. a filler pref. also being present.