Maleic half-ester copolymer foams prodn - using ammonia (source) - as blowing agent have high heat distortion temp

摘要

Foams are produced by mixing copolymer of maleic acid half-ester and other comonomer(s) with urotropine, NH3 and/or NH4 salt and then heating. These foams can be used for insulating and decorative purposes, as packaging materials, and in combination with other materials, e.g. clay, concrete, (glass) fibres natural or synthetic resins. They have relatively high elasticity and heat distortion temp. >130 degrees C, i.e. much better than thermoplastics like polystyrene and polyethylene. They can be produced with low bulk density and uniform pore structure and are pure white or light coloured.