Moulded articles prodn. e.g. sheets - by granulating waste materials contg. polyester fibres or glass and three=stage pressing

摘要

The prepn. of moulded articles comprises granulating waste materials, mixing with an adhesive and pressing at 150-200 deg.C. The mixt is compressed at 2 bar before pressing, then pressed at 5-10 bar, followed by cooling and calibration at 2 bar. The three pressing processes occur one after the other in three presses. The waste material partly comprises fibre of polyester or glass. The amt. of adhesive is 5-10 wt.%. The adhesive is liq. and comprises melamine-urea-formaldehyde (MUF) mixed condensate or diphenylmethan-diisocyanate (DMDI). Alternatively, the adhesive is in powder form and is polyvinyl butyral, modified terpene phenol resin, epoxy resin or copolymer powder of vinyl acetate ethylene and acrylic acid deriv. USE/ADVANTAGE - Used for making sheets (claimed) at relatively low pressure and with relatively narrow tolerances.