Recycling fibre-contg. uncured thermosetting resin - by extracting with low-boiling solvent, e.g. methanol, sepg. from fibre, opt. concentrating, and using again to impregnate fibre

摘要

A process for recycling residues (I) of fibre sheet (II) impregnated or coated with incompletely cured thermosetting resin, the process involves opt. precrushing (I), extracting with a suitable low-boiling solvent, sepg. the resin soln. from the fibre, possibly concentrating and using again to impregnate (II). Extn. is carried out continuously or discontinuously in a suitable extractor, opt. with intensive stirring and reflux cooling, using acetone, alcohol or methanol as solvent, and the extract is conc. by addn. of fresh resin, the sepd. fibres are dried, crushed and used for the prodn. of moulding materials, friction linings etc. or processed (opt. after drying) as nonwoven sheet prods., esp. paper and millboard stock. USE/ADVANTAGE - The process provides a simple process for recycling uncured resin-impregnated fibre residues, without adversely affecting the properties of the intermediate-stage resin (w.r.t. the properties of the final resin/fibre prods.)