Prodn. of composite laminates - by laying together stack of reinforcing fibrous, materials and thermoplastics, enclosing in film tubing, exhausting tubing and hot pressing

摘要

Sheets of composite material are produced by laying up a stack of reinforcing fibre material and thermoplastics and continuously feeding it inside evacuated film tubing in a press. The films used are polymers which are preferably modified in M.W. by the use of copolymers, block polymers, grafted or mixed polymers. The press used is an intermittently closing heated press with one or more daylights, but a double-band type is preferred. The fibrous material used can be fabric, knitwear, braided material etc.. The stack of material is covered with the film in the form of a tube which is fed transversely to the material and has the edges bonded together, whilst its interior is evacuated. The stack preferably has a number of layers of the fibrous and thermoplastic materials respectively. ADVANTAGE - Method is continuous. In particular it overcomes the problems of occluded air and of processing in a vacuum to eliminate such air.