Compression in the processing of polymer composites 1. A mechanical and microstructural study for different glass fabrics and resins

This paper focuses on the compression of fibre reinforcements during the pr ocessing of polymer composites, covering a range of fabrics, namely a plain weave, a twill, a satin and a non-crimped, stitch-bonded fabric. The compr ession of assemblies of fabrics has been studied in both dry and wet states where, in the latter case, the fabrics were impregnated with three alterna tive resins: a non-Newtonian polyester of relatively high viscosity, a non- Newtonian polyester of relatively low viscosity, and a Newtonian epoxy of e qually low viscosity. Investigations of mechanical behaviour included the i nfluence of compression speed, type of fabric and viscosity and type of res in. Microstructural studies of laminates produced under different degrees o f maximum compression elucidated further the results of mechanical compress ion and provided data of average area porosity (resin-rich areas), area por e structure, average area voidage and voids for the different types of fabr ics. (C) 1999 Elsevier Science Ltd. All rights reserved.