Ductile woven silk fibre thermoplastic composites with quasi-isotropic strength

Abstract

The combination of ductile Bombyx Mori silk fibre with ductile thermoplastic matrices, combined with the use of a woven fibre architecture, leads to ductile composites with quasi-isotropic strength. Bending and tensile properties were determined for (0,90)_s silk twill weave composites, with different thermoplastic polymers and as reference epoxy resin. Thermoplastic (0,90)_s woven silk fibre composites are isotropic in strength (about 135 MPa at 50% fibre volume fraction) due to the high elongation to failure of both the silk fibre and the thermoplastic matrix allowing extensive shearing of the silk fabric when loaded in the 45° direction. A good quality interface has a clear positive influence on the mechanical properties especially on the bending yield strength.