Commingled yarns – Processing aspects and tailored surfaces of polypropylene/glass composites

Simultaneous spinning of commingled yarns and their investigation in terms of distribution homogeneity, thermal shrinkage, and cross section geometry is described in comparison with those intermingled by air jet texturing. Due to fibre damage avoided in the simultaneous processing and improved distribution homogeneity both hybrid yarn tensile strengths and transverse mechanical properties of unidirectional composites were improved. Nanostructured interfaces introduced by smallest amounts of carbon nanotubes in sizings enable to achieve multifunctional effects such as improved tensile strength of glass fibres, modified morphology of interphases, and new fracture mechanisms.