Multiscale morphological analysis of commingled PP/unidirectional glass fiber composites: Experiment and theory

Quantitative 2D image processing has been performed to assess the morphology of commingled polypropylene composites reinforced by a range of glass fiber contents. Quantitative morphological probes, derived from both local and global analyses, point out the heterogeneous dispersion of unidirectional fibers within the polymer matrix, i.e., the presence of aggregates. It is found that more than 86% of fibers are packed into aggregates at a maximum packing fraction of 0.84 whatever the filler content. Moreover, accounting for these morphological characteristics and based on the percolation concept, prediction of the morphology behavior of such composites is proposed. A good agreement between theory and experiment is found.