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Leicestershire LEI 1 3TU, United Kingdom J. L. CRUZ MACHIN Escuela Militar de lngenieros Calz. Mtkico-Tacuba, Mkxico, D. F.Leather-like composites were prepared by addition of chemically modified short leather fibers (SLF) into a plasticized polyvinyl chloride (pWC) matrix. The fibers were subjected to chemical modification by emulsion polymerization to achieve good interfacial adhesion between SLF and the pWC matrix. The SLF with chemical modification were obtained from three different reaction conditions where these SLF have different percentages of grafted and deposited PMMA polymer onto the fiber surface. The incorporation of the SLF into the thermoplastic matrix was carried out using a torque-rheometer and the composites obtained were molded by compression. Tensile and tear mechanical tests were performed on composite samples, and the morphology of the fractured surfaces was analyzed using scanning electron microscopy (SEM). The results show that the incorporation by grafting of polymethyl metacrylate (PMMA) onto the fibers produced a significant improvement of their interfacial adhesion to pWC, promoting the compatibilization between the fiber surface and matrix. The findings are discussed and interpreted in terms of enhanced adhesion at phase boundaries. Overall, the results confirm that it is possible to produce modified leather composites based on a pPVC matrix, which exhibit relatively high tensile strength, tear resistance and flexibility. These composites are very suitable candidate materials for applications in the footwear industry.

In this work we investigated the application of a novel high performance polymer, polybenzoxazine, as a polymeric matrix in Fiber Metal Laminates (FML). This polymer, when applied on the development of FMLs, generated higher mechanical properties in comparison to fiber metal laminates obtained with epoxy. To investigate the mechanical performance of the polybenzoxazine matrix in FMLs, a mechanical behavior comparison was carried out among epoxy matrix laminates - glass fiber reinforced aluminum laminate (GLARE) and carbon fiber reinforced aluminum laminate (CARALL) - and FML constructed with aluminum and carbon fiber reinforced polybenzoxazine. The mechanical properties were characterized by drop weight impact and flexural methods, and the polybenzoxazine curing behavior through differential scanning calorimetry (DSC). Polybenzoxazine FML generated increasing of: 18% of maximum load, 11% of maximum elongation under flexure and 7.5% of impact energy absorption compared to other fiber metal laminates.