Composite for insole shoe assembly based on polyvinyl acetate and polyester fabric waste from the footwear industry

Abstract This work aimed at studying a composite material for shoe assembly insole using polyester fabric waste (PFW) from the footwear industry. For the preparation of the composites, polyvinyl acetate (PVAc) was employed as the polymeric matrix, with 5%, 10%, 15%, and 20% in weight of PFW in the formulations and compared with a standard formulation without PFW. The samples were characterized via physical–chemical (moisture content, bulk density, and growth/shrinkage) and mechanical (break, tensile and dry, and wet tear) analyses, and also by scanning electron microscopy. The PVAc/PFW 5% and 10% composites showed satisfactory results in all tests performed. They reached 9.99 and 9.09 MPa tensile strength, respectively, twice the minimum acceptable (5 MPa), and 1.13 and 1.07 N/mm dry tear strength, also higher than required (1.0 N/mm). The better results for the samples with less PFW were justified by the lower tendency to produce agglomerates during the molding and compaction production stages. Compared with commercial materials commonly used in shoes, these samples met all specifications and showed the technical feasibility of reusing PFW in assembly insoles.