The aim of this study was to assess the technical feasibility of using industrial waste composed of phenolic resin, lignocellulose, calcium carbonate, talc, mica and carbon black as filler for polypropylene (PP). Composites of PP with 10, 15 and 20 wt% of the waste were processed in a twin-screw extruder followed by injection molding. Molded composites were characterized by scanning electron microscopy (SEM), thermal analyses (DSC and TGA), mechanical tests (tensile, flexural and impact) and thermo-mechanical test (HDT). The composites showed residue particles with sizes less than 500 µm dispersed in the PP matrix. The residue particles acted as nucleating agents for PP crystallization. The composites showed greater thermal degradation resistance as compared to PP. The composites showed a balance of stiffness and mechanical strength with increase of the flexural module and decrease of the tensile strength. The notched impact strength was not altered and the heat distortion temperature (HDT) of the composites was increased as compared to PP. The performance of the composites developed here showed that the industrial waste based on phenolic resin can be used as functional filler for PP. Furthermore, these composites are an alternative for the recycling of the phenolic resin industrial waste.
Polypropylene composites; phenolic resin; recycling
