Direct usage of products of poly(ethylene terephthalate) glycolysis for manufacturing of rice husk/unsaturated polyester composite

Unsaturated polyester resin, synthesized from glycolyzed product of poly (ethylene terephthalate) (PET),waste was combined with rice husks to form rice husk (RH)/polyester composites. PET from post-consumer soft drink bottles was recycled through glycolysis, followed by polyesterified with maleic anhydride and then cross-linked with styrene to produce a formulation for the resin. Characterizations of the synthesized resin were performed by hydroxyl and acid values determinations and Fourier transform infra red (FTIR) technique. The FTIR result for the prepared resin showed that cross-linking between polyester chain and styrene as cross-linkable monomer occurred at their unsaturated active sites. The effects of filler loading and surface modification of rice husks on the mechanical properties and water absorption of the composites were also investigated. It has been observed that the increasing filler loading resulted in reduction of tensile strength, elongation-at-break and impact energy but increased tensile modulus, hardness and water absorption. At similar filler loading, alkalized filler composite has higher mechanical properties. This observation was well supported by the SEM investigations of the fracture surfaces.