Hot-pressure forming process of PVC/geopolymer composite materials

This paper describes a method to fabricate geopolymer composite materials with high toughness at low cost, which were fabricated by plasticizing polyvinyl chloride (PVC) and metakaolin-based geopolymers using a hot-pressure forming process. The experimental results showed that the PVC/geopolymer composite materials fabricated by the hot-pressure process possess flexural strengths higher than the pure PVC materials (59 MPa), up to a maximum geopolymer content of 50 mass%; however, a bending displacement exists under a load that decreases with increasing geopolymer content. Although the addition of a geopolymer can increase a lower softening temperature and rigidity compared to PVC composites, it has a decreased ductility. When the geopolymer content in the composite exceeds 50 mass%, the flexural strength was lower than the pure PVC but significantly higher than that of the pure geopolymer (15 MPa). Hence, by employing additional amounts of geopolymer and partly substituting PVC resin in the composite, the high-temperature stability is improved, and the fabrication costs for industrial applications are significantly reduced.