Effects of a novel acrylic-based compatibilizer on the mechanical properties, contact angle, water absorption, density and processibility of polyvinyl chloride/wood flour composite

Three terpolymers (P(MAA-BA-MMA)) of methyl acrylate, butyl acrylate, and methyl methacrylate, with different inherent viscosity and carboxyl values were used as compatibilizer for polyvinyl chloride/wood flour composite. The effects of P(MAA-BA-MMA) on improving compatibility between polyvinyl chloride and wood flour and the composite's mechanical properties were studied. It is found that the P(MAA-BA-MMA) with inherent viscosity of 33.87 mL/g and carboxyl value of 3.93 mmol/g can the most greatly improve the mechanical properties of composites. The effects of this terpolymers' content on the mechanical properties, density, water absorption, and processing properties of composite were investigated in detail. The results show that the P(MAA-BA-MMA) can enhance mechanical properties and increase density, decrease water absorption, and improve processing properties of composite, and also reveal a relationship between the trend of P(MAA-BA-MMA)'s influence on tensile strength and that of its influence on density and water absorption. When P(MAA-BA-MMA) is at the optimum loading, the tensile strength and density of the composite are the largest, meanwhile its water absorption is the smallest. This relationship provides a shortcut for optimizing the formula of polyvinyl chloride/wood flour composite effectively. Scanning electron microscope results show that the interface between wood flour and polyvinyl chloride in the polyvinyl chloride/wood flour composite is blurred and combined well after wood flour is treated with P(MAA-BA-MMA).