Effect of temperature on mechanical properties and creep responses for wood/PVC composites

This work presents the effect of temperature on mechanical properties and tensile creep responses of Wood/PVC (WPVC) composite materials. The materials were produced by an industrial scale twin crew extruder using the weight ratio of wood and PVC compound of 1:1. The tensile, compressive, and flexural properties were determined at various temperatures (25 °C, 40 °C, 50 °C, 60 °C, and 70 °C). The tensile creep responses and creep models at these temperatures were also included in this work. The experimental results indicate that mechanical strength of WPVC composites decreased significantly at temperature higher than 50 °C while the modulus of elasticity was affected significantly at temperature higher than 60 °C. The material properties at large deformation as mechanical strength was found to be more sensitive to the temperature change than the mechanical modulus at small deformation. The empirical equation representing mechanical properties as a function of temperature was also provided together with recommended adjustment factors for the design phase. The creep models combining time-stress dependencies using power form and time-stress-temperature dependencies using Pickel's form were obtained. Close agreement was observed representing adequacy of these models to predict the long-term deformation of the WPVC composites. This provided information would be useful for the design of WPVC composite member in structural and construction applications.