Properties of polyamide epichlorohydrin resin‐modified wood fibers/soybean straw powder copolymerization enhanced soy protein biomass composites

Abstract The biomass composites were prepared by hot molding with a pressure of 10 MPa, a temperature of 125 °C, a time of 15 minutes using soybean straw powder, poplar wood fibers, and soy protein as raw materials. The effects of different straw species, the ratio of soybean straw powder to poplar wood fibers, the particle size of soybean straw powder, and the theoretical density on the performance of biomass composites were investigated. The experimental results show that under the condition that the ratio of soybean straw powder and poplar wood fibers is 1 : 1, 20 mesh to 40 mesh soybean straw powder and 20 mesh to 60 mesh wood fibers are selected to copolymerize and strengthen the soy protein biomass composites when the theoretical density is 0.80 g/cm 3 , the actual density of the biomass composites is 0.90 g/cm 3 , the tensile strength was up to 22.04 MPa, and the bending strength was up to 44.92 MPa. Biomass composites have good water resistance while obtaining excellent mechanical properties. The above figures not only meet the relevant technical requirements of automotive interior parts but also enable the lightweight design of automobiles and the sustainable development concept of green, low carbon, and environmental protection.