Dispersion of soybean flour in dicyclopentadiene resin for thermoset composite using the ultrasonic‐assisted method

Abstract Thermosetting composites based on dicyclopentadiene (DCPD) in the presence of Grubbs' catalyst and soybean flour were prepared by ring‐opening metathesis polymerization. Soybean flour/DCPD suspensions were sonicated to enhance the dispersion degree before adding catalyst. The curing extent, thermal‐mechanical properties, morphology and thermal stability of the cured soybean flour/DCPD composites were systematically investigated using Soxhlet extraction, DSC, DMA, TMA, tensile test, SEM, and TGA. The results showed that the tensile strength of the soybean flour/DCPD composites increased from 60.7 MPa to 75.8 MPa with the increase of soybean flour loading from 0% to 25%, and the T_g obtained from DMA also showed an increasing trend from 129.4°C to 155.1°C. Overall, the introduction of soybean flour into DCPD resin improved the thermal‐mechanical properties of the composite and offered decreased cost and enhanced bio‐based content.