Epoxy resin‐based biomass composites based on modified corn stalks: Preparation, properties, and toughening mechanism

Abstract In this study, a series of sustainable eco‐friendly epoxy resin (EP)‐based biomass composites (DSA‐CS/EP) were prepared using bisphenol A EP as matrix, 2‐methylimidazole as curing agent, and corn stalk (CS) esterified with dodecene succinic anhydride (DSA) as filler. The static contact angle test results showed that the hydrophobicity of CS after esterification with DSA (DSA‐CS) was enhanced, which results in the compatibility of DSA‐CS with EP matrix was improved. And then, the DSA‐CSs were dispersed homogeneously in the matrix without agglomerating. The morphology and properties of the biomass composites were studied and analyzed in order to elucidate the toughening mechanism of CS and DSA‐CS. When the content of DSA‐CS is 15 wt%, the tensile strength and impact strength of DSA‐CS/EP reached a maximum value of 30.39 MPa and 3.34 KJ/m², which were increased by 128.49% and 81.52% compared with pure EP. Finally, it is deduced that the possible toughening mechanism is that DSA‐CS can not only share part of the external stress but also a mutual solute region is formed between DSA‐CS and EP matrix. Highlights Corn stalks esterified by DSA were used as reinforcement filler for epoxy resin. The cellulose in CS was mainly esterified. The tensile and impact strength of DSA‐CS 15/EP reached a maximum value. A mutual solute region is formed between filler and matrix.