Study on polyblending epoxy resin adhesive with lignin I-curing temperature

As a three-dimensional amorphous biopolymer composed of phenylpropanoid units linked together by ether and carbon–carbon bonds, lignin is considered to be one of the most promising future organic resources not only because it is renewable, but also because it is second only to cellulose in abundance among the naturally occurring polymers. Due to its phenolic ether structure, lignin can be used to blend with other polymers to improve the heat-resistance of the polymers. So, in this study, a type of epoxy resin adhesive polyblended with corn straw enzymatic hydrolyzed lignin was prepared, and the effect of curing temperature on the adhesive joint shear strength of the epoxy resin adhesives under room temperature and high temperature respectively was also studied. The curing degree for the curing reaction of the epoxy resin was examined by FTIR analysis. The apparent activation energy for modified epoxy resin was calculated by DSC analysis. The results showed that the epoxy resin adhesive blended with corn straw enzymatic hydrolyzed lignin exhibited excellent shear strength under room and high temperature. The curing temperature of epoxy resin showed a considerable influence on the performance for the epoxy resin adhesive. The mentioned epoxy resin adhesive can be used to adhere polymer composites in which high temperature shear strength was required.