Curing kinetics and mechanism of TDE-85/MeTHPA epoxy resin modified by polyurethane

The TDE-85/MeTHPA epoxy resin modified by polyurethane was prepared with polyurethane prepolymer (PUP, formulated by PPG and TDI), chain-extended reagent(1,4-BDO) and crosslink agent (TMP). The curing reaction mechanism and kinetics characters of the modified resin were discussed by DSC and infrared spectrum analysis. The investigation on curing reaction mechanism indicates that polymer networkⅠwas obtained by the curing reaction between TDE-85 and MeTHPA, and polymer network Ⅱ was obtained by the chain-extended and crosslinking reaction of 1,4-BDO, TMP, and PUP, meanwhile, the graft chemical bond is formed between polymer networkⅠ and polymer network Ⅱ. The investigation on kinetics shows that the apparent activation energy of curing reaction decreased obviously with PU addition, and