WITHDRAWN: An efficient way for the synthesis of epoxy resin polymers with thermoreversible cross-linking

Abstract

Abstract This work demonstrated an efficient way for the synthesis of thermoreversible cross-linked epoxy resin based on Diels-Alder reaction (DAER) via two steps: a side-chain pendant furan-functionalized liner epoxy resin (LER) was designed and synthesized in the first step; a cross-linked network was constructed via DA reaction between the bismaleimide (BMI) and the pendant furan functional groups in the side chain of the LER in the second step. The cross-linking density could be adjusted by changing the mole ratio of maleic imide in BMI to furan groups in LER. The DAERs could perform de-crosslinking above 100°C and reform the network below 60°C. The results of the tensile experiment showed that the mechanical properties of the DAERs can be compared with the traditional aromatic amine cured epoxy resin. The thermostability of all the cross-linked DAERs were improved significantly compared to the DAER0, especially DAER100 with about 40°C higher transition temperature, which indicated that DA cross-linking was an effective way to improve the heat resistance of the polymer material.