Synthesis and characterization of epoxy resin-polydicyclopentadiene interpenetrating polymer networks by UV-initiated simultaneously frontal polymerization

Abstract

By combination of UV curing and frontal polymerization, interpenetrating polymer networks (IPNs) based on diglycidyl ether of bisphenol-A (DGEBA) epoxy resin and polydicyclopentadiene (PDCPD) were prepared by UV-induced simultaneously frontal polymerization in this paper. Compared with the net DGEBA cured polymer, the tensile strength, elongation at break and impact strength of the IPNs were simultaneously improved. The maximum tensile strength and elongation at break of the IPNs reached 100 MPa and 4.64%, respectively, and the maximum impact strength reached 7.34KJ/m² with an improvement of 115.2% over that of the net DGEBA cured polymer. Thermogravimetric analysis (TGA) results revealed that the IPNs could enhance the thermal stability. Data of the differential scanning calorimetry (DSC) and TGA testing shows that the IPN shows a single glass transition temperature (T_g) which is between the T_g of DGEBA and DCPD, indicating homogeneous phase and highly cross-linked IPN formed. Morphologies and molecular structure of the IPNs polymer were observed by scanning electron microscope (SEM) and characterized by Fourier transform infrared spectroscopy (FTIR), respectively, whose results also proved the formation of ideal IPNs structures.