2023 Volume 44 Issue 5 Pages 232-242
Thermosetting reaction of epoxy resin with ε-caprolactam (ε-CL) and lactide (LAC) proceeded above 170°C in the presence of DBU, yielding the cured materials quantitatively. As a model reaction of this thermosetting reaction, the reaction behavior of ring-opening copolymerization of glycidyl phenyl ether (GPE) with ε-CL and LAC was investigated using the Fineman-Ross method and the Kelen-Tüdös method. In the case of GPE and ε-CL, the monomer reactivity ratio r1 of ε-CL and r2 of GPE were 0.58 and 5.52, respectively. This indicated that the copolymer of GPE and ε-CL was a blocktype copolymer. In the case of GPE and LAC, the r1 of ε-CL and r2 of LAC were 0.85 and 1.26, respectively. This indicated that the copolymer of GPE and LAC was a gradient type copolymer. When the thermosetting reaction of epoxy resins was perfomed by adding ε-CL and LAC, the thermal stability of the cured material could be improved.
