Synthesis and characterization of free radical cured Bis‐methacryloxy bisphenol‐A epoxy networks

Abstract Synthesis and free‐radical curing reaction of the bisglycidylmethacrylate of bisphenol‐A (Bis‐GMA) were investigated. Bis‐GMA resin was synthesized by reacting Epon 825 with methacrylie acid, followed by characterization using IR and NMR spectroscopy. Various modifiers having reactive double bonds were co‐cured with the methacryloxy resins using a free‐radical initiator. The networks obtained were compared with a cycloaliphatic amine‐cured epoxy network. Thermal characterization shows that methacryloxy‐cured systems are more resistant to mechanical penetration and have higher glass‐transition temperatures and better stability with regard to thermal decomposition as compared with the conventional diamine‐cured epoxy networks. Dynamic mechanical experiments and stress‐strain tests also indicate that Bis‐GMA based networks have higher tensile moduli and lower elongation at break. Using different modifiers such as 2‐ethylhexyl acrylate, the tensile and impact properties of the networks can be improved.