High-performance thermosets with heat resistant properties derived from methacrylated isosorbide and epoxy-based vinyl ester

Styrene (ST) is a common volatile petroleum-based diluent in epoxy-based vinyl ester (VE) resin system. In recent years, a number of renewable molecules, such as eugenol, have been methacrylated and products behaved lower volatility property than ST. However, these renewable resin systems exhibited decreased thermal performance, especially glass transition temperature (Tg). Therefore, these resin systems cannot be used in hash environment. In our work, we used isosorbide to react with methacrylic anhydride and the synthesized monomer was mixed with VE resin to produce new bio-based resin system-MIVE. Volatility, viscosity and thermomechanical properties of MIVE and VE/ST resin were examined. The results indicated that MIVE had excellent low volatility property and Tg of MIVE can achieve 210 oC. Furthermore, we discussed the approach to improve heat resistant property of resin system. Acrylates with vinyl groups, including hydroxyethyl methacrylate (HEMA), pentaerythritol triacrylate (PETA) and dipentaerythritol pentaacrylate (DPHA), was grafted to MIVE respectively. Dynamic thermomechanical analysis (DMA), heat distortion temperature (HDT) and thermogravimetric (TGA) tests were used to measure thermal performance of grafted resin systems. The results showed Tg of grafted MIVE ranged from 210 to 240 oC, HDT ranged from 160 to 230 oC and initial decomposition temperature (IDT) (5% weight loss) were over 400 oC. Overall, studies showed that grafting acrylates with vinyl groups to VE was an effective way to improve the heat resistant properties of bio-based resin systems.