Novel bio-based IPNs obtained by simultaneous thermal polymerization of flexible methacrylate network based on a vegetable oil and a rigid epoxy

A series of novel vegetable oil-based interpenetrating polymer networks (IPNs) have been successfully prepared: on one hand, methacrylated camelina oil (MCO) and a polyethyleneglycol dimethacrylate (PEG, MW 750g/mol) and on the other hand, diglycidylether of bisphenol A (DER), in various blend ratios (75/25, 50/50, and 25/75wt). Hence the appealing innovative direction of the current work was to build oil-based poly(methacrylate) network using PEG macromonomer which is able to modulate adequately the crosslinking degree of the oil-based network. These innovative combinations of cross-linkable resins in terms of flexible methacrylate network based on camelina oil (CO) and PEG and a rigid epoxy (DER) were simultaneously polymerized using two independent non-interfering curing reactions: free-radical process for MCO and anionic polymerization of epoxy resin in the presence of a tertiary amine. The effect of the IPNs composition compositional characteristics on the reactivity of methacrylate or epoxy groups was studied using differential scanning calorimetry. The influence of the MCO-PEG bio-based polymer on the system properties was evaluated after curing by dynamic mechanical and thermogravimetric analyses. In addition mechanical and morphological studies were also carried out. The results suggested that blending of MCO and DER gave synergistic effects on the overall properties of the developed oil-based IPNs and a dependence on the methacrylate/epoxy ratio was clearly noticed. Copyright (c) 2014 John Wiley & Sons, Ltd.