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Bisphenol-C epoxy cinnamate (ECC) resin was synthesized by reacting 8.09 g epoxy resin of bisphenol-C, and 3.70 g cinnamic acid using 25 ml 1,4-dioxane as a solvent, and 1 ml triethylamine as a catalyst at reflux temperature for 1–6 h. Solid epoxy cinnamate is found to have excellent solubility in common organic solvents, 10.4–4.1 mg KOHg−1 acid values, and 303.0–426.0 mg KOH g−1 hydroxyl values. FTIR and 1HNMR spectral data supported the structure of ECC. Thermal polymerization of ECC followed by decomposition is supported by DSC exothermic (142.9°°C) and broad endothermic (300°°C) transitions. ECC followed three steps of degradation kinetics. The first step followed first-order (1.13) degradation kinetics, while the second (2.40) and the third (0.58) steps followed fractional-order degradation kinetics. The energy of activation for the second and third steps is more than 3 times that of the first step. The entropy change (ΔS*) for the first (− 176.3JK−1 mol−1) and third (− 84 JK−1 mol−1) steps are found large and negative, while it is positive for the second step (9.4 JK−1 mol−1). Jute-, Glass- and Jute-biomass-ECCS composites showed moderate to fairly good tensile strength, flexural strength, electric strength, and fairly good volume resistivity. J-ECCS and G-ECCS composites showed high water absorption tendency and excellent hydrolytic stability against water, 10% aq. HCl and 10% aq. NaCl and even in boiling water. The composites may be useful during natural calamities and under diverse environmental conditions. [ABSTRACT FROM AUTHOR]

Bisphenol-C epoxy crotonate resin was synthesized by reacting 8.09g epoxy resin of bisphenol-C, and 2.15g crotonic acid using 25 mL 1,4-dioxane as a solvent, and 1 mL triethylamine as a catalyst at reflux temperature for 1-6 h. Solid epoxy crotonate (ECCR) is highly soluble in common organic solvents. ECCR was characterized by its acid (24.5-1.5 mg KOH/g) and hydroxyl (504.5-678.4 mg KOH/g) values. The structure of ECCR is supported by FTIR and 1HNMR spectroscopic methods. A DSC endothermic transition at 229oC indicated melting followed by thermal polymerization of ECCR. ECCR is thermally stable up to 320oC and follows three-step degradation kinetics. The first step followed first-order degradation kinetics, while the second and third steps followed one-half-order degradation kinetics. High values of kinetic parameters suggested the rigid nature of the crosslinked resin. Jute-, Glass- and Jute-natural fiber-ECCR composites showed moderate tensile strength, flexural strength, electric strength, and volume resistivity due to the rigid nature and poor interfacial adhesion of the composites. J-ECCR and G-ECCR composites showed high water absorption tendency and excellent hydrolytic stability against water, 10% aq. HCl and 10% aq. NaCl and even in boiling water. Mechanical and electrical properties and water absorption tendency of the composites indicated their usefulness as low load-bearing housing and insulating materials. They can also be utilized in harsh environmental conditions. [ABSTRACT FROM AUTHOR]