文摘
A highly functional unsaturated ester macromonomer was synthesized from soybean oil (SBO), and its chemical structure was confirmed by FT-IR, 1H NMR, 13C NMR, and gel permeation chromatography. The monomer was prepared through modifying epoxidized soybean oil (ESO) first with a synthesized precursor, hydroxyethyl acrylated maleate (HEAMA), and then employing maleic anhydride (MA) to modify the produced ESO-HEAMA. The obtained SBO-based monomer (ESO-HEAMA-MA) possessed a C═C bond functionality of 6.75–8.15 per ESO. Effects of styrene concentration, feed ratio, and initiator concentration on the dynamic mechanical properties of the cured bioresins were investigated carefully. When the monomer with the highest C═C bond functionality was used, the cured resins with 20–60 wt % styrene demonstrated cross-link densities of 5.07–9.52 (103 mol)/m3, storage moduli at 25 °C of 1.32–2.16 GPa, glass transition temperatures of 69.9–114.1 °C, and tensile strengths and moduli of 19.7–33.1 MPa and 1.17–2.11 GPa, respectively. Microstructural morphologies of tensile-fractured surfaces of the cured resins were studied by scanning electron microscopy. Finally, curing behaviors of the resultant resin was studied by differential scanning calorimetry. The developed eco-friendly biomaterials have potential applications in the industry of unsaturated polyester resins.