Highly efficient preparation of hyperbranched epoxy resins by UV-initiated thiol-ene click reaction

摘要: Hyperbranched epoxy resins (HEPs) attract an increasingly interest due to their remarkably reinforcing and toughening properties on thermoset. A major challenge for HEPs is the serious environmental pollution resulted from large amount of organic solvents used during tedious synthetic procedure. Another low yield content HEPs, resulting in crosslinking density impairing mechanical strength compatibility with matrix. Here we report a fast environmentally friendly approach addressing these challenges using UV-initiated thiol-ene click reaction. The new synthesis process has been prepare not only hyperbranched epoxides high content, also many kinds glycidyl ether (mono-epoxide, di-epoxides, tri-epoxides) based thiols precursors allylglycidyl ether. Their chemical structures molecular weights were characterized by FT-IR, 1H NMR, electrospray ionization mass spectrometry (ESI–MS) GPC spectra. All reactions took 5–10 min UV radiation at room temperature show very yields between 98.1 99.8%, equivalent weight all close its theoretical value. This may open avenue design as well common resins.