Synthesis and Application of Polyepoxide Cardanol Glycidyl Ether as Biobased Polyepoxide Reactive Diluent for Epoxy Resin

Polyepoxide cardanol glycidyl ether (PECGE), a novel cardanol derivative, was synthesized and used as reactive diluent for petroleum-based epoxy resin in this work. The synthetic condition was first optimized, and the resultant PECGE diluent was characterized using Fourier transform infrared spectroscopy, 1H NMR, and 13C NMR. The influence of addition of this diluent on the viscosity of the diluent epoxy resin was also studied. Mechanical and heat-resistant properties of the cured epoxy resin containing PECGE were especially evaluated. By the addition of PECGE into the petroleum-based epoxy resin, the viscosity of the obtained epoxy resin was reduced. The tensile strength, elongation at break, and heat-resistant property of the obtained resin were all improved, while the flexural and compressive strengths of the resin only slightly decreased, implying the potential of PECGE as a very promising biobased reactive diluent for epoxy resin.