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, H-1 NMR, and C-13 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.