Modification of Unsaturated Polyester Resin by Eleostearic Acid

Abstract

General type unsaturated polyester resin (UPR) is largely used in coating industry as a film-forming resin. However, the general type UPR has some disadvantages which limit its applications such as poor water resistance, heat resistance and mechanical properties. Modifications, especially structural modifications are needed to improve UPR’s comprehensive performance. Here, eleostearic acid (EA), a derivative from a Chinese renewable vegetable oil, Tung oil, has been employed to modify UPR’s structure. Influences of EA’s dosage in EAmodified- UPR on water absorption and tensile strength, scanning electron microscope morphology and thermal stability were investigated. Experimental results show that the water resistance and tensile strength of UPR have been improved a lot and the heat resistance of UPR also has a certain degree of improvement after EA-modification. When the mass dosage of EA is 9% of UPR, the water absorption of UPR are decreased by 12.3% while the tensile strength is increased by 35.5% after modification and the final thermal decomposition temperature are increased from 440 oC to 458.7 oC.