Preparation and characterization of high damping poly(epichlorohydrin) and poly(epichlorohydrin-co-ethylene oxide-co-allyl glycidyl ether) elastomers: I. Effect of curing system and blending on the damping properties

In this study, the effect of curing system on the rheological, network structure, mechanical and damping properties of poly(epichlorohydrin) (CO) and poly (epichlorohydrin-co-ethylene oxide-co-allyl glycidyl ether) (GECO) elastomers and also blend of CO and GECO were investigated. To identify the curing system's effect on elastomers damping behavior, ethylene thiourea (ETU) and 2,4,6-Trimercapto-s-triazine (TMT) were used as curing agents. To determine the impact of blending on the damping properties of epichlorohydrin-based elastomers, the homopolymer of epichlorohydrin (CO-DP5245) and the terpolymer of epichlorohydrin (GECO-T3108) was mixed in equal proportions. It has been observed that with the use of TMT instead of ETU for both CO and GECO elastomers, the mechanical properties can be significantly increased without changing the damping behavior. CO-DP5245, which has a much higher long chain branching value than GECO-T3108, shows effective damping (tanδ > 0.3) at particularly high temperatures (between −1.7oC to +70oC), while GECO-T3108 has been found to show effective damping at low temperatures (between −41.6oC and − 8.3oC). By blending the homopolymer DP5245 and terpolymer T3108 of epichlorohydrin, it has been proven that elastomers with high damping properties can be easily prepared for moderate temperatures where these elastomers have relatively low damping properties. As a result of these studies, it has been proven that the mechanical, dynamic-mechanical, damping, and energy dissipation properties of ECH-based elastomers can be changed in a controlled manner by changing the type of curing agent by preparing compounds in the presence or absence of resin or by using high damping ECH homo and terpolymer blends.