Curing, mechanical, thermomechanical and rheological properties of new poly(1-hexene-co-hexadiene) rubber

Polyolefin elastomers (POEs), a new family of synthetic commercialized polymers, can be used as an alternative for lots of common elastomers such as ethylene propylene rubbers (EPR or EPDM), poly (ethylene-co- vinyl acetate) (EVA) and poly (styrene-co-butadiene) (SBR). In this research, 1-hexene/1,5-hexadiene copolymer (COPOLY), as a newfound POE was cured with different weight fractions of dicumyl peroxide (DCP) as a curing agent. Curing behavior and ultimate properties of COPOLY were compared with EPDM as a nearby practical and commercial rubber. Mooney viscosity results showed that; by increasing weight fraction of curing agent, scorch times decreased, and the scorch time of COPOLY was lower than EPDM. Tensile measurements showed that COPOLY has comparable Young's modulus with it in EPDM sample (16.11 and 16.51 MPa, respectively). DMTA analysis confirmed more toughness and elastomeric properties of COPOLY in comparison to EPDM rubber. Melt viscosity analysis of the samples exhibited that synthesized rubber has lower melt viscosity than EPDM at all frequency ranges, and also EPDM showed slightly higher elastic modulus in comparison to COPOLY (0.89 and 0.82 GPa, respectively). Fatigue test acknowledged excellent behavior of COPOLY with 45,600 cycles till to failure. The synthesized COPOLY showed significantly higher ozone resistance (142 toward 105 h) and lower abrasion weight loss (11.34 toward 14.28%) than commercial EPDM. Altogether, our obtained results suggest new highly efficient rubber that in all studied aspects has higher capability than EPDM and can be considered as a high performance rubber in industrial applications.