Scrutinizing the influence of peroxide crosslinking of dynamically vulcanized EVA/TPU blends with special reference to cable sheathing applications

Abstract

A novel thermoplastic vulcanizate (TPV) based on the blends of ethylene vinyl acetate/thermoplastic polyurethane (EVA/ TPU) at various blend ratios has been developed via dynamic vulcanization at 180 8C using di-(2-tert-butyl peroxy isopropyl) benzene (DTBPIB) peroxide as the cross-linking agent. Modification of the EVA/TPU blends via dynamic crosslinking significantly improves the tensile strength and modulus of the system and the improvement is more significant for EVA/TPU 50/50 and 60/40 blends. AFM study shows that crosslinked EVA particles are dispersed in the continuous TPU matrix and the dispersed EVA domain sizes are relatively smaller in EVA/TPU 50/50 and 60/40 blends leading to good mechanical properties. FTIR spectroscopy has been used to characterize the specific chemical changes occurring due to dynamic vulcanization. This TPV has excellent retention of physicomechanical properties even after reprocessing twice and the blends also have very good thermal resistance as indicated by aging study. The samples were found to exhibit remarkable improvement in oil resistance property as compared to their uncrosslinked counterpart. The creep behavior of the blends significantly improves after dynamic crosslinking and blends with higher TPU content show better creep resistance. Volume resistivity of all the peroxide vulcanized blends is in the range of 10 13 ohm cm, which is suitable for cable sheathing application.

Enhancement of thermal, morphological, and mechanical properties of compatibilized based onPA6‐enriched graphene oxide/EPDM‐g‐MA/CR: Graphene oxide andEPDM‐g‐MAcompatibilizer role

“…The properties of the materials undergoing the dynamic curing process are very different from those of similar noncured mixtures. By dynamic curing, the properties of the finished product are greatly improved 11–14 . Despite all these interpretations, the PA6/chloroprene rubber (CR) blend, including nanocomposite hybrid rubber, are incompatible and immiscible.…”

“…By dynamic curing, the properties of the finished product are greatly improved. [11][12][13][14] Despite all these interpretations, the PA6/chloroprene rubber (CR) blend, including nanocomposite hybrid rubber, are incompatible and immiscible. For this reason, a compatibilizers is used for the process of compatibility in blends to obtain the desired mechanical properties.…”

Radiation crosslinked Polyolefinic blends: exploring thermally tuned dual Shape Memory character

“…This might be due to the formation of C‐C linkage in both EOC and EPDM phases upon exposure to electron beam radiation. In presence of electron beam, the highly reactive radicals or ions that are produced modify the molecular structure of polymeric material and forms insoluble chemical crosslinks between the polymer chains . On the other side, in some cases degradation or polymeric chain scission can take place in presence of electron beam radiation also.…”

Fabrication of self‐healable thermoplastic polyurethane by masterbatch technology

“…An intense peak at 3341 cm À1 was observed in both TPU and CC0 due to the N H stretching vibration of urethane linkage. 62,63 In CC0, the N H peak intensity (stretching vibration) was slightly reduced relative to 3341 cm À1 because of interfacial crosslinking between TPU and EVA via urethane linkage at the mixing temperature. 52 However, the variation was not too prominent because the extent of crosslinking in the melt was low due to restricted diffusion and a much lower concentration of EVA compared to TPU.…”