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Thermally Cross-Linked and Sulphur-Cured Soft Tpvs Based on S-EB-S and S-SBR Blends
Thermally Cross-Linked and Sulphur-Cured Soft Tpvs Based on S-EB-S and S-SBR Blends
Wednesday, October 14, 2015: 9:00 AM
Thermoplastic vulcanizate (TPV) is a specific group of elastomer alloy (EA), in which the rubber phase is
selectively cross-linked by dynamic vulcanization and dispersed in the presence of a molten
thermoplastic phase under intensive mixing. The development of binary blends, utilizing melt-blending
technology of poly[styrene-b-(ethylene-co-butylene)-b-styrene] triblock copolymer (S-EB-S) and
solution-polymerized styrene butadiene rubber (S-SBR) were investigated, as were the characteristic
differences of these blends compared to other soft TPVs. Design of experiments (DOE) has been
adopted to execute the optimum processing conditions in terms of mixing temperature, rotor speed and
time of mixing by utilizing the Taguchi's L9 methodology, and the measure of confidence has been
accomplished using standard statistical technique of the analysis of variance (ANOVA). A novel, thermally
cross-linked (TCL) TPV has emerged as a by-product of DOE. Thereafter, meticulous analysis and
characterization have been conducted to understand the newly developed TPV system. Furthermore,
both semi-efficient vulcanizate (SEV) and efficient vulcanizate (EV) sulphur-based curing systems have
been designed by adopting the optimized processing conditions to cure the rubber phase, and a
comparative study has been organized among the TCL, SEV and EV systems. Dynamic mechanical
analysis (DMA) has revealed reduced rolling resistance for EV-cured TPVs compared to SEV- and TCLcured
systems, while still maintaining good wet grip by comparing the lost tangent values. Theoretical
calculation of viscoelastic properties by adopting the Kerner model predicts primarily co-continuous
morphology for the TPV systems, which is in good accordance with the experimental and morphological
observations.
selectively cross-linked by dynamic vulcanization and dispersed in the presence of a molten
thermoplastic phase under intensive mixing. The development of binary blends, utilizing melt-blending
technology of poly[styrene-b-(ethylene-co-butylene)-b-styrene] triblock copolymer (S-EB-S) and
solution-polymerized styrene butadiene rubber (S-SBR) were investigated, as were the characteristic
differences of these blends compared to other soft TPVs. Design of experiments (DOE) has been
adopted to execute the optimum processing conditions in terms of mixing temperature, rotor speed and
time of mixing by utilizing the Taguchi's L9 methodology, and the measure of confidence has been
accomplished using standard statistical technique of the analysis of variance (ANOVA). A novel, thermally
cross-linked (TCL) TPV has emerged as a by-product of DOE. Thereafter, meticulous analysis and
characterization have been conducted to understand the newly developed TPV system. Furthermore,
both semi-efficient vulcanizate (SEV) and efficient vulcanizate (EV) sulphur-based curing systems have
been designed by adopting the optimized processing conditions to cure the rubber phase, and a
comparative study has been organized among the TCL, SEV and EV systems. Dynamic mechanical
analysis (DMA) has revealed reduced rolling resistance for EV-cured TPVs compared to SEV- and TCLcured
systems, while still maintaining good wet grip by comparing the lost tangent values. Theoretical
calculation of viscoelastic properties by adopting the Kerner model predicts primarily co-continuous
morphology for the TPV systems, which is in good accordance with the experimental and morphological
observations.