Vulcanizates of chlorobutyl rubber (CIIR) with the accelerated sulfur generally exhibit poor crosslinking density owing to the low level of unsaturation in the backbone of CIIR. Therefore, the sulfur cured CIIR shows inferior thermo-mechanical properties at elevated temperature. In addition to this, the vulcanization of CIIR with accelerated sulfur is limited at higher temperature due to reversion. To solve these problems, 4,4′-bis (maleimido) diphenyl methane (BMDM) was applied as a crosslinking additive along with the accelerated sulfur. The detailed curing studies have proved that the presence of BMDM greatly enhanced the rheometric torque and the reversion resistance while curing CIIR with accelerated sulfur even at higher vulcanization temperature. Moreover, the crosslinking densities of the sulfur cured CIIR have increased by 109% with the use of 1 phr BMDM and further rose to 380% with 5 phr BMDM. The improved crosslink density could enable reduction of the compression set of the sulfur cured CIIR to around 40% at 100 °C when it was vulcanized in the presence of 5 phr BMDM. The kinetic studies revealed that incorporation of this additive does not adversely affect the original vulcanization behavior of CIIR with accelerated sulfur, instead it marginally improved the speed of the vulcanization.

Flexible and stretchable electrodes have attracted immense attention because of their various electronic applications on the wearable sensing electronics, but challenges regarding robust and sustainable electrical performance under static and dynamic mechanical stresses still need to be overcome. Herein, with a simple effective strategy, a highly serviceable and flexible elastomeric electrode fabricated by utilizing an interpenetrating network between acrylic rubber (AR) and silicone rubber (SR), and silver (Ag) ink to increase electrical conductivity, is introduced. Oxygen (O2) plasma and sodium dodecyl sulfate (SDS) treatment on wrinkle substrate surface lead to robust adhesion of Ag ink layer, results in high electrical conductivity. Wrinkle morphology can help to stably maintain the continuous conductive Ag network during static and dynamic deformation. This stretchable electrode possessing properties such as robust and stable electrical conductivity of ~103 S/cm under 150% static tensile deformations and good sustainability after 1000 cycles of dynamic tensile deformations is a promising candidate for stretchable wearable electronics.

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