Effects of carbon blacks with various structures on vulcanization and reinforcement of filled ethylene-propylene-diene rubber

Abstract

The effects of carbon blacks on vulcanization and mechanical properties of filled ethylene-propylene-diene rubber (EPDM) are investigated, by comparing with five types of rubber-grade carbon blacks. Curing kinetics is studied by rheometer and the results indicate that the curing characteristics are influenced by combination of surface area of carbon black and sulphur content on the filler surface, because the former one enhances the physical cross-linking and the latter one introduces the additional chemical cross-linking. Both the degree of cross-linking and cure rate increase with increasing surface area and sulphur content, whereas the optimum cure time and scorch time decrease. The reinforcing nature of the carbon black is assessed from mechanical measurements. It is suggested that the surface area of carbon blacks strongly affects the physical properties of EPDM/carbon black composites. Conductive carbon black (N472) can be used as desirable reinforcing filler due to the higher degree of cross-linking of EPDM with N472 than other EPDM/carbon black composites. The morphology and distribution of particles are studied by using scanning electron microscope. The sound reinforcing ability of N472 is also supported by scanning electron microscope due to the notable dispersibility of N472 within EPDM matrix. N472 ensures the EPDM/N472 composite the most conductive sample among the five composites

Relationship between Cell Compatibility and Elastic Modulus of Silicone Rubber/Organoclay Nanobiocomposites

“…Decrease of the crosslinking density which was evaluated from cure curves cited that nanofiller acts as an inhibitor. In other words, addition of nanoparticles into a polymer matrix would prevent chemical crosslinking and causes physical integrity (25) with a strong interface between nanofiller and silicone rubber (26). Such integrity is achieved by uniform distribution of particles into the nanocomposite structure.…”

“…It could be attributed to how cells could spread on the substrates and what contact area they had on them which were both directly referred to different mechanical properties of membranes. In tissue engineering, the cell fate and maintenance of stem cells to different lineage such as osteogenic would be manipulated by many factors including chemical stimulations of osteogenesis conducted by various proteins (25) and physiological simulations such as presence of scaffolds that transfer mechanical signals of the environment (26). Considering this point, some functional nanobiocomposites that meet above conditions were designed for osteogenic differentiation.…”

“…Cytoskeletal arrangement and orientation is highly dependent on mechanical and structural properties of the matrix such as elastic modulus, Poisson's ratio, and roughness (25,26). When interact with substrate, cellular responses including relaxation time and adaptation by alteration in fibrous structure are defined by local matrix deformability (27,28).…”

“…When interact with substrate, cellular responses including relaxation time and adaptation by alteration in fibrous structure are defined by local matrix deformability (27,28). The adjustment of cell cytoskeleton to mechanical properties of the substrate roots in polymerization and depolimerization of actin fibers (29) which act via focal adhesion proteins at cellsubstrate interface (26).…”

Morphology and Physical Properties of EPDM Composites Containing Bottom Ash and Talc

“…내유성 및 접착성이 약하고 가황반응에 의해 기계적 강도가 약해지기 때문에 이러한 단점을 보완하기 위해 카본블 랙(carbon black), 실리카(silica), 글래스 비드(glass bead) 등과 같은 충진제를 첨가하여 복합소재를 제조하는 연구가 많이 진 행되고 있다 [2]. EPDM/카본블랙 복합소재에서 카본블랙은 EPDM의 물리적인 cross-linking을 촉진시키고 기계적 강도를 향상시킨다 [3]. 또한 EPDM/실리카 복합소재는 실리카가 열적 물성 및 내마모성을 향상시킨다고 보고되었다 [4].…”