• Journal of Electrochemical Science and Technology
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• 제2권1호
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• pp.51-56
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• 2011

We develop a new nonwoven composite separator for a safer lithium-ion battery, which is based on coating of silica ($SiO_2$) colloidal particles/styrene-butadiene rubber (SBR) binder to a poly(ethylene terephthalate) (PET) nonwoven support. The $SiO_2$ particles are interconnected by the SBR binder and closely packed in the nonwoven composite separator, which thus allows for the development of unusual porous structure, i.e. highly-connected interstitial voids formed between the $SiO_2$ particles. The PET nonwoven serves as a mechanical support that contributes to suppressing thermal shrinkage of the nonwoven composite separator. The $SiO_2$/SBR content in the nonwoven composite separators plays an important role in determining their separator properties. Porous structure, air permeability, and electrolyte wettability of the nonwoven composite separators, in comparison to a commercialized polyethylene (PE) separator, are elucidated as a function of the $SiO_2$/SBR content. Based on this understanding of the nonwoven composite separators, the effect of $SiO_2$/SBR content on the electrochemical performances such as self-discharge, discharge capacity, and discharge C-rate capability of cells assembled with the nonwoven composite separators is investigated.

• Carbon letters
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• 제27권
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• pp.72-80
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• 2018

In the present work, a comparative study of the mechanical behavior of two series of elastomeric composites, based on carboxylated styrene butadiene rubber (X-SBR) and reinforced with rice bran carbon (RBC) and graphite, is reported. Hybrid composites of X-SBR filled with RBC-graphite were also investigated in terms of the cure characteristics, hardness, tensile properties, abrasion resistance, and swelling. It was observed that the cure times decreased with the incorporation of a carbon filler whereas the torque difference, tensile strength, tensile modulus, hardness, and swelling resistance increased compared to the neat X-SBR revealing a favorable characteristic of crosslinking. Dynamic rheological analysis showed that the G' values of the composites, upon the addition of RBC-graphite, were changed to some extent. This demonstrates that the presence of a strongly developed network of fillers will ensure a reinforcing characteristic in a polymer matrix.

• 멤브레인
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• 제24권6호
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• pp.463-471
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• 2014

폴리스티렌계 음이온교환막은 제조가 쉽고 공정이 간단한 장점을 갖고 있으나 막의 취성이 높아 내구성이 떨어지는 단점을 가지고 있다. 이를 보완하여 유연하고 우수한 내구성을 갖는 막을 만들기 위해 acrylonitrile-butadiene rubber를 첨가제로 사용하여 음이온교환막을 제조하였다. 다양한 조성의 vinylbenzylchloride와 styrene, divinylbenzene, acrylonitrile-butadiene rubber 그리고 benzoyl peroxide로 이루어진 단량체 용액을 지지체인 직물 형태의 지지체인 poly(propylene)위에 캐스팅 후 열중합 가교시킨 다음 trimethylamine과 acetone을 이용하여 음이온 교환기($-N+(CH_3)_3$)를 함유하는 복합막을 제조하였다. 음이온 교환막 제조시 첨가제의 함량에 따른 막의 성능을 평가하여 최적화 비율을 찾고, 단량체의 함량을 변화하여 함수율, 이온교환용량(IEC) 및 전기저항 값을 측정하였다. 그 결과 최적화 비율로 제조된 막들은 아스톰사의 상용화 음이온 교환막(AMX)보다 높은 IEC와 낮은 전기저항 값을 나타내는 동시에 유연성과 내구성이 우수한 막이 만들어진 것을 확인할 수 있었다.

• Macromolecular Research
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• 제8권6호
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• pp.285-291
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• 2000

Influence of silane coupling agent, bis-(3-(triethoxisilyl)-propyl)-tetrassulfide, on cure characteristics and bound rubber content of filled styrene-butadiene rubber (SBR) compounds and on physical properties of the vulcanizates was studied. Carbon black-filled and silica-filled compounds were compared. Content of the bound rubber increased with increased content of the silane coupling agent and this trend was shown more clearly in the silica-filled compounds. Optimum cure time of the carbon black-filled compound increased with increase of the silane content, while that of the silica-filled one decreased. Cure rate of the carbon black-filled compound became slower as the silane content increased while that of the silica-filled one became faster. By increasing the silane content, the minimum torque decreased and the delta torque increased. Physical properties of the silica-filled vulcanizate were found to be improved by adding the silane coupling agent. However, for the carbon black-filled vulcanizates, the tensile strength and tear resistance decreased with increase of the silane content. The differences between the carbon black-filled and silica-filled compounds were explained by difference in the reactivities of the fillers with the silane.

• 분석과학
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• 제22권5호
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• pp.355-359
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• 2009

An enzyme electrode bound by rubber solution was newly constructed and the test of its practicability were carried out. The binder of carbon powder was styrene-butadiene rubber dissolved in toluene and enzyme source was ground tissue of cabbage root. Volatilization of the solvent made the electrode material possess a mechanical robustness and a fast signal appearance. The electrode showed electrochemically irreversible characteristics and a powerful catalytic power (detection limit=$5.0{\times}10^{-5}M$, S/N=2). The double reciprocal plot of signal current and substrate concentration was ideally linear and the symmetry factor and exchange current density of the electrode used in this work were 0.35 and $4.93{\times}10^{-5}Acm^{-2}$ respectively.

• Elastomers and Composites
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• 제50권3호
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• pp.196-204
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• 2015

Crosslink density of a rubber vulcanizate determines the chemical and physical properties, while bound rubber is an important factor to estimate reinforcement of a filled rubber compound. Extender oil is added to a raw rubber with very high molecular weight for improving processability of a rubber composite. Influence of extender oil on crosslink density, bound rubber formation, and physical properties of solution styrene-butadiene rubber (SSBR) composites with differing microstructures was investigated. Crosslink densities of non-oil-extended SSBR (NO-SSBR) vulcanizates were higher than those of oil-extended SSBR (OE-SSBR) ones. Bound rubber contents of NO-SSBR compounds were also greater than those of OE-SSBR ones. The experimental results could be explained by interfering of extender oil. The OE-SSBR vulcanizates had low modulus but long elongation at break, whereas the NO-SSBR ones had high modulus but short elongation at break. It was found that the crosslink densities affected the physical properties more than the bound rubber contents. The moduli increased with increase in the crosslink density irrespective of extender oil, while the elongation at break decreased. Each variation of the tensile strengths of NO-SSBR and OE-SSBR vulcanizates with the crosslink density showed a decreasing trend. Tear strength of the OE-SSBR vulcanizate increased with increase in the crosslink density, whereas variation of the tear strength of NO-SSBR vulcanizate with the crosslink density showed a weak decreasing trend.

• Elastomers and Composites
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• 제38권2호
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• pp.122-127
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• 2003

환경에 유해한 PVC 재질의 바닥재나 시트를 대체하기 위하여 styrene-ethylene-butadiene-styrene(SEBS)과 같은 열가소성고무를 사용하고 polypropylene(PP) 등의 폴리머와 오일, 무기물 및 안정제 등을 혼합하여 내충격성 또는 탄성이 우수한 새로운 소재를 개발하기 위한 컴파운딩 연구를 진행하였다. SEBS와 오일의 혼합물에서 경도는 오일의 함량이 증가함에 따라서 선형적으로 감소하였고, SEBS/oil/PP의 조성물에서는 PP의 함량이 증가하면 인장강도는 선형적으로 증가하는 반면, 신율은 PP가 50phr상에서는 거의 영향이 없었다. PVC 소재의 바닥재나 시트를 대체 사용하기 위한 실질적인 SEBS 혼합물의 조성물에서도 인장 및 인열강도, 그리고 경도는 PP 함량에 비례하여 증가하는 것으로 나타났으나, 용융지수는 PP 함량이 증가하면 감소하는 것으로 나타났다.

• Elastomers and Composites
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• 제50권4호
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• pp.304-313
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• 2015

In this study, the anionic emulsified asphalt was prepared by dispersing asphalt particles evenly into water with combination of anionic and nonionic surfactants. Effects of NaOH and $CaCl_2$ on the phase stability of the emulsified asphalt were also investigated through zeta potential value and rheology behavior; the emulsified asphalt added with NaOH and $CaCl_2$ showed higher zeta potential value than that the asphalt with addition of only anionic and nonionic surfactants. In addition, with regard to shear thinning behaviors, it was found that pH of the emulsified anionic asphalt and $Ca^{2+}$, counter ion, affected the phase stability. SBR (styrene-butadiene-rubber) latex, EPD (water dispersed Epoxy), PU (polyurethane) and RI-10S, SBS (styrene-butadiene-styrene)-based property improvement additive, were used and studied to enhance the adhesion properties with the aggregates. RI-10S, however, was found to be only compatible with the anionic emulsified asphalt; the coating rate, adhesion and compression strength were increased with the RI-10S content.

• Carbon letters
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• 제10권4호
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• pp.320-324
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• 2009

We investigated the effect of diameter and content of carbon nanotubes (CNTs) on the physical properties of styrenebutadiene rubber (SBR)/CNTs nanocomposites. CNTs-reinforced SBR nanocomposites were prepared by the melt mixing process. CNTs with different diameters were synthesized by the chemical vapor deposition method (CVD). In this work, the mechanical property and other physical properties of SBR/CNTS nanocomposites were discussed as a function of the content and diameter of CNTs.

• Elastomers and Composites
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• 제44권3호
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• pp.252-259
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• 2009

양기능성실란(TESPD)이 실리카가 함유된 SBR 복합 소재에 첨가되었을 시 그에 따른 가교특성, 가공정도, 물리적 특성들에 미치는 영향을 조사하였다. TESPD를 첨가한 SBR 복합 소재는 TESPD가 실리카와 고무를 화학적으로 결합하여 3차원적인 구조를 형성함으로해서 가교밀도가 증가하였고, 이에 따라 기계적 강도가 증가하였다. 이는 또한 TESPD를 첨가하지 않은 소재와 비교했을 시 가공성이 증가하였다.