• Macromolecular Research
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• 제14권3호
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• pp.261-266
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• 2006

Blends of silicone rubber (VMQ) and liquid crystalline polymer (LCP) were prepared using a melt blending technique in the presence and absence of glass fiber and coupling agents. The effect of glass fiber and coupling agents on the thermal, dynamic mechanical, morphological pro-perties and cure characteristics of VMQ/LCP blends were studied. The vinyl silane coupling agent showed a significant effect on the above mentioned properties of VMQ/LCP blends by reacting at the interface between VMQ and LCP. The viscosity of the VMQ/LCP blends decreased with the addition of a coupling agent. A substantial improvement in storage modulus of VMQ/LCP blends was observed in the presence of glass fiber and coupling agents. However, as a coupling agent vinyl silane proved to be better than amine for the VMQ/LCP-glass-containing blends. The thermal stability of the pure silicone rubber was higher than those of the blends. This high thermal stability of silicone rubber was attributed to the Si-O-Si bonds. However, the thermal stability of the blends decreased further in the presence of a coupling agent, possibly due to a decrease in blend crystallinity.

• Elastomers and Composites
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• 제53권3호
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• pp.109-123
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• 2018

The effect of the silica content on the state and properties of silica-filled styrene-butadiene rubber/butadiene rubber (SBR/BR) compounds containing coupling and dispersion agents was evaluated by varying the content of silica from 50 to 120 phr. Bis-[(triethoxysilyl)propyl] tetrasulfide (TESPT) and zinc 2-ethylhexanoate (ZEH) were used as the coupling and dispersion agents, respectively. The maximum silica content in the pristine material was 80 phr, which increased to 120 phr upon the addition of TESPT and ZEH. The incorporation of TESPT considerably improved most of the rubber properties due to its coupling action and the suppression of silica flocculation, while further addition of ZEH resulted in additional improvements. The properties of the rubber compounds with different silica contents can be fully explained either by an enhancement of the rubber-silica interactions or by their deterioration due to an excessive amount of silica aggregates.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 춘계학술대회논문집
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• pp.742-748
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• 2003

As for marine propulsion shafting system using 4 stroke diesel engine, it is common to apply reduction gear box between diesel engine and shafting with a view of increasing mechanical efficiency, which inevitably require elastic coupling due to avoid chattering and hammering inside of gear box. In this study, optimum method of rectifying propulsion shafting system in case of 750ton fishing vessel specially in a view of torsional vibration, is theoretically studied. After exchange of diesel engine and gear box, analysis result of torsional vibration get worse and so some countermeasure are needed. The elastic coupling is modified from present block type rubber coupling showing relatively high torsional stiffness to rubber coupling with two series elements directly connected. The vibration measurement using two laser torsion meters was done during sea trial, whose results are compared to those of calculation and verified.

• Elastomers and Composites
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• 제49권3호
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• pp.239-244
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• 2014

용매를 사용하지 않고 실리카와 실란커플링제의 반응을 투과 방식 휴리에 변환 적외선 분광법(FTIR)과 열중량 분석법(TGA)을 이용하여 조사하였다. 실란커플링제로 bis[3-(triethoxysilylpropyl) tetrasulfide] (TESPT)를 사용하였다. 미반응 TESPT를 제거한 후, FTIR로 화학 결합 형성을 분석하였고 TGA로 반응한 TESPT 함량을 결정하였다. 커플링제의 함량이 증가할수록 실리카에 결합한 커플링제의 양이 증가하였으나, 커플링제를 과량으로 첨가하면 커플링제 간의 축합반응에 의해 올리고머를 형성하였다. 실리카와 커플링제 그리고 고무의 결합을 확인하기 위하여 개질 실리카와 저분자량 액상 BR을 반응시켜 실리카-커플링제-BR 모델 복합체를 제조하여 화학 결합 형성을 조사하였다. 미반응 고무는 용매를 사용하여 제거하였고 FTIR과 TGA로 분석하였다. BR은 개질 실리카의 커플링제와 반응하여 화학 결합을 형성하였다. 실리카-커플링제-BR의 화학 결합 형성으로 인해 실리카 표면의 극성은 크게 낮아졌고 실리카 입자 크기는 커지는 효과를 보였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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• pp.206-209
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• 2002

The purpose of this research was to find influence of compounding materials on electrical properties of silicone rubber such as tracking characteristic. The tracking characteristic was tested through controlling the ATH, a widely use anti-tracking agent. Regarding the particle size and coupling agent of ATH, compound silicone rubber with ATH of coupling agent and larger diameter showed better anti-tracking properties. It can be included that ATH of coupling agent use vinyl silane, dispose of tracking characteristic was achieve excellant results.

• Bulletin of the Korean Chemical Society
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• 제22권10호
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• pp.1145-1148
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• 2001

• Elastomers and Composites
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• 제51권3호
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• pp.218-225
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• 2016

In order to examine correlation between silane coupling agent and activator which affects the physical properties of silica filled natural rubber compound, such as heat buildup, rebound property, dynamic mechanical and morphological properties were measured. With incorporation of silane coupling agent, $tan{\delta}$ at $0^{\circ}C$ was increased and at $60^{\circ}C$ was decreased, which resulted in improving of wet grip and rolling resistance. When silane coupling agent which is corresponding to 8~10% of silica was used, most favorable heat build up and $tan{\delta}$ was obtained. And also when activator was used, dispersibility of silica was improved as a result of reduction of reaggregation of silica.

• 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.

• 한국소음진동공학회논문집
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• 제13권12호
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• pp.923-929
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• 2003

As for the marine propulsion shafting system using 4 stroke diesel engine, it is common to apply a reduction gear box between diesel engine and shafting to increase propulsion efficiency, which requires inevitably a certain elastic coupling to avoid chattering and hammering inside of gear box. In this study, the optimum method of rectifying propulsion shafting system in case of 750 ton fishing vessel is theoretically studied in a view of dynamic characteristics of torsion. After the replacement of diesel engine and gear box, the torsional vibration get worse and so some countermeasures are needed. The elastic coupling is modified from a present rubber coupling of block type having relatively high torsional stiffness to a rubber coupling haying two serially connected elements. Torsional vibration damper was installed at crankshaft free end additionally and moment of inertia of flywheel was adjusted. The dynamic characteristics of shafting system was improved by these modification. The theoretical analysis of torsional vibration are compared to measurement results using two laser torsion meters during the sea trial.

• Elastomers and Composites
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• 제26권2호
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• pp.115-122
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• 1991

Polychloroprene rubber was moisture-cured after treating them with silane coupling agents such as 3-mercaptopropyltrimethoxysilane(MPS), 3-methacryloxypropyltrimethoxysilane(MAS) and vinyltriethoxysilane(VES), especially MPS. The cure reaction is composed of two steps. The first is the reaction between chlorine atoms of CR and silane coupling agents. The second is the formation of cross-links which are siloxane linkage. The linkage is formed by the condensation of silanol groups which are produced by the hydrolysis of alkoxysilyl groups. The first reaction was kinetically studied and the reactivity of CR to silane coupling agents was determined in previous literature. Crosslinking density and mechanical properties of the moisture-cured elastomer filled with silica or non-filled were studied and the feasibility of this cure system was discussed.