• Elastomers and Composites
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• 제18권4호
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• pp.135-139
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• 1983

Scanning electron microscopy studies were conducted to examine the surface treatment effects of treating agents the proposed in the previous studies on various vulcanizates. Fracture surfaces of the vulcanizates compounded with kaolin treated with sodium polyphosphate of poly(maleic anhydride) presented favorable results as expected from the results of the previous studies. In other words, treating agents such as sodium polyphosphate and poly(maleic anhydride) show considerable reinforcing effects on the vulcanizates.

• 한국환경과학회지
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• 제10권1호
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• pp.73-77
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• 2001

This study examined blends of styrene butadiene rubber(SBR) and chloroprene rubber(CR) prepared from an open 2-roll mill following the conventional polymer blend method for a wide range of the blend composition. Rubber vulcanizates were manufactured by hot press and then mechanical properties, heat and ozone resistance of the specimens were examined. Due to the post cure during the aging test, hardness of vulcanizates was increased. It was found that the undesirable characteristics of heat and ozone resistance of pure SBR was significantly improved through the blending of SBR with CR.

• Elastomers and Composites
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• 제38권2호
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• pp.167-174
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• 2003

Thermoplastic vulcanizates (TPV) or dynamic vulcanizates are thermoplastic elastomers produced by simultaneous mixing and crosslinking of a rubber and a thermoplastic. The objective of the present work is to investigate the effects of different types of peroxides as curing agents on the properties of PP/EPDM TPVs. The mechanical properties change significantly with the chemical nature of the peroxides and the extent of crosslinking at a fixed PP/EPDM blend ratio. The tensile strength of the TPVs obtained with the various peroxides can be related to the solubility parameters of the polymers and of the peroxides. The Young's modulus of the peroxide-cured TPVs can be correlated with the delta torque values of equivalent thermoset EPDM vulcanizates, corresponding to the crosslinking efficiencies of the peroxides.

• Elastomers and Composites
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• 제17권1호
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• pp.13-21
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• 1982

The purpose of this dissertation is to compare bound andtioxidant, MHPPD with the ordinary one, IPPD, when high polymers are used like NR and SBR. The effect of rubber bound antioxidant and ordinary antioxidant on the Mooney scorch time has been studied by means of the Mooney viscometer. The ageing properties of vulcanizates containing rubber-bound antioxidant and ordinary antioxidant have been studied in terms of hardness, tensile strength and elongation. The results of the Mooney scorch time and ageing properties are as follows: When MHPPD was mixed with NR or SBR compounds, the Mooney scorch time was faster than the IPPD compounds. Also the ageing properties of the vulcanizates containing MHPPD were much superior to the IPPD compounds. Furthermore, the vulcanizates comporised of MHPPD have taken andvantage of and resistance in the ozone test.

• Elastomers and Composites
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• 제30권3호
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• pp.207-217
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• 1995

The reinforcement of Inorganic filler silica treated with LBR-MDI In SBR vulcanizates were Investigated. The inorganic filler silica treated with MDI on unmodified surface and that of silica treated by MDI was retreated with LBR. The charateristics of vulcanization, physical properties, surface properites and dynamic properties were investigated after mixing those silica with SBR and unmodified silica with SBR. Rheometric studies of the vulcanization showed that S-series has fast scorch $time(t_{10})$ and an optimum cure $time(t_{90})$ in the SBR compounds. And it was turned out that SBR vulcanizates compounded with LBR treated silica was better than any other componnds in hardness, tensile strenght, 100 300% modula and elongation. We could confirm that urea bonding is formed from IR spectrum. We concluded that L-series shows the best reinforcement effect in SBR vulcanizates.

• Elastomers and Composites
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• 제55권4호
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• pp.281-288
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• 2020

A calibration curve is needed to determine the SBR and BR blend ratio of SBR/BR blend rubber compounds using pyrolysis-gas chromatography/mass chromatography (Py-GC/MS) or Py-GC. In general, a calibration curve is obtained using reference SBR/BR vulcanizates with various blend ratios. In this study, the calibration curves were obtained using reference samples made of rubber solutions and were compared to those plotted using the reference SBR/BR vulcanizates. Calibration curves using variations of 1,3-butadiene/styrene, 4-vinylcyclohexene (VCH)/styrene, 2-phenylpropene (PhP)/butadiene, PhP/VCH, 4-phenylcyclohexene (PhCH)/butadiene, and PhCH/VCH ratios with the BR content were examined for the suitability. We found that the calibration curves obtained using the mixed rubber solution references (1,3-butadiene/styrene and PhP/butadiene) could replace those constructed using the reference SBR/BR vulcanizates. The calibration curves of 1,3-butadiene/styrene and PhP/butadiene obtained using the raw references can be used for the determination of the SBR/BR blend ratios by applying some correction factors.

• Bulletin of the Korean Chemical Society
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• 제19권10호
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• pp.1121-1124
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• 1998

• Elastomers and Composites
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• 제44권4호
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• pp.401-407
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• 2009

용액중합 스티렌-부타디엔 고무 컴파운드 가교체의 균열저항성 및 마모특성에 미치는 공정오일의 영향을 조사하기 위해 방향족 고리화합물(PCA) 성분을 다량 함유하고 있는 방향족 오일과 저 PCA 오일을 선택하였다. 인장강도 및 인열강도 결과에 의하면 방향족 오일함유 컴파운드가 저 PCA 오일함유 컴파운드에 비해 우수한 물성을 나타내었다. 또한 방향족 오일함유 컴파운드가 균열저항성이 월등히 우수하였고, 특히 인열에너지가 낮은 범위에서 더 우수한 결과를 나타내었다. 마모저항특성은 마찰에너지가 낮은 범위에서는 방향족 오일함유 컴파운드가 우수한 결과를 나타낸 반면, 높은 마찰에너지 범위에서는 저 PCA 오일 함유 컴파운드가 오히려 높은 저항성을 나타내었다.

• Elastomers and Composites
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• 제42권3호
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• pp.168-176
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• 2007

카본블랙이나 실리카 등으로 보강된 고무 가황체는 순수한 초기상태에서 하중(부하)를 가하고 제거하는 반복과정에서 응력은 점점 연화되어 초기상태에서 얻어진 응력보다 작게 나타난다. 이러한 응력 연화 현상을 Mullins 효과라고 부른다. 이러한 응력 연화 거동을 이론적으로 표현하기 위하여 Ogden-Roxburgh 등이 손상 파라미터를 이용하여 제안한 pseudo-elastic 개념을 적용하여 보강제가 함유된 고무 가황체의 변형률 에너지 함수를 구하였다. 카본블랙으로 보강된 NR 가황체를 이용하여 준정적 반복 부하 시험을 실시하였으며, pseudo-elastic 모델에서의 손상 파라미터가 제하 및 재 부하 시 응력-변형률 곡선에 어떠한 영향을 주는가와 더불어 손상 파라미터의 두 가지 변수인 r과 m의 물리적 의미를 파악하였다. 또한 보강제 함량을 달리하여 제작한 고무 가황체의 응력연화 변형률 에너지 함수를 결정하고 비교하였다.

• Elastomers and Composites
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• 제40권2호
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• pp.112-118
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• 2005

실란 커플링제가 카본블랙과 점토로 보강된 천연 고무 가황물의 회복 특성에 미치는 영향에 대해 연구하였다. Bis-(3-(triethoxysilyl)-propyl)-tetrasulfide (TESPT)를 실란 커플링제로 사용하였다. 실란 커플링제가 함유된 가황물은 실란 커플링제가 함유되지 않은 가황물에 비해 전반적으로 빠른 회복 거동을 보였다. 그러나, 점토 함량이 높은 가황물의 경우 $-20^{\circ}C$보다 낮은 온도에서는 실란 커플링제가 함유된 가황물이 실란 커플링제가 함유되지 않은 가황물에 비해 느리게 회복되었다. 실란 커플링제가 함유된 가황물과 실란 커플링제가 함유되지 않은 가황물의 회복량 차이는 점토 함량이 증가할수록 감소하였다. 실험 결과는 가교 밀도, 모둘러스, 그리고 결합 고무량으로 설명하였다.