• Elastomers and Composites
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• v.37 no.1
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• pp.14-20
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• 2002

Silica-filled rubber compound needs longer mixing time compared to carbon black-filled one since it has poor dispersion or the filler. Influence of the mixing procedure on the properties of natural rubber compound filled with both silica and carbon black was studied. The discharge temperature of the master batch (MB) mixing was $150^{\circ}C$. The mixing time was longer when silica and carbon black were loaded separately than when loaded simultaneously. The mixing time was longer when silica was loaded first than when carbon black is loaded first. The compounds prepared by one MB step (conventional mixing) were compared with the compounds prepared by two MB steps (two-step mixing). Scorch times of the two-step mixing compounds were longer than those by the conventional mixing ones. Bound rubber contents of the formers were lower than those of the tatters. The two-step mixing vulcanizates had longer elongation at break, higher tensile strength, and better fatigue life.

• Rubber Technology
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• v.12 no.1
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• pp.8-16
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• 2011

• Elastomers and Composites
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• v.22 no.2
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• pp.156-171
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• 1987

• Elastomers and Composites
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• v.21 no.3
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• pp.226-247
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• 1986

• Elastomers and Composites
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• v.13 no.2
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• pp.126-132
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• 1978

SBR 백색(白色) 배합(配合)고무의 일광변색(日光變色)은 노방제(老防劑)나 연화제(軟化劑)의 종류(種類)와 양(量)에 의(依)한 영향보다는 가황제(加黃劑)나 촉진제(促進劑)의 종류(種類)에 큰 영향을 받으며, 특(特)히 가황(加黃)의 정도(程度)는 변색(變色)에 가장 큰 영향을 미친다.

• Journal of the Korean Chemical Society
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• v.41 no.10
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• pp.524-534
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• 1997

Analysis of additives in cured rubber is often a difficult task for analytical chemists because of a wide variety of complex components. Conventional analyses of additives and rubbers have been done in multistep, off-line processes with large sample size and extensive sample preparations. The coumarone-indene resin, resorcinol-formaldehyde resin, and prevulcanization inhibitor have been characterized by their pyrolysis pathways and mass spectra of characteristic pyrolyzates. Pyrolysis Gas Chromatography/Mass Spectrometry (Py-GC/MS) was used in the identification of additives without any sample pretreatment. This result shows that several organic additives in cured rubber can be directly analyzed.

• Elastomers and Composites
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• v.38 no.1
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• pp.72-80
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• 2003

Phosphoric ester compound was employed as thermal resistant and flame retardant for chlorinated polyethylene(CPE) rubber material which is used to prepare automotive oil cooler hose. Cure characteristics, physical properties, thermal resistance, and flame retardation of CPE rubber compounds were investigated. CPE rubber which has excellent properties such as cold resistance and chemical corrosion resistance, and is inexpensive in price than existing ethyleneacrylate rubber(EAR) was used to prepare a rubber compound useful for hose. A non-halogen flame retarding agent N,N'-bis- (diphenylphosphoro) diaminohexane(BDPDH), which is condensed phosphoric ester, was synthesized and it was mixed to CPE rubber material with the range of $0{\sim}30 phr$. From the test results, rheological properties, heat resistance, and flame retardance of CPE rubber compounds were found out to be much increased. The optimum content of BDPDH to rubber which gives maximum effect on thermal resistance and flame retardation, within the range of tolerable specification for rubber materials, was determined to be 20 phr.

• Journal of Adhesion and Interface
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• v.15 no.2
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• pp.49-56
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• 2014

In this study, properties of adhesion between adhesion promoter-containing rubber compound and zinc coated steel cord was investigated. Cobalt salt, resorcinol formaldehyde resin (RF resin) and hexamethoxymethylmelamine (HMMM) were used to adhesion promoter. Since cobalt salts accelerate sulphidation rate of zinc at zinc coated steel cord surface, pullout force of rubber compound applying cobalt salts was increased compared to that of rubber compound without applying cobalt salts. Pullout force and rubber coverage of rubber compounds applying all adhesion promoters were superior because strong interlocking between rubber matrix increased modulus due to applying RF resin and HMMM and grown zinc sulfides at zinc coated steel cord surface.

• Polymer(Korea)
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• v.24 no.2
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• pp.220-227
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• 2000

Silica and carbon black filled natural rubber (NR) vulcanizates were prepared with different mixing modes and amounts of fillers. Curing characteristics, morphology. and tear properties of the NR vulcanizates were investigated. The NR vulcanizates filled with silica and carbon black sequentially showed longer induction time ($t_2$), cure index ($t_{90}$ ), and lower maximum torque ($T_{max}$ ) than the NR vulcanizates filled with them simultaneously, during curing process. The former showed superior dispersion of fillers and tear properties to the latter. The NR vulcanizates containing 30 phr of silica showed excellent properties in the experimental range.

• The Korean Journal of Rheology
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• v.6 no.1
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• pp.66-74
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• 1994

천연고무의 소련효과를 높이기 위하여 사용되는 소련촉진제가 천연고무 배합물의 점도나 Couette 보정치와 같은 유변학적 특성에 미치는 효과를 살펴보았다. 소련촉진제로는 BAPS, PCTP 및 ADS계의 것이 사용되었다. 실험결과 소련 촉진제의 사용에 따라 고무의 분자량이 감소하고 전단 점도도 감소하였다. Coutte 보정치는 소련촉전제의 사용량이 증가 할수록 낮은 값을 나타냈으며 압출물의 팽창도 소련촉진제를 사용하는 경우감소하였다. 그 러나 사용된 소련촉진제들 간에는 큰 차이를 보이지 않았다.