• Elastomers and Composites
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• 제57권4호
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• pp.188-196
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• 2022

Styrene-butadiene rubber(SBR) is a copolymer of styrene and butadiene. It is composed of 1,2-unit, 1,4-unit, and styrene, and its properties are dependent on its microstructure. In general, rubber composites contain a single rubber or a blended rubber. Similarly, SBR is used by mixing with natural rubber(NR) and butadiene rubber(BR). The composition of a rubber article affects its physical and chemical properties. Herein, an analytical method for determining the microstructure of SBR using via pyrolysis is introduced. Pyrolysis-gas chromatography/mass spectrometry is widely used to analyze the microstructure of polymeric materials. The microstructure of SBR can be determined by analyzing the principal pyrolysis products formed from SBR, such as 4-vinylcyclohexene, styrene, 2-phenylpropene, 3-phenylcyclopentene, and 4-phenylcyclohexene. An analytical method for determining the composition of SBR/NR, SBR/BR, and SBR/NR/BR blends via pyrolysis is introduced. The composition of blended rubber can be determined by analyzing the principal pyrolysis products formed from each rubber component.

• 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.

• Elastomers and Composites
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• 제33권4호
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• pp.246-254
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• 1998

Styrene butadiene rubber (SBR)/ 카렬블랙 복합체의 전기저항 특성과 전기전도 특성을 연구하기 위하여 표면저항, 체적저항, point to point 저항, 정전하 소멸시간 및 전기전도 실험을 4종의 카본블랙을 사용하여 실시하였다. 약 50phr의 카본블랙이 첨가되었을 때, 모든 저항값이 급격히 감소하는 임계영역 (Rc)을 나타내었다. 카본블랙이 첨가된 SBR 복합체의 전류밀도는 전기장의 증가에 따라 증가하며, 기울기 (dJ/dE)가 증가하는 임계점 (Pc)이 존재하였으며, 이때의 전기전도기구는 임계점을 기준으로 하여 낮은 전기장 영역에서는 ohmic 전도, 높은 전기장 영역에서는 공간전하 제한전도임을 알 수 있었다.

• Elastomers and Composites
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• 제34권2호
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• pp.121-127
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• 1999

스티렌-부타디엔 고무(styrene-butadiene rubber :SBR)의 가공성과 기계적 물성을 조절하는 방안의 일환으로, 고분자량 SBR(high molecular weight SBR : HM-SBR)과 저분자량 SBR (low molecular weight SBR : LM-SBR)의 혼합물의 특성을 조사하였다. HM-SBR/LM-SBR의 LM-SBR 함량이 증가함에 따라 경화전 혼합물의 Mooney 점도와 경화에 따른 토오크 증가치는 감소하고 가황 후 혼합물들의 Shore A 경도와 반발탄성율은 감소를 보였다. 또한 LM-SBR 함량의 증가에 따라 혼합물들의 가황 후 유리전이온도는 일정하지만 고무상태에서 tan ${\delta}$는 증가를 보였다. LM-SBR 함량에 따른 가황 전 혼합물들의 Mooney 점도 감소는 LM-SBR의 가소화 효과와 분자량 분포 증가에 기인하는 것으로 해석하였다. 가황 HM-SBR/LM-SBR 혼합물의 기계적 물성 변화는 고무 혼합물의 가교밀도 감소에 기인하는 것으로 판단되었다.

• Elastomers and Composites
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• 제56권3호
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• pp.172-178
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• 2021

The wear behavior of styrene-butadiene rubber (SBR) and butadiene rubber (BR) was investigated using a blade-type abrader with a steel blade (SB), Ti-coated tungsten carbide blade (TiB), or zirconia blade (ZB). The wear rate of SBR against SB and TiB decreased with increasing number of revolutions because of the blunting of the blades during wear. However, the wear rate of SBR against ZB remained nearly constant with little blade blunting. Generally, the wear rate of BR was largely unaffected by the blade material used for abrasion. The wear rate and frictional coefficient of SBR were found to be higher than those of BR at similar levels of frictional energy input. A power-law relationship was found between the wear rate and frictional energy input during abrasion. A well-known Schallamach pattern was observed for SBR, while a much finer pattern was observed for BR. The blade material affects the wear rate of the rubbers because the macromolecular free radicals and blade tend to undergo mechano-chemical reactions. The inorganic ZB was found to be the most inert for such a mechanism.

• Elastomers and Composites
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• 제54권4호
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• pp.335-344
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• 2019

In this work, styrene butadiene rubber (SBR) and styrene butadiene styrene (SBS) were used to modify asphalt, resulting in SBR- and SBS-modified asphalt, respectively. The two modified asphalts were emulsified with a nonionic emulsifier (Span 60) and cationic emulsifiers (ID, DDA) and their phase stabilization was investigated via particle size, Zeta potential, and flow behavior analysis. With increasing amount of the mixed emulsifier, the particle size decreased, leading to an increase in viscosity. The shear thinning behaviors and Zeta potential values ranging from 35-65 mV were determined and remained considerably stable. In addition, the adhesion strength and compression strength of the SBR-and SBS-modified asphalt emulsion were evaluated via surface free energy examination. The remarkable adhesion and compression strengths were estimated when 5 phr ID and 6 phr DDA were added to the emulsified asphalt modified with SBR and SBS. Therefore ID and DDA, the two cationic surfactants, played significant roles in improving the dispersion and interfacial adhesion strength, resulting in the improved adhesion and compression strength of the emulsified asphalts modified with SBR and SBS.

• Computers and Concrete
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• 제21권6호
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• pp.705-715
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• 2018

This paper presents an experimentally investigation pertinent to the mechanical properties of rubberized mortar (RM) with styrene-butadiene rubber (SBR). The SBR were used with constant water-to-cement ratio of 0.485 and two different volume proportion of SBR particles were utilized as aggregates. One types of SBR particles with fineness modulus of 4.951 were utilized 0%, 10%, and 20% of aggregate volume. Effectiveness of SBR replacement ratio, curing and aging effect on the compressive strength, flexural strengths as well as load-displacement. Compressive and flexural strength of concrete were investigated at the end of 28-days and 56-days age. Obtained results demonstrated that utilization of SBR reduced the flexural strength of SBR mortar at the earlier curing age while SBR increased. Moreover, mechanical properties of mortar mentioned above were significantly affected by the water cure timing with an increasing proportion of the replacement level of SBR.

• Elastomers and Composites
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• 제33권5호
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• pp.363-369
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• 1998

UV를 이용하여 반응성 모노머인 아크릴아미드를 SBR에 광그라프트 시키는데 있어서 주요한 인자인 모노머 농도, 조사시간 그리고 카본블랙의 함량이 모노머의 그라프트율에 미치는 영향을 살펴보았다. 광개시제로는 benzophenone을 사용하였다. 아크릴아미드의 그라프트율을 측정하기 위하여 FT-IR ATR과 증류수를 이용하여 정접촉각을 측정하였다. 아크릴아미드의 함량과 UV 조사시간이 증가함에 따라 그라프트율은 증가하였으며 또한 접촉각은 감소하는 현상을 나타내었다. SBR중 카본블랙 함량이 증가함에 따라 그라프트율이 증가함을 알 수 있었다.

• 고무기술
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• 제5권2호
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• pp.94-103
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• 2004

The present work describes modification of dual phase filler by electron beam irradiation in presence of multifunctional acrylates like trimethylol propane triacrylate (TMPTA) or silane coupling agent like bis (3-triethoxysilylpropyltetrasulphide) and in-fluence of the modified fillers on the physical properties of styrene-butadiene rubber (SBR) vulcanizates. Modulus at 300 % elongation increases whereas the tensile strength decreases with increase in radiation dose for the dual phase filler loaded styrene-butadiene rubber vulcanizates (SBR). However, modulus and tensile strength significantly increase, which is more, pronounced at higher filler loadings for TMPTA modified dual phase filler loaded SBR. These changes in properties are explained by the equilibrium swelling data and Kraus plot interpreting the polymer-filler interaction. Electron beam modification of the filler results in a reduction of tan ${\delta}$ at $70^{\circ}C$, a parameter for rolling resistance and increase in tan ${\delta}$ at $0^{\circ}C$, a parameter for wet skid resistance of the SBR vulcanizates. Finally, the influence of modified fillers on the properties like abrasion resistance, tear strength and fatigue failure and the improvement in the properties have been explained in terms of polymer-filler interaction.

• Macromolecular Research
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• 제9권1호
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• pp.45-50
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• 2001

Formation of bound rubber depends on the filler-polymer interactions including physical adsorption, chemisorption, and mechanical interaction. Bound rubbers consist of tightly and loosely bound ones. Styrene-butadiene rubber (SBR) is composed of styrene, 1,2-, cis-1,4-, and trans-1,4-units. Filler-polymer interactions of each components of SBR with fillers, carbon black and silica, were studied by analysis of microstructure of the bound rubber. Filler-polymer interaction of the 1,2-unit with the fillers was found to be stronger than those of the other components and this phenomenon was shown more clearly in the tightly bound rubber.