• Elastomers and Composites
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• v.24 no.3
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• pp.193-202
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• 1989

An experimental study of the development of carbon black dispersion by an internal mixer and its characterization is presented. We describe the measurement of carbon black agglomerate size and related characteristics using four different experimental techniques : optical microscopy, scanning elctrion microscopy, surface roughness, and electrical couductivity. The results from these different experiments are compared uning the same carbon black for a series of six different butadiene-styrene copolymers. The results from the different techniques are cross plotted and are critically discussed. It is found that surface but then sharply deteriorate. At subsequent stages of mixing optical microscopy seemed the most reliable measure.

• Journal of the Korean Solar Energy Society
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• v.21 no.2
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• pp.9-17
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• 2001

In this paper the attempts made by the authors to explore the feasibility of utilising concentrated solar beam radiation for joining engineering thermoplastics such as Acrylonitrilc/Butadiene/Styrene (ABS), Polycarbonate(PC) and Polymethylmethacrylate(PMMA) are presented. In addition, to study the joining of the materials, necessary experimentation with applying primer was performed. Tensile tests were conducted to determine the bond strength achieved at the specimen joint interface. Microscopic examinations of the fractured joints were performed in order to analyse the overall bond quality. Finally, the results in terms of bond strength achieved at the joint interface and energy consumed in the process were compared with those obtained with similar thermoplastic joining technique utilising microwave energy. In conclusion some advantages and limitations were outlined and necessary improvements of the jointing technique were recommended.

• The Korean Journal of Rheology
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• v.8 no.3_4
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• pp.177-186
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• 1996

압출가공으로 제조된 Polycarbonate(PC)/Acrylonitrile-Butadiene-Styrene(ABS) 블 렌드의 사출조건에 따른 모폴로지와 기계적 성질의 변화와 그 상관관계를 고찰하였다. 사출 온도와 금형온도가 높아질수록 분산상간의 coalescence 현상이 활발히 진행되었으며 이러한 모폴로지 변화로 인하여블렌드의 인장강도 굴곡강도 그리고 충격강도 등의 기계적 성질이 급격히 저하되었다. 사출온도와 금형온도의 증가에 따른 coalescence의 심화는 높은 온도에 서 연속상과 분산상의 점도가 저하되어 분산상 사이에 존재하는 연속상 성분의 배출이 보다 용이하게 이루어져 나타난 현상으로 설명된다. 실용적으로 특정한 상용화제가 투입되지 않 는 PC/ABS 블렌드를 사출공정을 거쳐 제품을 생산할 경우에는 급격한 모폴로지와 물성변 화가 일어나지 않는 범위에서 사출온도를 유지하는 것이 제품의 품질관리 측면에서 매우 중 요하다.

• Journal of Environmental Science International
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• v.10 no.1
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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.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10a
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• pp.497-502
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• 2000

This study was performed to change the latex content for properties of freezing-thawing resistance. When styrene-butadiene latex is added to portland cement, aggregate and water, a concrete with the color, consistency and workability of ordinary conventional concrete results, but with 20% to 35% less water. When cured, the concrete consists of hydrated cement and aggregate interconnected by a film of latex particles. In general, increasing the amount of latex will produce concrete with increased tensile and flexural strength and lower modulus of elasticity. Air entrainment has been used in conventional concrete for the past 50 years to impart freeze-thaw resistance. Latex modified concrete does not need additional air entrainment for freeze-thaw resistance provided adequate cure occurs.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.571-574
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• 2005

This study investigated the strength of concrete to improve construction material with polymer cement mortar. Some mixtures composed of Styrene-Butadiene Rubber(SBR) and Ethylene Vinyl Acetate(EVA) Poly Vinyl Alcohol(PVA) were studied. The three mixtures carried out the physical, mechanical test to determine its properties which a include : compressive, flexural, bond strength test. The test results show that the compressive strength was increased at long-term age when compared to early ages for increasing polymer contents. It was found that flexural strength and bond strength became larger as polymer to cement ratio became higher.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.793-797
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• 2005

This study was undertaken to examine the feasibility of recycling waste concrete fine aggregate to prepare polymer-modified mortars. The specimens of polymer-modified mortars were prepared by using styrene-butadiene rubber(SBR) latex and polyacrylic ester(PAE) emulsion as a polymer modifier. The formulations for specimens were prepared with various replacing ratios of waste concrete fine aggregates as parts of standard sand and various polymer cement ratios. For the evaluation of the performance of polymer-modified mortars, various physical properties were investigated. As a results, water cement ratio of polymer-modified fresh mortars increased with an increase of recycled fine aggregate, but decreased with an increase of polymer modifiers. The compressive and flexural strengths of polymer-modified mortars decreased with an increase of recycled fine aggregate, but flexural strengths increased with an increase of polymer modifiers.

• Journal of the Korean Ceramic Society
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• v.31 no.7
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• pp.745-752
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• 1994

A polymer reinforced grouts using ordinary portland cement mortar and water soluble polymer{polyvinyl alcohol(PVA), styrene-butadiene rubbre(SBR), etylene-vinyl acetate copolymer(EVA)} were made. The mechanical properties of the hardened specimens were investigated through the observation of the microstructure and application of fracture mechanics. When the PVA, SBR and EVA was added with 1.5 wt% to the grouts, the compressive strength were about 54 MPa, 63 MPa and 68 MPa respectively, and the flexural strength was about 11 MPa, 12.8 MPa, and 13.6 MPa respectively, and Young's modulus was about 3.8 GPa, 4.4 GPa and 4.6 GPa respectively, and critical stress intensity was about 0.73 MNm-1.5, 0.85 MNm-1.5 and 0.9 MNm-1.5 respectively. It can be considered that the strength improvement of polymer mortar grouts may be due to the removal of macropores and the increase of various fracture toughness effects, such as grain bridging, frictional interlocking and polymer bridging.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.592-596
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• 2001

A TACUB jig was applied to separate waste plastics [polystyrene (PS), acrylonitrile butadiene styrene (ABS), and polyethylene terephthalate (PET)] used in copy machine. The effect of water pulsation including amplitude and frequency on the separation performance was investigated for the feeds containing two or three plastics. Good results are obtained under suitable conditions. Grades of 99.8% PS,99.3% ABS, and 98.6% PET are recovered as the products in the upper, middle and bottom layers respectively. Based on these results, a processing plant fer recycling of plastics from scrapped copy machines is now under construction.

• Elastomers and Composites
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• v.52 no.1
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• pp.17-21
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• 2017

The optimum mixing conditions of silica and silane containing rubber composites were evaluated by investigating the properties of rubber composites prepared with a silica composition of 10, 20, 40, 60, and 80 g, respectively. The crosslinking rate decreased with increasing silica content, with he promoters being adsorbed on the silica surface with in the rubber composite. As a result, the increase in crosslinking time resulted in the destruction of the silica structure. The increase of the bound rubber content due to the destruction of the silica structure inhibited the chain motion of the polymer molecules and reduced the cohesion of the silica itself. Finally, the increase of silica content showed the increase of hardness, tensile strength, and storage modulus of rubber composites.