• 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.

• Korean Chemical Engineering Research
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• v.56 no.3
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• pp.343-348
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• 2018

Each of the two polycarbonates (PC) of different molecular weights was blended with acrylonitrile-butadiene-styrene (ABS) under high-shear rate processing to afford PC/ABS. Sizes of ABS dispersed phases and mechanical properties of PC/ABS blends were investigated and high-shear rate processing of PC/ABS was carried out by changing screw speed and processing time. Prepared specimens were examined by scanning electron microscope (SEM) to observe morphology changes. Sizes of ABS dispersed phases in PC/ABS blends were observed to decrease gradually as screw speeds increased. Tensile strengths and elongations of specimens were investigated by universal testing method (UTM) to study the influence of molecular weight of PC exerting on PC/ABS blends. As a result, PC1/ABS blends (PC1: higher molecular weight PC) exhibited more strengthened properties than PC2/ABS (PC2: lower molecular weight PC). The tensile strength of PC1/ABS showed an increasing tendency when the screw speed increased, and the elongation did not show a significant decrease, but increased slightly with increasing shear time at a constant screw speed of 1000 rpm.

• Macromolecular Research
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• v.16 no.7
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• pp.620-625
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• 2008

A novel nitrogen-phosphorus compound, diphenyl piperazine-1,4-diylbis(methylphosphinate)(DPPMP) was synthesized via a two step reaction and its flame retarding efficiency as a single component additive was investigated. The success of synthesis was confirmed by FTIR and $^1H$ and $^{31}P$ NMR analysis. The product was mixed with polycarbonate (PC), poly(butylene terephtalate) (PBT), ethylene-vinyl-acetate copolymer (EVA), and acrylonitrile-butadiene-styrene copolymer (ABS). The flame-retarding efficiency was evaluated using the limiting oxygen index (LOI) and the UL-94 vertical test methods. The addition of DPPMP enhanced the flame retardancy of the polymers and the V-0 ratings were obtained for the polymers examined in this study at a loading of 7-30 wt%. The gas-phase flame retardancy mode of action was suggested for this material from the thermogrametry experiment results.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.206-207
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• 2006

This paper describes the dielectric analysis of several insulators for home appliances. The dielectric characteristics of ABS(acrylonitrile butadiene styrene) were tested in relative permittivity, dielectric loss($tan{\delta}$) and specific resistance and compared with those of the other 4 insulators of PE(polyethylene) series. As a result, the relative permittivity of only the ABS slightly decreased with temperature. In the case of the tan6, the ABS showed higher dielectric loss than the other insulators but more excellent thermal performance. In addition, its changing pattern in specific resistance was very similar to that in $tan{\delta}$.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.10
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• pp.1085-1091
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• 2014

We developed a single-channel thread sensor for a rotary bobbin by optical sensing and analyzed the signal characteristics. A specially designed mount made of ABS (acrylonitrile-butadiene-styrene) resin that encapsulated an optical sensor was fabricated by using a 3D printer and was attached to the rotary bobbin system. Stable control on a weaving machine was achieved by observing the difference in the output signals of an optical sensor system, which vary significantly according to the states of the thread in the weaving operation. The optical sensor effectively detects an unintentional thread cut and run-out during weaving fast enough to enable prompt stopping of the weaving machine, thereby minimizing the loss of expensive fabrics.

• The Journal of the Acoustical Society of Korea
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• v.38 no.3
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• pp.344-351
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• 2019

In this work, the mechanism of contraction and expansion noise generation is investigated, and effective methods are proposed to reduce the occurrence frequency of noise during operation of the refrigerator. First, the frequency spectrum analysis was made by using the sound pressure signal measured in an anechoic chamber to investigate the characteristic of noise and the frequency of occurrence. Second, a thermal deformation analysis was conducted to predict the location of noise source. It is found from the analysis that the biggest thermal deformation occurs in the middle of the left inner case in the freezer room. Following the investigation made, a noise reduction method is proposed. The method is proposed to reduce the contraction and expansion noise by reducing the thermal deformation through increasing ABS (Acrylonitrile Butadiene Styrene) thickness in the center of refrigerator.

• Polymer(Korea)
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• v.38 no.4
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• pp.471-476
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• 2014

Polycarbonate (PC) and acrylonitrile-butadiene-styrene (ABS) blends were prepared using a high shear extruder to investigate their thermal decomposition and mechanical properties with shear rate and shear time. In this experiment, high shear rate, from 1000 to 3000 rpm, in blending process was applied for 10 to 40 sec, respectively. At high shear rate over than 2000 rpm, the initial decomposition temperature was dropped significantly compared to a compounded sample because of thermal decomposition of the blend by high shear. Consequently, high shear processing gave an important effect on the mechanical and thermal properties of the PC/ABS blend. In particular, elongation of the blend decreased significantly with shear rate.

• Tribology and Lubricants
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• v.30 no.5
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• pp.278-283
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• 2014

Carbon nanotubes (CNTs) are used in various composite materials to enhance electrical, thermal and mechanical properties of composite materials. In this study, we investigate the wear characteristics of polycarbonate/acrylonitrile-butadiene-styrene (PC/ABS) blends containing multi-walled carbon nanotubes (MWCNTs). PC/ABS blends are commonly used in many industrial applications such as cellular phones and display cases and MWCNTs have been added to the PC/ABS blends to improve their electromagnetic interference shielding (EMS). We performed wear tests on PC/ABS blends containing MWCNTs under reciprocating linear sliding conditions with chrome steel balls as a counterpart material. The normal loads were 10, 30, 50, 70, 100 N, the sliding speed was 10 mm/s, the stroke length was 15 mm, and the tests lasted 900 s. The MWCNTs included in the PC/ABS blends lower the wear volume and friction coefficient of the composites. We analyzed the wear debris collected from the composites during the tests in terms of the MWCNT concentration using inductively coupled plasma optical emission spectroscopy. The results show that the quantity of MWCNTs in the debris is proportional to the concentration of MWCNTs in the composite, indicating that the exposure of the MWCNTs to environments by wear could be increased with their concentration in the composite.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.10
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• pp.59-67
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• 1999

The lead time for new products is very limited in the current manufacturing processes, therefore the Rapid Prototyping process has been introduced and generally used in the industry. Fused Deposition Manufacturing (FDM) is one of the most common methods in this field. In the FDM process, the patterns are made of Wax of ABS and ABS shows better quality of the patterns. To date, the FDM/ABS patterns are used in investment casting for making silicon moulds to produce was patterns because it is very difficult to dewax FDM/ABS directly. The aim of this paper was to propose a feasibility of using FDM/ABS parts as wax-pattern substitutes in the investment casting process. The effects of casting conditions, such as pre-heat temperature and casting temperature, are provided. Comparisons with the conventional investment casting processes using the wax-patterns under the same prototype are made. Lead-time and saving cost are discussed in using FDM/ABS parts as was-pattern substitutes compared with the products from other rapid prototype systems.

• Advances in nano research
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• v.14 no.2
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• pp.117-126
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• 2023

This experimental study investigated friction stir welding (FSW) of the acrylonitrile-butadiene-styrene (ABS) T-joint in the presence of various nano-silica levels. This study aim to handle the drawbacks of the friction stir welding (FSW) of an ABS T-joint with various quantity of nanoparticles and assess the performance of nanoparticles in the welded joint. Moreover, the relationship between the nanoparticle quantity and FSW was analyzed using response surface methodology (RSM) Box-Behnken design. The input parameters were the tool rotation speed (400, 600, 800 rpm), the transverse speed (20, 30, 40 mm/min), and the nano-silica level (0.8, 1.6, 2.4 g). The tensile strength of the prepared specimens was determined by the universal testing machine. Silica nanoparticles were used to improve the mechanical properties (the tensile strength) of ABS and investigate the effect of various FSW parameters on the ABS T-joint. The results of Box-Behnken RSM revealed that sound joints with desired characteristics and efficiency are fabricated at tool rotation speed 755 rpm, transverse speed 20 mm/min, and nano-silica level 2.4 g. The scanning electron microscope (SEM) images revealed the crucial role of silica nanoparticles in reinforcing the ABS T-joint. The SEM images also indicated a decrease in the nanoparticle size by the tool rotation, leading to the filling and improvement of seams formed during FSW of the ABS T-joint.