• Elastomers and Composites
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• 제35권3호
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• pp.227-235
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• 2000

신발스크랩으로부터 발생되는 폐우레탄 발포체(waste urethane foam)와 폐우레탄(waste urethane scrap, $5{\sim}7mm$)의 재활용을 위하여 첫째, 양액재배용 배지의 구성 요소로 사용하여 장미 재배 적용가능성을 조사하였으며, 둘째, 폐우레탄으로부터 재생우레탄(Recycled Thermoplastic Polyurethane : RTPU)을 제조하여 RTPU와 HIPS(High Impact Polystyrene)를 블렌드한 후 이의 적용성을 확장하기 위하여 RTPU/HIPS 블렌드물에 amine계 발포제를 사용하여 발포체를 제조하였다. 양액재배용 배지의 구성요소로서 폐고무의 재활용에 있어서는 식물의 성장에 영향을 미치는 pH, 전기전도도, 생육 등을 조사하였으며, 폐우레탄 발포체의 물성은 TGA, DSC, FT-IR, SEM등을 이용하여 조사하였다. 본 연구는 폐우레탄 재활용 가능성의 다각화에 목적을 두었다.

• 한국환경과학회지
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• 제22권6호
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• pp.687-694
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• 2013

To investigate organoclay, high styrene resin masterbatch (HSR), high impact polystyrene (HIPS), and polystyrene (PS) as reinforcing materials for the improvement of the abrasion resistance of poly(styrene-block-butadiene-block-styrene) (SBS), SBS/organoclay nanocomposites, SBS/HSR, SBS/HIPS, and SBS/PS blends were prepared. The effect of organoclay and blends on the abrasion resistance and mechanical properties of SBS was investigated. Even though intercalations of organoclay are observed for SBS/Cloisite 20A nanocomposites and not for SBS/Cloisite 30B composites, the abrasion resistance of SBS/Cloisite 20A nanocomposites is worse than that of SBS/Cloisite 30B composites. When SBS was blended with HSR, HIPS and PS, the abrasion resistance of the blends increases with increasing of HSR, HIPS and PS content from 0 to 20 wt%.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제53권6호
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• pp.305-311
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• 2004

Charge transport phenomena of polyaniline-DBSA/High Impact Polystyrene (PAM-DBSA/HIPS) blends have been studied through an examination of electrical conduction. HIPS used host polymer in the blends and PANI-DBSA obey a space charge limited conduction mechanism and a ohmic conduction mechanism respectively. However, PANI-DBSA/HIPS blends do not obey any classical conduction mechanism. Analysis of conduction mechanism revealed that the charging current of PANI-DBSA/HIPS blends increased with the increase of PANI-DBSA content. This result migrlt be explained by the reduction in the distance between PANI-DBSA particles enabling the charge carriers to migrate from a chain to a neighboring chain via hopping or micro tunneling. It was also found that the charging current of PANI-DBSA/HIPS blends decreased as the temperature was elevated, which is of typical phenomena in metals. It is speculated that the charge transport in PANI-DBSA particle was somewhat constrained due to strong phonon scattering.

• Tribology and Lubricants
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• 제31권3호
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• pp.95-101
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• 2015

Carbon nanotubes (CNTs) are widely used in polymer composites as filler materials to enhance various characteristics of the composites because of their remarkable mechanical, electrical, and thermal properties. In this study, we investigate the effects of MWCNTs on the electrical and wear characteristics of high-impact polystyrene (HIPS) composites, and compare the results with the effects of carbon black (CB). The HIPS composites are classified as Bare-HIPS, MWCNT-HIPS composites containing 2, 3, 4, and 5 wt% MWCNTs, and CB-HIPS containing 17 wt% CB. Electrical characteristics are evaluated by measuring the surface resistance using a 4-point probe. Wear characteristics are evaluated using the reciprocating wear test, and a chrome steel ball with a curvature of 6.3 mm is used as the counterpart. The results show that the addition of MWCNTs or CB can improve the electrical and wear characteristics of HIPS composites. In the case of MWCNT-HIPS composites, surface resistance, friction coefficient, and specific wear rate decrease as the concentrations of MWCNTs increase. Moreover, the addition of MWCNTs is more effective in improving the electrical and wear characteristics of HIPS composites compared to the addition of CB. To fabricate the HIPS composite with appropriate electrical and wear characteristics, more than 4 wt% MWCNTs is added to HIPS.

• 폴리머
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• 제33권3호
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• pp.203-206
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• 2009

화학적 산화중합에 의한 Polyaniline Emeraldine salt(PANI-salt)는 도펀트로 존재하는 HCl과 같은 양성 자산으로 인한 금속성 사출금형 부식이 발생한다. 본 연구에서는 비극성 유기용매인 톨루엔, 포펀트와 계면활성제 역할을 하는 dodecylbenzenesulfonic acid(DBSA)를 사용하여 유화 중합법으로 PANI-salt를 합성한 후, 공용매 toluene에서 PANI-salt와 high impact polystyrene(HIPS)를 다양한 비율로 solution-cast 혼합하여 PANI-HIPS 블렌드를 얻었다. PT-IR과 UV-Vis.로 PANI-salt 구조를 확인하였고, PANI-HIPS 블렌드의 모폴로지, 열적 및 전기적 특성을 확인하였다. PANI(50 mL)와 HIPS(1 g)을 혼합하여 사출온도 $103^{\circ}C$, 사출압력 120 psi 하에서 사출한 PANI-HIPS 사출품에서 가장 높은 전기전도도($6.02{\times}10^{-5}\;S/cm$)가 나타났다.

• 자원리싸이클링
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• 제16권5호
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• pp.57-64
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• 2007

유사비중의 범위에 있는 PVC, PET and PMMA 3종 혼합플라스틱의 마찰하전 정전선별이 2단계 분리공정을 통하여 수행되었다. PVC, PET and PMMA의 재질분리에 있어 효과적인 하전장치의 재질은 Polypropylene(PP) 과 high-impact polystyrene(HIPS) 임을 확인하였다. PP 싸이클론 하전장치를 이용한 1단계 분리공정에서, PVC의 품위와 회수율은 공기속도 10 m/s, 전기장의 세기 200 kV/m 이상, 분리대 위치 +2cm, 상대습도 30% 이하의 조건에서 각각 99.6%와 97.5%로 구하였으며, HIPS 싸이크론 하전장치를 이용한 2단계 분리공정으로부터, 공기속도 10 m/s, 전기장의 세기 250 kV/m, 분리대 위치 0cm, 상대습도 40% 이하의 조건에서 PMMA의 품위와 회수율을 각각 97.8%와 95.12%로 구하였다.

• 폴리머
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• 제35권6호
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• pp.543-547
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• 2011

전도성고분자 polyaniline(PANI)의 구조 변화없이 전기전도도를 띠면서 가공성과 기계적 특성을 증가시키는 연구를 수행하였다. 기능성 산으로 도핑된 PANI-DBSA는 유화 중합하였고, dodecylbenzenesulfonic acid(DBSA)는 계면활성제와 도펀트 역할을 동시에 하도록 하였다. 이어서 PANI-DBSA를 high impact polystyrene(HIPS)와 용액 캐스팅하여 블렌드 필름을 제조하였다. UV-vis, FTIR/ATR 분광법으로 블렌드 구조와 전기적 특성을 확인하였다. PANI-DBSA/HIPS 블렌드에 관한 연구는 분산성과 모폴로지 변화에 따른 기계적인 특성과 전기적 특성 확인에 중점을 두고 진행하였다. 전기전도도는 PANI-DBSA 함량 증가에 따라 상승하였고, 9 wt% 정도로 낮은 함량에서도 $3.5{\times}10^{-4}$ S/cm로 급격하게 상승하였다. 전도성고분자 블렌드에서 연속적인 고분자 망상구조 형성이 percolation과 전기전도도에 밀접한 연관성이 있었다.

• Advances in nano research
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• 제2권2호
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• pp.121-133
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• 2014

Polymer nanocomposites are advanced nanomaterials which exhibit dramatic improvements in various mechanical, thermal and barrier properties as compared with the neat polymer. Polystyrene/ alumina nanocomposites were prepared by an ultrasound-assisted solution casting method at filler loadings ranging from 0.2 to 2% and also at different ultrasonic frequencies, viz. 58 kHz, 192/58 kHz, 430 kHz, 470 kHz and 1 MHz. The composites were subjected to mechanical property tests (tensile and impact tests) and cavitation erosion tests to study the enhancement in functional properties. Filler dispersion in the polymer matrix was observed by SEM analysis. The effect of frequency on filler dispersion in the matrix was studied by SEM analysis and functional property enhancement of the composite material. The composites prepared at dual (high/ low) frequency (192/58 kHz) were found to show better property enhancement at low filler loadings as compared with neat polymer and also with composites prepared without ultrasound, thus reinforcing the finding that ultrasound-assisted synthesis is a promising method for the synthesis of nanocomposites.

• 한국포장학회지
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• 제28권3호
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• pp.201-210
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• 2022

Expanded polystyrene (EPS) is the most commonly used fresh food refrigeration insulation in Korea and Europe. Moreover, as the use of disposable packaging materials has increased significantly along with non-face-to-face delivery services since the COVID-19 crisis, social issues related to waste disposal are also being raised. Therefore, in this study, the life cycle of EPS boxes for fresh food is focused on the factors that have a large difference between incineration and landfill including recycling in Europe and Korea in the disposal process after use, and raw materials and energy in the manufacturing process, which account for a large portion of the environmental impact value. We tried to compare the environmental impact of evaluation. Overall, the raw material production stage, box manufacturing stage, and packaging stage have similar processes in Europe and Korea, but unlike Europe, Korea, which lacks landfills and incineration facilities, has focused on expanding the recycling rate. It was necessary to do an environmental impact assessment. Data affecting the environment were derived based on 2019 and 2020 data for Korea and 2017 and 2020 data for Europe. In order to predict the future environmental impact assessment, assumptions about the disposal rate in 2025 and 2030 were introduced and evaluated. As a result of this study, it was found that the raw material production stage of EPS boxes, which have similar processes in both Korea and Europe, has the greatest effect on the global warming effect of Korean EPS boxes. However, Korea, which has a relatively high recycling rate in the disposal process compared to incineration and landfill, showed better environmental performance than Europe in most impact indicators except freshwater eutrophication. In particular, Korea has increased the overall recycling rate compared to Europe by replacing various recyclable materials such as building materials and sundries with XPS (extruded polystyrene) recycled materials. In conclusion, it was found that increasing the recycling rate rather than incinerating and landfilling EPS boxes for fresh food in the domestic EPS industry has relatively less environmental load compared to Europe.

• 한국염색가공학회지
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• 제5권1호
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• pp.19-25
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• 1993

Plastic optical fibers(POFs) composed of poly(methylmethacrylate) (PMMA), polystyrene (PS), or polycarbonate(PC) as a core materials, and of fluorinated polymer or PMMA as a cladding were fabricated and their properties were investigated in this study. The attenuation loss of PMAA core POF was about 1,700 dB/Km at 660 nm, the loss of PS core POF was 1,800 dB/Km at 560 nm, and the loss of PC core POF was 2,200 dB/Km at 780 nm. These attenuation losses of POFs prepared ill this study were higher than those of commerically available POFs. Compared to PMMA and PS core POFs, PC core POF has excellent characteristics, including high thermal stability, high flexibility, and high impact strength.