• 소성∙가공
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• 제11권8호
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• pp.651-667
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• 2002

Overview of plastics processing is described and the research trend of the processing is also noted. The main manufacturing processes in the plastics industry are injection molding, blow molding, compression molding, transfer molding, extrusion and thermoforming. The principles of those processes have been discussed and molds for shaping operation have been mentioned. References for each process have also been presented.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.399-400
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• 2006

M390 microclean(R) of $B{\ddot{o}}hler$ Edelstahl is a powder metallurgical plastic mould steel with a high level of corrosion and wear resistance and therefore often used in the plastics processing industry. But as a consequence of rapidly advancing developments in the plastics processing industry the required level of wear resistance of tool steels in this field is constantly rising. For that reason a new PM tool steel with higher hardness values and an increased amount of primary carbides has been developed to improve the resistance against abrasive and adhesive wear. The wear resistance of both steels against adhesive situations for components of the plastification unit of injection moulding machines has been tested with a novel method. In case of processing polyolefins with an injection moulding machine it was found that there is adhesive wear between the check-ring and the flights of the screw tip of the non-return valve under certain circumstances. The temperature in that region was measured with an infrared temperature sensor. The existence of significant peaks of that signal was used as an indicator for an adhesive wear situation.

• Journal of the Korean Wood Science and Technology
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• 제42권5호
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• pp.499-509
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• 2014

Wood filler is a porous and anisotropic material having different size, shape, and aspect ratio. The use of wood fillers such as wood particle, wood flour, and wood pulp in wood plastic composites (WPCs) are growing rapidly because these wood fillers give improved strength and stiffness to WPCs. However, the wood fillers have originally poor compatibility with plastic matrix affecting the mechanical properties of WPCs. Therefore, to improve compatibility between wood and plastic, numbers of physical and chemical treatments were investigated. While the various treatments led to improved performances in WPC industries using petroleum-based plastics, full biodegradation is still issues due to increased environmental concerns. Hence, bio-based plastics such as polylactide and polyhydroxybutyrate having biodegradable characteristics are being applied to WPCs, but relatively expensive prices of existing bio-based plastics prevent further uses. As conventional processing methods, extrusion, injection, and compression moldings have been used in WPC industries, but to apply WPCs to engineered or structural places, new processing methods should be developed. As one system, co-extrusion technique was introduced to WPCs and the co-extruded WPCs having core-shell structures make the extended applications of WPCs possible.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.1828-1833
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• 2003

In a foaming process of microcellular plastics (MCPs) with a batch process, amorphous plastics and crystalline plastics have different characteristics for a foaming temperature. It is known that a foaming of amorphous plastics occurs at the temperature above a glass transition temperature, however, it is discovered that crystalline plastics do not take place above a glass transition temperature without exception, and even though the foaming occurs, it does not in all the range. In this research, to measure foaming temperature of crystalline polymer, a foaming experiment was performed using one of the typical crystalline polymer, polypropylene. To analyze whether the foaming occurs both at amorphous and crystalline fields, SEM was applied

• 한국식품과학회지
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• 제40권4호
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• pp.365-374
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• 2008

환경문제가 대두되면서 이미 선진국의 포장재 공급업체들은 소비자의 관심과 재활용 규제가 친환경 포장재 수요를 불러일으킬 것으로 전망하였다. 이러한 수요에 대응하기 위해 옥수수와 같은 식물을 활용해 만든 여러 형태의 바이오 플라스틱을 출시해 왔으며, 국내 업체들에서도 점차 이에 대한 관심을 높여가고 있다. 점차 강화되고 있는 폐기물 부담금과 불안정한 국제 유가를 고려할 때, 바이오 플라스틱은 소비자들의 친환경 제품에 대한 관심과 연결되어 국내 플라스틱 산업의 새로운 활로가 될 것으로 기대된다. 이를 위해서는 비교적 초기단계에 있는 국내 친환경 플라스틱 기술에 대해 기업과 대학에서 활발한 연구가 이루어져야 할 것으로 보인다. 빠르면 2-3년 내에 생분해성 플라스틱을 주원료로 한 도시락 용기, 컵라면 용기 및 각종 상품용 포장용기가 실용화되고, 장기적으로는 폐수내의 중금속 이온 제거제를 비롯하여 생체 의료용제 등과 같은 첨단의 고부가 생명 공학기술을 응용한 다양한 종류의 환경 친화 제품의 출시가 예상되며, 향후 생분해성 플라스틱 산업은 시장 잠재력과 성장성이 무한한 환경 관련 사업으로 평가된다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집C
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• pp.263-268
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• 2001

MCPs means Micro Cellular Plastics. The micro-cells are generated in the products by the difference of dissolution through the pressure drop after super critical fluid of CO2 or N2 dissolves into polymer. We have developed injection molding process adopting MCPs and applied it to a broad range of injection molded thermoplastic materials and applications. It can prevent the leakage of impact strength and increase the thermal conductivity, moreover regulate the thermal conductivity. Then we can develop the high strength foaming plastics. Also, it can be gained a competitive advantage by utilizing its processing benefits, e.g. the lightweight products and significant reductions in material consumption.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1406-1409
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• 2003

There is a great demand for reducing the amount of material used in mass-produced plastics parts, for material cost constitutes a large percentage of the total cost of 60%. It may be noted that the price of plastics is directly rotated to the price of petroleum. Material reduction therefore decreases the amount of oil needed for the manufacture of plastics and thus help conserve this natural resource. Therefore microcellular foaming process(MCPs) was studied for solving this problems alternatively in 1980's at M.I.T Until now in MCPs carbon dioxide gas was mainly used for microcellular foaming. Besides, Talc was used for reducing the price of plastics. Consequently, we must certificate using the Talc in MCPs according to contents of the Talc.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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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.

• 자원리싸이클링
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• 제6권2호
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• pp.12-21
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• 1997

Plastics waste constitutes approximately 23% by volume of the municipal solid waste(MSW) generated in the U.S. each year, and have slow rate of degradation in the environment. Therefore, there is a great deal of public pressure to recycle plastics, and more than 100 million people participate in the curbside recycling programs. Despite the high level of public interest, only 3.5% of the plastic are recycled, which is substantially lower than the recycle rates of other materials such as paper fibers, glass, and iron. Although a large part of the reason is due to the low price of virgin polymers, which in turn is due to the low price of oil, it is possible to make the plastics recycling as a profitable business by developing advanced technologies. In this communication, various methods of separating pplastics from metals and from each other are discussed.

• 한국레이저가공학회:학술대회논문집
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• 한국레이저가공학회 2002년도 춘계학술발표대회 논문개요집
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• pp.12-16
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• 2002