• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.5
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• pp.816-822
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• 2001

The thermoforming process is widely used in the plastics industry to produce articles for the packaging, automotive, domestic construction and leisure industries. The microcellular foaming process appeared at M.I.T. in 1980s to save a quantity of polymer materials and increase their mechanical properties. The glass transition temperature of polymer materials is one of many important process variables in appling the microcellular foaming process to the conventional thermoforming process. The goal of this research is to evaluate the relation between gas absorption and glass transition temperature in batch process using microcellular foaming process. The weight gain ratio of polymer materials has a conception of gas absorption. Polymers such as acrylonitrile-butadiene-styrene(ABS), polystyrene(PS) have been used in this experiment. According to conventional Chows model and Cha-Yoon model, it was estimated with real experimental result to predict a change of glass transition temperature as a function of the weight gain ratio of polymer materials in batch process to gain microcellular foamed plastic products.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1420-1423
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• 2005

Micro Cellular Plastics create a sensation at polymer industrial for lowering product cost & overcoming a lowering of mechanical intensity. Reduction of MCPs cell size increases the intensity of MCPs. This research based on the experiment about cell size reduction method. At this study, Quenching & Pressure foaming process are introduced to one of methods. Conclusion of study is that Quenching process is the simplest process for nano cell formation.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1366-1369
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• 2003

Today, the industries use polymer material for many purpose. Specially, it is important in automobile industry because tile costs of polymer hold high proportion of the overall cost. If we reduce the weight of automobile, fuel efficiency of car is raised and cost of bumper is lower. Therefore there are many efforts to reduce of car currently. The purpose of this paper is to reduce polymer used in car bumper.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.896-899
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• 2002

Microcellular foaming Process has several merits, impact strength elevation, thermal insulation, noise insulation, and raw material saving etc. This method make the glass transition temperature of polymers low, and diminish the residual stress of polymers. This characteristics of Microcellular foaming process influences the physical properties of recycled polymers. This paper describes about the impact strength change of Microcellular foamed recycled ABS.

• Proceedings of the KSME Conference
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• 2003.11a
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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