• Polymer(Korea)
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• v.24 no.4
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• pp.538-544
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• 2000

The characteristics of cell growth and foamed cell structures of PP were investigated by a continuous foaming process. The operating parameters were the contents of blowing agent and nucleating agent, nucleating agent contents, die temperatures and die dimensions. The foaming cells grew without collapse at less than 14.5 wt% of blowing agent, isopentane. But the cells were collapsed when the blowing agent content was more than 14.5 wt%. The foam density dramatically decreased when a very small amount of the nucleating agent, 1 wt%, was added. After the nucleating agent was added, the cell's weight plummeted to one-seventh of its previous weight. Stable foam cell structures were formed at the die temperature of 17$0^{\circ}C$. However, the effects of the pressure drop rate on the cell morphology were not serious.

• Elastomers and Composites
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• v.40 no.4
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• pp.258-265
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• 2005

To study the compressive stress, recovery force and permanent strain of foams for footwear midsole, polyurethane(PU), phylon(PH) and injection phylon(IP) foams were repetitively compressed with constant compressive stress. Maximum compressive stress of PU did not decrease with repetitive compression on the constant compressive stress, but that of IP largely decreased. Engineering strain of foams were formed by repetitively compressing the three types of foam. The engineering strain of PU was smaller than that of IP and PH. Compressive stress and recovery force of IP and PH at certain strain were decreased with repetitive compression, but that of PU was not noticeably changed.

• Journal of the Korean Applied Science and Technology
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• v.16 no.2
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• pp.179-185
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• 1999

The effect of blowing agents and inner temperature on the machanical properties of the flexible polyurethane foams were investigated. In the study used that chemical blowing agents is $H_2O$ and support blowing agents. CFC-11, HCFC-114b, dichloromethane, n-penthane, iso-pentane, cyclopentane. The flexible polyurethane foams were foamed by the density of $0.015{\pm}0.002g/cm^3$ and $0.024{\pm}0.002g/cm^3$ which were used in mechanical properties measurements. Inner temperature was measure as long as the preparation of the flexible polyurethane foams of each blowing agents. The density, tensile strength, elongation, tear strength, compression strength and compression set were measured after 48 hours hardening. The result of the study was optimized dichloromethane and cyclopentane at the support blowing agents.

• Polymer(Korea)
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• v.37 no.6
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• pp.685-693
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• 2013

The foams of a poly(lactic acid) modified by the reactive compounding were produced with the batch foaming technique using supercritical $CO_2(scCO_2)$. Experiments were performed at $105{\sim}135^{\circ}C$ and 12~24 MPa. The blowing ratio and foam structure were significantly affected by changing the temperature and pressure conditions in the foaming process. The blowing ratio first increased with increasing foaming temperature and saturation pressure, reached a maximum and then decreased with a further increase in the foaming temperature and saturation pressure. Decreasing the rate of depressurization permitted a longer period of cell growth and therefore larger microcellular structures were obtained.

• Proceedings of the KAIS Fall Conference
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• 2006.11a
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• pp.324-327
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• 2006

COD 제거효율은 각 조의 부처꽃을 제외한 대조군의 경우 물상추 56%, 달뿌리풀 48%, 미나리 41%의 제거효율을 보이고, 발포유리가 첨가된 조의 경우는 물상추 69%, 달뿌리풀 68% 미나리 62%의 제거효율을 보임으로써 발포유리를 첨가한 조의 COD 제거효율이 대조군 보다 높았다. T-N의 제거효율은 발포유리를 첨가한 조의 경우 부처꽃 91%, 달뿌리풀 93%와 발포유리를 첨가한 혼합조가 94%의 높은 T-N 제거효율 보임으로써 모든 질소성분이 제거된 것으로 사료된다. T-P의 제거효율은 대조군의 부처꽃 35%, 달뿌리풀 8%이며, 발포유리를 첨가한 조의 부처꽃 78%, 달뿌리풀 43%로 발포유리를 첨가한조의 T-P 제거효율이 대조군 보다 높았다.

• Elastomers and Composites
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• v.39 no.3
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• pp.186-192
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• 2004

Compression and rebounding properties of IP(injection phylon), PH(phylon) and PU(polyurethane) foams were studied. The compression stress, rebounding stress, loss compression energy and storage compression energy of foams were decreased with increasing hardness of foams. The compression stress, loss compression energy of IP foams were lower than those of PH and PU. Rebounding stress and storage compression energy of PU foams were higher than those of IP and PH. The compression stress and rebounding of PH foam were lower than those of IP and PU.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.100-100
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• 2004

미국에서 발명된 초미세 발포기술은 기존의 발포공법과는 달리, 가스(CO2, N2)에 의해 재료에 생성된 기포(셀)의 크기가 loom이하인 작은 셀이 재료 내에 고르게 분포되도록 하여, 기존의 발포재료보다 나은 기계적 특성을 유지하도록 하였다. 그 결과, 제품의 재료비를 절감하기 위해 연구된 MCPs는 기존의 발포기술과는 달리 재료의 기계적 강도 저하를 극복하고 충격 강도와 인성의 향상을 가져왔다. 그리하여, 현재 국내의 자동차업체의 범 퍼 및 내장재로의 사용을_시작으로 산업의 다각적인 분야에 이용되고 있다.(중략)

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1976.04a
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• pp.184.3-184
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• 1976

제탁의 목적으로 맥주에 첨가한 Ppain이 숙성 도중에 어느정도 맥주의 발포성을 손상시키는가를 확인하기 위하여 발효가 끝난 처녀맥주에 30ppm의 papain을 첨가하고 $0^{\circ}C에서$ 22일동안 정치하면서 발포성을 조사해 보았다. 그 결과로써 pasteurization 과정을 밟지 않아도 30ppm의 papain은 맥주의 발포성을 현저히 손상시키는 사실이 알려졌다. 시판중의 3가지 papin 제품이 모두 같은 결과를 보였으며 papain의 농도를 5~15ppm으로 줄이면 발포성의 손실도 줄어졌다.

• 환경사랑
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• s.43
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• pp.8-9
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• 2006

환경부 비영리 사단법인으로 등록된 당 협회는 2003년 부터 시행하고 있는 생산자 책임 재활용제도의 발포합성수지(EPS, EPP, EPE 등) 재활용 사업 공제조합을 운영하고 있으며 자원의 절약과 재활용 촉진에 관한 법률 규정에 따라 발포합성수지 생산자의 재활용 의무를 대행코자 지자체 재활용 사업자 88개소와 민간 재활용 사업자 41개소를 지정 하였다.

• 환경사랑
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• s.47
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• pp.11-11
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• 2007

정부는 2003년부터 생산자책임재활용제도를 시행하고 있다. 협회는 이 제도에 따라 환경부로부터 발포합성수지 공제조합 인가를 얻어 공제조합업무를 수행하고 있다. 조합운용과 관련하여 의무생산자들의 이해를 돕기 위해 의무생산자들이 자주 물어오는 궁금한 점들을 풀어본다.