• 한국공작기계학회논문집
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• 제15권1호
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• pp.39-48
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• 2006

In this paper, polymer composites based sandwich structures like beams and plates are optimised by using parametric study. The structures are composed of fibre reinforced composites for facial material and resin concrete and PVC foam for core materials. The stacking sequences and thickness of the composites are controlled as major parameters to find out the optimal condition for machine tool components. For the plate structure of machine tool bed composites-skined sandwich structure which has several ribs are proposed to enhance bending stiffnesses in two major directions at the same time. Dynamic robustness of a machine tool structure is investigated using modal analysis. From the results optimal configuration and materials for high precesion machine tools are proposed. And the plate was made of fiber reforced composite material and PVC foam.

• 멤브레인
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• 제18권2호
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• pp.132-137
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• 2008

폴리비닐리덴플로라이드(PVDF) 지지체 위에 빗살모양의 술폰화된 공중합체를 코팅하여 나노 분리막을 제조하였다. 빗살모양의 공중합체는 원자전달 라디칼 중합법(ATRP)에 의해 제조하였으며, 폴리비닐클로라이드의 주사슬과 폴리스티렌 술폰산(PSSA)의 곁사슬로 구성되어 있다. 핵자기 공명법($^1H$-NMR), FT-IR분광학 그리고 WAXS 분석법에 의해 공중합체가 성공적으로 합성되었음을 확인하였다 PVC-g-PSSA로 구성된 복합 나노 분리막은 PSSA의 함량이 증가함에 따라 플럭스와 배제율 모두 증가하였다. 이러한 성능 향상은 분리막의 술폰산의 함량의 증가로써 설명할 수 있다. PSSA가 71wt%첨가된 나노 복합막의 배제율은 $Na_2SO_4$ 88%, NaCl 33%을 나타내었고, 플럭스는 $Na_2SO_4$ 26, NaCl $34L/m^2 h$을 각각 나타내었다.

• Composites Research
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• 제17권6호
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• pp.28-36
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• 2004

복합재료의 성형조건과 재료의 변형간의 관계를 규명하기 위해 PVC 포움-직물 복합재료 샌드위치 구조의 성형공정 중 토우 구조의 미소 변형을 고찰하였다. 실험에 사용한 포움은 4가지 밀도를 가지는 PVC 포움이며, 면재로는 탄소섬유게폭시 프리프레그(3k)를 사용하였다. 디지털 현미경과 이미지 분석 도구를 사용하여 직물 복합재료의 굴곡 각과 토우 진폭 등의 토우 파라메터를 측정하여 서로 비교하였다. 성형 중 포움의 변화가 직물 복합재료 구조의 변형에 미치는 영향을 파악하기 위해 세 가지 온도 조건($25^{\circ}C$, $80{\circ}C$, $125^{\circ}C$)에서 포움의 압축 실험을 수행하였다. 복합재료 토우 구조의 현미경 관찰 결과 토우의 미소 변형은 포움의 밀도와 성형 압력에 따라 서로 다른 경향을 나타내었으며. 특히 포움의 변형 거동에 큰 영향을 받는 것을 확인하였다.

• 대한화학회지
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• 제29권3호
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• pp.319-327
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• 1985

충진제의 함량, titanate계 coupling agent의 종류, 처리량에 따른 PVC-Ni 복합재의 전기적.기계적 성질을 연구하였다. coupling agents처리에 의해 충진제의 분산상태가 양호해지고, 충진제 표면의 불순물이 대체되어 복합재의 전기저항은 감소되며 기계적 성질을 연구하였다. coupling agent처리에 의해 충진제의 분산상태가 양호해지고, 충진제 표면의 불순물이 대체되어 복합재의 전기저항은 감소되며 기계적 성질들은 향상되나 과량의 coupling agent의 처리는 이들 효과를 상쇄함을 보였다.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2004년도 춘계학술대회
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• pp.219-231
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• 2004

The Charpy and Izod impact tests are the most prevalent techniques used to characterize the effects of high impulse loads on polymeric materials. An analysis method for rubber toughened PVC is suggested to evaluated critical dynamic strain energy release rates(G$_c$) from the Charpy impact tester was used to extract ancillary information concerning fracture parameters in additional to total fracture energies and maximum critical loads. The dynamic stress intensity factor KID was computed for varying amounts of rubber contents from the obtain maximum critical loads and also toughening effects were investigated as well. The fracture surfaces produced under low velocity impact for PVC/MBS composites were investigated by SEM. The results show that MBS rubber is very effective reinforcement material for toughening PVC.

• Steel and Composite Structures
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• 제47권6호
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• pp.781-794
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• 2023

In order to directly apply seawater and sea sand in construction without desalination, a type of square concrete-filled steel tube (CFST) encased with prefabricated seawater sea-sand concrete filled Polyvinyl Chloride (PVC)/Glass Fiber Reinforced Polymer (GFRP) tube column was proposed. Twenty short columns were tested under uniaxial loads, and the test parameters included inner tube types, seawater sea-sand concrete replacement ratios, concrete strength, the wrapping area of Carbon Fiber Reinforced Polymer (CFRP) strips and the thickness of GFRP tube. The effects of the parameters on failure modes, loading capacity, ductility and strain responses were discussed. All the tested specimens failed with serious buckling of the steel tubes and fracture of the inner tubes. The specimens had good residual bearing capacity corresponding to 64% to 88.9% of the peak capacity. The inner GFRP tubes and PVC tubes wrapped by CFRP strips provided stronger confinement to the core concrete, and were good choices for the proposed columns. Moreover, an analytical model for the composite column with different inner tube types was proposed.

• 한국지반신소재학회논문집
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• 제5권2호
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• pp.39-44
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• 2006

복합 라이너 시스템에서 차수막으로서 PVC 지오멤브레인을 사용하기 위해서는 PVC 지오멤브레인의 침출수내의 화학성분에 대한 화학적 적합성이 중요한 요소이다. 본 논문에서는 0.76mm 두께의 PVC 지오멤브레인이 갖는 합성 일반도시 폐기물 침출수와의 적합성을 실내실험을 통해 살펴보았다. $23^{\circ}C$와 $50^{\circ}C$ 두 가지 경우에 대해 각각 30일, 60일, 90일, 120일 동안 합성 침출수에 PVC 지오멤브레인을 노출시켜 외적형태와 물리적, 역학적 성질의 변화를 측정하였다. 비록 약간의 실험오차와 멤브레인 자체의 불균일성이 존재하지만, 합성된 침출수는 실험에 사용된 PVC 지오멤브레인의 물리적, 역학적 성질을 크게 변화시키지 않았다.

• 복합신소재구조학회 논문집
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• 제6권4호
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• pp.16-23
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• 2015

The industrialization and urbanization forced to increase the density of pipelines such as water supply, sewers, and gas pipelines. The materials used for the existing pipe lines are mostly composed of concretes and steels, but it is true that the development for more durable and efficient materials has been continued performed to produce long lasting pipe lines. Recently, underground pipes serve in diverse applications such as sewer lines, drain lines, water mains, gas lines, telephone and electrical conduits, culverts, oil lines, etc. In this paper, we present the result of investigation pertaining to the structural behavior of unplasticized polyvinyl chloride (PVC-U) flexible pipes buried underground. In the investigation of structural behavior such as a ring deflection, pipe stiffness, 4-point bending test, experimental and analytical studies are conducted. In addition, pipe stiffness is determined by the parallel plate loading tests and the finite element analysis. The difference between test and analysis is about 8% although there are significant variations in the mechanical properties of the pipe material. In addition, it was found by the 4-point bending test there is no problem in the connection between the pipes by coupler.

• Bulletin of the Korean Chemical Society
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• 제29권6호
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• pp.1121-1124
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• 2008

A carbon composite was synthesized by mechanical mixing of ball-milled graphite and PVC powders, followed by pyrolysis reaction of PVC. Natural graphite ball milled under atmosphere of argon or air leads to a disordered structure. It appears that the electrochemical lithium intercalation reaction is dependent on the atmosphere in which the graphite is ball milled. The carbon composite obtained using air-milled graphite shows a high reversible capacity and high initial coulombic efficiency compared to argon-milled graphite. This is attributed to the enhanced thermal stability of a disordered structure in the air milled sample. For the one with air-milled graphite, the disordered structure is maintained during heat treatment, while argon-milled graphite is partially crystallized.

• Bulletin of the Korean Chemical Society
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• 제28권3호
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• pp.439-442
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• 2007

A solid state Hg(Au)/HgO reference electrode was prepared utilizing gold amalgam solid particles. Solid fine powder of the gold amalgam was prepared by chemical reduction of Au(III) with NaBH4 followed by reduction of Hg(II) in the presence of gold fine particles. The solid content in the suspension of the gold amalgam particles and fine mercury oxide particles in DMF containing PVC was precipitated by the addition of a large amount of water to give solid Hg(Au)/HgO/PVC mixture. After drying, the mixture was pressure-molded to a physically stable Hg(Au)/HgO composite reference electrode material. The electrochemical characteristics of the electrode as a reference electrode were very similar to an ordinary Hg/HgO reference electrode. The electrode material can be molded and fabricated in any desired shape and size. The surface can be renewed by a simple polishing process whenever contaminated or deactivated. The applicability of the electrode in the electrochemical detection of carbohydrates after anion exchange separation was evaluated.