• 제목/요약/키워드: High-density polyethylene

검색결과 361건 처리시간 0.023초

Polyethylene/Ethylene Vinyl Acetate Blend의 전기전도현상 (Electrical Conduction of Polyethylene/Ethylene Vinyl Acetate Blend)

  • 이창용;김억;이미경;서광석
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1995년도 춘계학술대회 논문집
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    • pp.115-119
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    • 1995
  • Electrical conduction characteristics of Polyethylene/Ethylene vinyl acetate blends of varing vinyl acetate content(1% and 4%) were investigated at electric fields ranging from 10$\^$6/ to 10.$\^$8/ V/cm over the temperature range of 30 and 85$^{\circ}C$. It was obser-ved that the extent of current density was changed at the blends and the rate of change of current den-sity was slightly suppressed at high field range, but PE and EVA were not shown. The change of con-duction characteristics and a suppression in rate of change of current density were attributed to the VA content in PE.EVA blends.

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성형 Polyethylene의 연소성에 관한 연구 (A Study on the Combustability of Formed Polyethylene)

  • 정국삼;류영순
    • 한국안전학회지
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    • 제9권3호
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    • pp.60-66
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    • 1994
  • The purpose of this study is to compare the combustability of the formed high density polyethylene (HDPE) with the low density polyethlyene(LDPE). That is, the easiness of ignition is examined by using the methods with Oxygen Index(OI) Tester and ventilation parameter, and the combustion velocity of these polyethylenes is measured by changing the size and shape of opening area. As the result of it, the oxygen index of HDPE, in a ignition, is required more than LDPE. Then, the concentration distribution of CO by combustion is increased when the opening area is small, but, in the same opening area, LDPE tends to increase more than HDPE. In addition, as the ratio of height to width of opening area is increased, combustion velocity becomes faster relatively. In consequence, when it is generally considered, the combustability of LDPE is better than HDPE.

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Polyethylene flow prediction with a differential multi-mode Pom-Pom model

  • Rutgers, R.P.G.;Clemeur, N.;Debbaut, B.
    • Korea-Australia Rheology Journal
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    • 제14권1호
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    • pp.25-32
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    • 2002
  • We report the first steps of a collaborative project between the University of Queensland, Polyflow, Michelin, SK Chemicals, and RMIT University, on simulation, validation and application of a recently introduced constitutive model designed to describe branched polymers. Whereas much progress has been made on predicting the complex flow behaviour of many - in particular linear - polymers, it sometimes appears difficult to predict simultaneously shear thinning and extensional strain hardening behaviour using traditional constitutive models. Recently a new viscoelastic model based on molecular topology, was proposed by McLeish and carson (1998). We explore the predictive power of a differential multi-mode version of the porn-pom model for the flow behaviour of two commercial polymer melts: a (long-chain branched) low-density polyethylene (LDPE) and a (linear) high-density polyethylene (HDPE). The model responses are compared to elongational recovery experiments published by Langouche and Debbaut (19c99), and start-up of simple shear flow, stress relaxation after simple and reverse step strain experiments carried out in our laboratory.

Optimization of the Processing Parameters for Green Banana Chips and Packaging within Polyethylene Bags

  • Mitra, Pranabendu;Kim, Eun-Mi;Chang, Kyu-Seob
    • Food Science and Biotechnology
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    • 제16권6호
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    • pp.889-893
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    • 2007
  • The demand of quality green banana chips is increasing in the world snacks market, therefore, the preparation of quality chips and their subsequent shelf life in packaging were evaluated in this study. Banana slices were fried in hot oil to the desired moisture content (2-3%) and oil content (40%) in chips at 3 different temperatures, and the impact of different pretreatments were compared by sensory assessment. A linear relationship between time and temperature was used to achieve the optimal processing conditions. Banana slices fried at the lower temperature of $145^{\circ}C$ took longer to reach the desired chip qualities, but gave the best results in terms of color and texture. Blanching was the most effective pre-treatment for retaining the light yellow color in finished chips. For extending the shelf life of chips, moisture proof packaging in double layer high density polyethylene was more effective than single layer low density polyethylene.

트리 억제제 첨가에 의한 저밀도 폴리에틸렌의 내방사선성 향상 (The Improvement of Radiation Characteristics of Low Density Polyethylene by Addition of Treeing Inhibitors)

  • 김기엽;이청;류부형;임기조
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제49권8호
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    • pp.455-461
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    • 2000
  • The inhibiting effects of electrical treeing and insulation properties of LDPE contained with treeing inhibitors was studied under radiation environment. Barbituric acid and its derivatives were selected as treeing inhibitors. The inception voltage and growth of tree, AC breakdown strength, volume resistivity, high frequency capacitance, and dissipation factor were observed as a function of dose(up to 1000 kGy). And also, measurements of thermo-luminescence(TL), and gel content were carried out. Crosslinked low density polyethylene(XLPE) contained with treeing inhibitors shows better insulation characteristics such as electrical tree propagation, AC breakdown strength, and volume resistivity than those of pure LDPE. The most effective treeing inhibitor was found on the barbituric acid contained XLPE.

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EFFECT OF ARGON AND OXYGEN PLASMAS ON VARIOUS POLYETHYLENE SHEETS

  • Chen, Yashao;Hirayama, Naoki;Gomi, Masaki;Kiuchi, Kenji;Momose, Yoshihiro
    • 한국표면공학회지
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    • 제32권3호
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    • pp.344-350
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    • 1999
  • The surface chemical structure of three kinds of polyethylene (PE): high density (HD) PE, low density (LD) PE and linear (L)-LDPE exposed to Ar and $O_2$ plasmas has been investigated using XPS. Oxygen was incorporated in a more increased amount for HDPE than for L-LDPE and LDPE. Ar plasma tended to incorporate more oxygen than $O_2$ plasma. The XPS valence band spectra for Ar plasma exhibited a clear peak assigned to $O_2$s character. By chemical derivatization method it was found that the amount of -COOH group at the surface was much greater than that of -OH group. The hydrophilic nature of plasma-treated PE increased in the order: LDPE

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Electroflocking을 이용한 단섬유 프리프레그 제조에 관한 연구 (Manufacture of Short Fiber Prepreg using Electroflocking)

  • 임순호;이상수;박민;김준경;최철림;권성진
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2002년도 추계학술발표대회 논문집
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    • pp.288-291
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    • 2002
  • The carbon fiber or glass fiber reinforced prepregs were manufactured using electrostatic flocking technology. The powder of high density polyethylene was used as a matrix. The base film of polyethylene was prepared using a fluidized bed of polyethylene powder under the high electric field. We obtained HDPE film with uniform thickness of minimum $80\mu\textrm{m}$. And the fibers were aligned on the molten HDPE film by the electroflocking process. The short fibers with 1mm were easily electrically charged and aligned under the high electric field. The carbon fibers with high conductivity were elasily electrically charged than the glass fibers with low conductivity. So lower electric field was needed for the carbon fibers.

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반응 용융 가공에 의한 고밀도 폴리에틸렌의 가교 특성 연구 (Crosslinking Characteristics of High Density Polyethylene by Reactive Melt Processing)

  • 이종록;이동근;홍순만;강호종
    • 폴리머
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    • 제29권4호
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    • pp.385-391
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    • 2005
  • 고밀도 폴리에틸렌(HDPE)에 과산화물 가교제인 dicummyl pe개xide(DCP)와 peroxide(PBP)를 각각 첨가하여 반응 용융 가공 조건이 HDPE의 가교 특성에 미치는 영향을 살펴보았다. 용융 가공 시 가교제 첨가에 따라 가교에 의한 용융점도 증가에 의하여 믹서의 토크가 증가하는 것으로 보아 반응 용융 가공에 의한 가교 HDPE가 형성됨을 확인할 수 있었으며 그 결과, HDPE의 용융점도는 증가하며 밀도 및 용융온도 그리고 용융엔탈피의 감소가 초래됨을 알 수 있었다. 가교 HDPE는 HDPE에 비하여 강도가 우수한 반면 상대적으로 낮은 신율을 보이며 이러한 현상은 가교제로 PBP를 사용했을 경우 더 두드러짐을 확인하였다. 가교 HDPE의 기계적 물성은 반응 가교온도 $150^{circ}C$에서 가장 높음을 알 수 있는 반면 반응 가공시간에는 큰 영향을 받지 않음을 확인하였다.

Effect of Metallocene-catalyzed Polyethylene on the Rheological and Mechanical Properties of Poly(phenylene sulfide)/Polyethylene Blends

  • Lee, Bo-Sun;Chun, Byoung-Chul;Chung, Yong-Chan
    • Fibers and Polymers
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    • 제5권2호
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    • pp.145-150
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    • 2004
  • Blends of poly(phenylene sulfide) (PPS) and polyethylene, either linear low density polyethylene (LLDPE) or metallocene-catalyzed polyethylene (MPE), that were prepared by melt blending, were investigated. From the rheological properties as determined by capillary rheometry, the melt viscosity of both PPS/LLDPE and PPS/MPE blends was low when PE was in dispersed phase, but high melt viscosity was observed for both blends with PPS in dispersed phase. Significant differences depending on the composition were found in the mechanical properties such as percent elongation at break and notched Izod impact strength. In addition, dispersed phase morphology of the blends was analyzed by a scanning electron microscope (SEM), together with brief discussion about the difference between them.

용액법에 의해 작성한 고밀도 폴리에틸렌 박막의 절연파괴(絶緣破壞)특성 연구 (The Electric Breakdown Characteristic of High Density Polyethylene by Making Use of Solution-grown Thin Films)

  • 김석기;이한우;한상옥;박강식;박귀만;김종석
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1994년도 하계학술대회 논문집 C
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    • pp.1379-1381
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    • 1994
  • In order to investigate the effects of crystal structure in electrical breakdown of polyethylene film. Low molecular materials in polyethylene are removed by the method as follow. Polyethylene was dissolved in xylene and filtered through a glass fiber filter. And then, a polyethylene thin films of thickness $0.5 - 0.9{\mu}m$ are prepared with heat treatment from solution casting. To evaluate the performance of PE film, Electrical breakdown of PE film are measured on M( Al) - I (PE)-M(Al) system.

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