• 제목/요약/키워드: Water-soluble Polymer

검색결과 266건 처리시간 0.032초

Quenching of Water Soluble Conjugated Polymer by Electrostatic Interaction

  • Jin, Youngeup
    • Bulletin of the Korean Chemical Society
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    • 제33권11호
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    • pp.3593-3596
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    • 2012
  • The water-soluble conjugated polymer with fluorescence quenching as a result of electrostatic interaction and aggregation was synthesized through Suzuki polymerization. The absorption and emission of anionic polymer (a-PFP) is blue shifted as compared with cationic polymer (c-PFP) although getting same backbone, and the absolute PL quantum efficiency of a-PFP in water is over 90% due to good solubility in aqueous solution. We anticipate that the fluorescence quenching of anionic and cationic polymers, with same conjugated backbone, could be shown in aqueous solution.

Enhancement of the Escherichia coli Floc Strength with Water Soluble Polymers

  • KIM, CHAN-WHA;CHOKYUN RHA
    • Journal of Microbiology and Biotechnology
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    • 제7권4호
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    • pp.282-286
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    • 1997
  • The floc strength of Escherichia coli was enhanced by adding water soluble polymer flocculants (BPA-5020 and BPA-5000) to the particulate flocculant (BPA-1000) as indicated by the increase in the shear index. The shear index of the E. coli flocs increased from 0.39 with the particulate flocculant alone to 0.94 with the particulate flocculant in conjunction with the water soluble polymer flocculant. In addition, the sedimentation rate of flocs was higher and the sedimented volume of flocs was smaller when the particulate flocculant was used with the water soluble polymer flocculant. When E. coli was flocculated first with the water soluble flocculant and the particulate flocculant was added later into the E. coli flocs formed, the sedimentation rate of the flocs was greater than that of any other combination. The shear index of the flocs was, however, independent of the sequence of the flocculant addition.

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Effects of sodium lauryl sulfate on the encapsulation of ethanol by spray-drying technique

  • Lee, Sa-Won;Kim, Chong-Kook
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 1996년도 춘계학술대회
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    • pp.288-288
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    • 1996
  • The microcapsules containing ethanol in a water-soluble polymer shell could be formed by the spray-drying technique. A mixed solution of ethanol, water and a water-soluble polymer is spray-dried at the lowest possible temperature to obtain a powder product in which the water is substantially removed and the ethanol is encapsulated in water-soluble polymer shell because of the hydrophillic property of polymer and permeability difference between ethanol and water. In this study, the effect of sodium lauryl sulfate (SLS) on the ethanol content, ethanol encapsulation efficiency and yield were investigated to maximize the microencapsulation of ethanol.

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지반함몰 긴급복구용 수용성 폴리머 파우치의 기계적 물성강화 (Mechanical Property Enhancement of Water Soluble Polymer Pouch for Ground Reinforcement)

  • 정동호;정다솜;유승경;김주헌;한중근
    • 한국지반신소재학회논문집
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    • 제16권4호
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    • pp.221-230
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    • 2017
  • 선행 연구에서 PVP를 이용하여 수용성 폴리머 파우치를 개발하였다. 그러나 개발된 재료의 용융점이 매우 낮아 재료의 성형 시 문제점이 많아 대량생산 시 필요한 성형, 제작이 불가능하였기에 성형성이 우수한 새로운 재료 조합을 이용하여 폴리머 파우치를 개발하였다. 새롭게 선정된 PEG의 수용성 변화 및 지반공동 내 보강 시 파우치의 기계적 물성을 만족해야한다. 따라서 PEG와 LLDPE, TALC 블렌딩 비율에 따른 특성평가를 실시하였는데 각 원료의 비율에 따라 발생하는 성질이 다르기 때문에 실험을 통해 적정 비율을 찾는 것이 중요하기 때문이다. 이러한 블렌딩을 통해 수용성 특성은 유지하며 인장 및 충격강도가 증진된 폴리머 파우치를 개발하였다. 최종 개발된 제품을 이용하여 직접전단 실험을 실시한 결과, 폴리머 파우치의 지반강도 효과를 확인할 수 있었다.

Novel Water-Soluble Polyfluorenes as an Interfacial layer leading to Cathodes-Independent High Performance of Organic Solar Cells

  • 오승환;심희상;박동원;정연길;이재광;문승현;김동유
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2009년도 추계학술대회 논문집
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    • pp.394-394
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    • 2009
  • Water solubility of conjugated polymers may offer many applications. Potential applications of water-soluble conjugated polymers include the polymer light-emitting diode and new materials for nano and micro hollow-capsules, and bio- or chemo-sensors. We synthesized neutral polyfluorenes containing bromo-alkyl groups by the palladium catalyzed Suzuki coupling reaction. Bromo-alkyl side groups in neutral polyfluorenes were quaternized by tri-methyl amine solution. The electrochemical and optical properties of water-soluble conjugated polymers are discussed. This novel synthesized water-soluble conjugated polymers were used as a interfacial dipole layer between active layer and metal cathode in polymer solar cell for enhancement of open-circuit voltage (Voc), which is one of the most critical factors in determining device characteristics. We also investigated the device performance of polymer solar cell with different metal cathode such as Al, Ag, Au and Cu. In polymer solar cell, novel cationic water-soluble conjugated polymers were inserted between active layer and high-work function cathode (Al, Ag, Au and Cu).

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수용성 고분자를 이용한 열화한지의 보강처리 (Strengthening Treatment of Aged Hanji with Water Soluble Polymers)

  • 김강재;이민형;엄태진
    • 펄프종이기술
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    • 제43권5호
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    • pp.1-10
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    • 2011
  • In this study, 13 water soluble polymers(6 natural polymer, 7 synthetic polymer) were treated on Hanji. Mechanical properties, morphology and oxidation index with thermal aging were measured on the aged Hanji, dewaxed Hanji and polymer treated Hanji. 3 natural polymer(such as CMC, EC, MC) and 3 synthetic polymers(such as PVA 1500, 2000, PEG 1500) treated Hanji had higher strength than other polymer treated Hanji. The oxidation index of 3% methyl cellulose solution treated Hanji did a little increase with thermal aging. Finally, methyl cellulose was found to be the most efficient method for strengthening the dewaxed Hanji. The best aging safety and thermal stability were obtained at the methyl cellulose 3% water solution.

MDF 시멘트 복합재료의 휨강도와 수분민강성에 미치는 수용성 폴리머의 영향 (The Effect of Water Soluble Polymer on the Flexural Strength and Moisture Sensitivity in MDF Cement Composites)

  • 김태현;최상흘
    • 한국세라믹학회지
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    • 제29권4호
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    • pp.298-304
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    • 1992
  • Flexural strength, microstructure, hydration reaction and moisture sensitivity in macro defect-free (MDF) cement, which basically prepared of high alumina cement (HAC) and hydroxypropyl methylcellulose (HPMC) and polyvinylalcohol (PVA) as water soluble polymer were investigated. Cement composites based on HAC-PVA system were improved in flexural strength than that of HAC-HPMC system especially, the strength of specimens added to 10 wt% of polyvinylalcohol was 160 MPa. These improvements of flexural strength were attributed to not only the effect of water soluble polymer in elimination of macropores (above 100 $\mu\textrm{m}$) and cement grain bridging, but the effect of unhydrate cement as an aggregate. Moisture sensitivity and flexural strength in wet condition of MDF cement composites immersed in water at 80$^{\circ}C$ for 3 days were decreased.

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수용성 폴리비닐알콜(PVA) 포장소재의 이용 (Review on PVA as a Water Soluble Packaging Material)

  • 이지윤;장시훈;박수일
    • 한국포장학회지
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    • 제15권1호
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    • pp.25-32
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    • 2009
  • It is now widely recognized that the disposal of packaging waste is an increasing environmental concern. Recent interest in polymer waste management of packaging materials has added incentive to the research. Poly(vinyl alcohol) is a readily biodegradable water-soluble polymer. However, this polymer cannot be processed by conventional extrusion technologies because the melting point of PVA is close to its decomposition temperature. Therefore, PVA films have been mostly prepared by solvent casting from water. Applications of PVA include sizing, binders, fibers, and films for agricultural chemicals and hospital laundry bags. A better understanding of PVA films, which also play important roles in the degradation of plastics, will expand the usage of PVA. Composite films based on PVA generally exhibit better mechanical and thermal properties than pure PVA. The aim of this review article is to review types, formation, and properties of PVA films and PVA based composite films used in packaging related researches.

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