• Title/Summary/Keyword: Polyvinyl alcohol

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Preparation of melamine-formaldehyde microcapsule by surfactants (안정화제에 따른 멜라민-포름알데히드 마이크로캡슐의 제조)

  • Oh, Seong-Dae;Choi, Seong-Ho;Lee, Se-Hee;Lee, Kwang-Pill;Kim, Sang-Ho
    • Analytical Science and Technology
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    • v.18 no.2
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    • pp.97-103
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    • 2005
  • The various size and morphology microcapsules were prepared to produce smell sweet by heating condensation reaction of melamine and formaldehyde using 5-types of surfactants such as the laurylbenzenesulfonic acid sodium salt (SDS), polyvinylpyrrolidon (PVP), polyvinyl alcohol (PVA), Span-80 and 2-acrylamido-2-methyl-1-1 propanesulfonic acid (AMP). As result it was found that the size and morphology of microcapsule is intimately associated with a kind of surfactants. In order to prepare microcapsule with antibacterial, the silver nanoparticle was prepared by gamma-irradiation. microcapsule with silver nanoparticle was prepared.

Algicidal Effect of Immobilized Bacteria against S. hantzschii in Microcosm (살조세균 Pseudomonas fluorescens HYK0210-SK09의 두 가지 담체 포집능과 이를 이용한 microcosm에서 Stephanodiscus hantzschii (Bacillariophyceae)의 살조능 연구)

  • Jung, Seung-Won;Kim, Young-Ok;Han, Myung-Soo
    • Korean Journal of Environmental Biology
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    • v.27 no.3
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    • pp.244-251
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    • 2009
  • To assess the algicidal effect of a bacterium, Pseudomonas fluorescens HYK0210-SK09 (SK09), attached to activated carbon polyvinyl alcohol (ACPA) and cellulose sponge (CS) carriers against Stephanodiscus hantzschii, the present study was carried out in an indoor-microcosm. As comparing immobilization effects of two carriers, the ACPA carrier allowed for higher packing cell density of SK09 compared to the CS carrier. In the microcosm, immobilized SK09 cells were applied to control S. hantzschii blooms. Immobilized SK09 cells exhibited a species-specific activity towards the diatom, showing an algicidal effect up to 72% attached by ACPA carriers and to 51% attached by CS carriers. In particular, a level of conductivity treated with ACPA carriers was decreased than that of CS carriers. The present study clearly demonstrates that ACPA-immobilized SK09 cells could effectively control S. hantzschii blooms and improve water quality in the microcosm ecosystem.

Effect of Polyvinyl Alcohol Fiber Volume Fraction on Pullout Behavior of Structural Synthetic Fiber in Hybrid Fiber Reinforced Cement Composites (하이브리드 섬유 보강 시멘트 복합 재료에서 구조용 합성 섬유의 인발 거동에 미치는 폴리비닐 알코올 섬유 혼입률의 효과)

  • Lee, Jin-Hyung;Park, Chan-Gi
    • Journal of the Korea Concrete Institute
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    • v.23 no.4
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    • pp.461-469
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    • 2011
  • In this study, the effect of polyvinyl alcohol (PVA) fiber volume fraction on the pullout behavior of structural synthetic fiber in hybrid structural synthetic fiber and PVA fiber cement composites are presented. Pullout behavior of the hybrid fiber cement composites and structural synthetic fiber were determined by dog-bone bond tests. Test results found that the addition of PVA fiber can effectively enhance the structural synthetic fiber cement based composites pullout behavior, especially in fiber interface toughness. Pullout test results of the structural synthetic fiber showed the interface toughness between structural synthetic fiber and PVA fiber reinforced cement composites increases with the volume fraction of PVA fiber. The microstructural observation confirms the incorporation of PVA fiber can effectively enhance the interface toughness mechanism of structural synthetic fiber and PVA fiber reinforced cement composites.

Polyvinyl Alcohol Degradation by Microbacterium barkeri KCCM 10507 and Paenibacillus amylolyticus KCCM 10508 in Dyeing Wastewater

  • Choi, Kwang-Keun;Park, Chul-Hwan;Kim, Sang-Yong;Lyoo, Won-Seok;Lee, Sang-Hun;Lee, Jin-Won
    • Journal of Microbiology and Biotechnology
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    • v.14 no.5
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    • pp.1009-1013
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    • 2004
  • The purpose of this study was to investigate the degradation of PVA (polyvinyl alcohol) contained in dyeing wastewater by a mixed culture of Microbacterium barkeri KCCM 10507 and Paenibacillus amylolyticus KCCM 10508. Firstly, synthetic wastewater which contained different initial concentrations of PVA varying from 50 to 3,500 mg/l were tested to obtain optimal PVA biodegradation activity of isolated strains, and the above two strains were found to degrade PVA up to 90%, when the initial concentration of PVA was 750 mg/l and below. Next, dyeing wastewater was tested by a nixed culture of the two isolated strains, and 42% and 55% of the initial concentrations of PVA and COD, respectively, was removed after five days. MLSS was gradually increased from an initial 1,400 to 2,500 mg/l, and the pH was also increased from 5.1 to 7.8. Sterilized dyeing wastewater was tested to find the effect of strains only on the biodegradation of PVA, and PVA degradation ratio and COD removal ratio were 50% and 72.8%, respectively. Thus, the results indicated that these two strains have good ability to degrade PVA and remove COD in dyeing wastewater, Finally, it is expected that if these two strains were used in the dyeing wastewater treatment, good efficiency for PVA degradation and COD removal could be achieved.

Immobilization of Layered Double Hydroxide into Polyvinyl Alcohol/Alginate Hydrogel Beads for Phosphate Removal

  • Han, Yong-Un;Lee, Chang-Gu;Park, Jeong-Ann;Kang, Jin-Kyu;Lee, In;Kim, Song-Bae
    • Environmental Engineering Research
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    • v.17 no.3
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    • pp.133-138
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    • 2012
  • Polyvinyl alcohol/alginate hydrogel beads containing Mg-Al layered double hydroxide (LDH-PVA/alginate beads) were synthesized for phosphate removal. Results showed that blending PVA with the LDH-alginate beads significantly improved their stability in a phosphate solution. The kinetic reaction in LDH-PVA/alginate beads reached equilibrium at 12 hr-post reaction with 99.2% removal. The amount of phosphate removed at equilibrium ($q_e$) was determined to be 0.389 mgP/g. The equilibrium data were described well by the Freundlich isotherm with the distribution coefficient ($K_F$, 0.638) and the constant (n, 0.396). Phosphate removal in LDH-PVA/alginate beads was not sensitive to solution pH. Also, the removal capacity of LDH-PVA/alginate beads ($q_e$, 1.543 mgP/g) was two orders of magnitude greater than that of PVA/alginate beads ($q_e$, 0.016 mgP/g) in column experiments. This study demonstrates that LDH-PVA/alginate beads with a higher chemical stability against phosphate compared to LDH-alginate beads have the potential for phosphate removal as adsorptive media.

Characteristics of Nickel Aluminate Ceramics Synthesized by Organic (PVA)-Inorganic Solution Technique (PVA 폴리머를 이용한 니켈 알루미네이트 분말의 합성 및 특성연구)

  • 이상진;김주원
    • Journal of the Korean Ceramic Society
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    • v.40 no.7
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    • pp.690-695
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    • 2003
  • Soft-solution route employing PVA(Polyvinyl Alcohol) as a polymeric carrier in a mixed metal cation solution was used for synthesis of single-phase nickel aluminate (NiA1$_2$O$_4$) powders. The PVA ensured the homogeneous distribution of metal ions in the solution and it resulted in the decrease of crystallization temperature. The synthesized powders prepared by PVA addition were soft and ball-milled easily. The ball-milled powders of about 300 nm in size were fully densified to density of 4.35 g/㎤ at 1600$^{\circ}C$ for 1 h. The Vickers hardness, flexural strength, fracture toughness and thermal expansion coefficient of the sintered nickel aluminate were 14.2 ㎬, 304 ㎫, 4.8 ㎫$.$m$\^$1/2/ and 9.8${\times}$10$\^$-6//$^{\circ}C$, respectively.

Preparation of Gel Polymer Electrolyte Membranes of Polyvinyl Alcohol and Poly (acrylic acid) for Zn Air Batteries (아연공기전지를 위한 Polyvinyl Alcohol과 Poly (acrylic acid)의 블랜드를 이용한 겔 고분자 전해질막의 제조)

  • Kim, Chanhoon;Koo, Ja-Kyung
    • Membrane Journal
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    • v.22 no.3
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    • pp.208-215
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    • 2012
  • Gel polymer electrolyte membranes were prepared from blends of polyvinyl alcohol (PVA) and poly (acrylic acid) (PAA), by solution-cast technique. The PAA content in the blend varied from 30 to 80 wt%. With the gel polymer electrolyte membranes, Zn air batteries were fabricated. The gel polymer electrolyte membranes were characterized by means of stress-strain test, impedance test. The Zn air batteries were tested by current interrupt method and galvanostatic discharge method. The tensile strength and tensile modulus decreased with increasing PAA content in the gel polymer electrolyte membrane. On the other hand, the ionic conductivity increased with increasing PAA content. The effect of ionic conductivity trend of the gel polymer electrolyte membrane in the Zn air battery was confirmed through current interrupt method and galvanostatic discharge method experiments. The battery with higher PAA content gel polymer electrolyte membrane showed lower IR drop and higher discharge capacity.