• 한국섬유공학회:학술대회논문집
• /
• 한국섬유공학회 2003년도 봄 학술발표회 논문집
• /
• pp.48-51
• /
• 2003

Poly(vinyl alcohol) (PVA) obtained by the saponification of poly(vinyl ester) like poly(vinyl acetate) or poly(vinyl pivalate) is a linen. semicrystalline polymer, which have been widely used as fibers for clothes and industries, films, membranes, medicines for drug delivery system, and cancer cell-killing embolic materials[1-3]. PVA fibers and films have high tensile and compressive strengths, high tensile modulus, and good abrasion resistance due to its highest crystalline lattice modulus. (omitted)

• 한국섬유공학회:학술대회논문집
• /
• 한국섬유공학회 2003년도 가을 학술발표회 논문집
• /
• pp.104-107
• /
• 2003

Poly(vinyl alcohol) (PVA) obtained by the saponification of poly(vinyl ester) like poly(vinyl acetate) o. poly(vinyl pivalate) is a linear semicrystalline polymer, which has been widely used as fibers for clothes and industries, films, membranes, medicines for drug delivery system, and cancer cell-killing embolic materials[1-3]. PVA fibers and films have high tensile and compressive strengths, high tensile modulus, and good abrasion resistance due to its highest crystalline lattice modulus. (omitted)

• 한국섬유공학회:학술대회논문집
• /
• 한국섬유공학회 2003년도 가을 학술발표회 논문집
• /
• pp.76-79
• /
• 2003

Recently, many attempts have been made to develop high strength and high modulus fibers from conventional polymers such as poly(vinyl alcohol) (PVA)[1-4] and polyethylene (PE). PVA has potentiality to yield high strength and high modulus fiber, since they have high theoretically attainable moduli because of their planar zig-zag structure. As PVA has a melting temperature as high as 230$^{\circ}C$ in contrast to PE with a low melting temperature such as 130$^{\circ}C$, it seems possible that high strength and high modulus fibers comparable to Aramid can be fabricated from PVA. (omitted)

• Fibers and Polymers
• /
• 제3권2호
• /
• pp.73-79
• /
• 2002

Nanoscaled PVA fibers were prepared by electrospinning. This paper described the electrospinning process, the processing conditions fiber morphology, and some potential applications of the PVA nato-fibers. PVA fibers with various diameters (50-250 nm) were obtained by changing solution concentration, voltage and tip to collector distance (TCD). The major factor was the concentration of PVA solution which affected the fiber diameter evidently. Increasing the concentration, the fiber diameter was increased, and the amount of beads was reduced even to 0%. The fibers were found be efficiently crosslinked by glyoxal during the curing process. Phosphoric acid was used as a catalyst activator to reduce strength losses during crosslinking. Scanning electron micrograph (SEM) and differential scanning calorimetric (DSC) techniques were employed to characterize the morphology and crosslinking of PVA fibers. It was fecund that the primary factor which affected the crosslinking density was the content of chemical crosslinking agent.

• 한국섬유공학회:학술대회논문집
• /
• 한국섬유공학회 2003년도 가을 학술발표회 논문집
• /
• pp.52-54
• /
• 2003

Poly(vinyl alcohol) (PVA) obtained by the saponification of poly(vinyl ester) is a linear semicrystalline polymer; these polymers have been widely used as fibers for clothes and industries, binders, films, membranes, medicines for drug delivery system, and cancer cell-killing embolic materials. PVA fibers have high tensile and compressive strength, tensile modulus, and abrasion resistance because of the highest crystalline lattice modulus. (omitted)

• 한국고분자학회:학술대회논문집
• /
• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
• /
• pp.258-258
• /
• 2006

Electrospun fibers of poly(vinyl alcohol) (PVA) were successfully prepared and applied as drug carriers for transdermal drug delivery system. Sodium Salicylate (SS) was the model drug and it was incorporated in the PVA fibers by adding 20 % of SS in a PVA solution prior to electrospinning. Electrospinning of SS-containing PVA solution resulted in the formation of beaded fibers. In order to control the rate of SS release and decrease water solubility of PVA, the SS-loaded electrospun PVA mat was cross-linked by either glutaraldehyde or glyoxal vapor. The morphology, thermal behavior, swelling behavior, release characteristic, kinetics of drug release and also toxicity of the cross-linked sample were investigated.

• 한국섬유공학회:학술대회논문집
• /
• 한국섬유공학회 2002년도 봄 학술발표회 논문집
• /
• pp.187-190
• /
• 2002

Poly(vinyl alcohol) (PVA) is a representative hydrophilic and water-soluble polymer and widely employed in various applications such as fibers for clothes and industries, films, membranes, medicines for drug delivery system, and cancer cell-killing embolic materials. Moreover, PVA fibers, gels, and films are potentially high-performance materials because they have high tensile and impact strengths, high tensile modulus, high abrasion resistance, excellent alkali resistance, and oxygen barrier property which are superior to those of any known polymers[1,2]. (omitted)

• Fibers and Polymers
• /
• 제7권3호
• /
• pp.229-234
• /
• 2006

Poly(vinyl acetate) (PVAc)/poly(vinyl alcohol) (PVA)/montmorillonite (MMT) clay nanocomposite microspheres with a core/shell structure have been developed via a suspension polymerization approach. In order to prepare the PVAc/ MMT and PVAc/PVA/MMT nanocomposite microspheres, which are promising precursor of PVA/MMT nanocomposite microspheres, suspension polymerization of vinyl acetate with organophilic MMT and heterogeneous saponification were conducted. A quaternary ammonium salt, cetyltrimethylammonium bromide, was mixed with the MMT in the monomer phase prior to the suspension polymerization. The rate of conversion decreased with an increase in MMT concentration. The incorporation of MMT into the PVAc was verified by FT-IR spectroscopy. Organic vinyl acetate monomers were intercalated into the interlayer regions of organophilic clay hosts and followed by suspension polymerization. Partially saponified PVA/MMT nanocomposite microspheres with a core/shell structure were successfully prepared by heterogeneous saponification.

• Fibers and Polymers
• /
• 제2권2호
• /
• pp.108-115
• /
• 2001

Vinyl acetate was polymerized in ultraviolet-ray initiated bulk system at low temperatures using 2,2-azobis(2,4-dimethylvaleronitrile) (ADMVN) or 2,2-azobis(isobutyronitrile) (AIBN) as the photoinitiator, respectively. High molecular weight (HMW) poly(vinyl alcohol) (PVA) having number-average degree of polymerization ($P_n$) of 3,900-7,800 and syndiotactic diad (S-diad) content of 52.5-54.0% could be prepared by complete saponification of synthesized linear poly(vinyl acetate) (PVAc) having $P_n$ 5,900-9,400 obtained at conversion of below 30%. $P_n$ of PVA using ADMVN was larger than that of PVA using AIBN. On the other hand, conversion of the former was smaller than that of the latter, and it was found that the initiation rate of the ADMVN was lower than that of AIBN. This could be explained by a fact that the rate of photolysis of AIBN is faster than that of ADMVN due to the higher quantum yield or dissociation rate constant of AIBN than that of ADMVN. The $P_n$, syndiotacticity, and whiteness of PVA from PVAc polymerized at lower temperatures were superior to those of PVA from PVAc polymerized at higher temperatures.

• 폴리머
• /
• 제37권4호
• /
• pp.486-493
• /
• 2013

고분자 색전 코일을 제조하기 위하여 교대배열 PVA(s-PVA) 용액을 제조하고 젤방사 조건의 최적화를 위해 고분자용액의 유변학적 특성을 분석하였다. 현탁중합을 통해 비누화도 99%, 교대배열기 함량 56%인 s-PVA를 제조하였고 고분자 용액의 농도에 따른 점도 변화 측정을 통해 최적의 방사농도를 13 wt%로 선정하였다. S-PVA 젤 섬유의 연신비에 따른 구조, 형태, 인장 특성을 측정하였다. S-PVA 젤 섬유의 연신비가 증가함에 따라 인장강도가 증가하였고, 최대 연신비인 15배 연신하였을 때 인장강도는 580 MPa이었고 절단신도는 연신비가 증가함에 따라 감소하는 경향을 나타냈다. S-PVA 젤 섬유는 연신비에 따라 결정구조가 발달하고 배향도가 증가하는 경향을 나타내었다. 색전 코일 제조 시의 열처리온도에 따른 코일의 형태 안정성을 살펴 본 결과 열처리온도가 높을수록 코일의 형태안정성이 우수하였으며 금속 색전 코일로 제조되는 1차 코일 및 2차 코일 형태를 s-PVA 섬유를 이용해 제조하였고 이를 통해 금속 색전 코일의 고분자로의 대체 가능성을 확인하였다.