• Title/Summary/Keyword: Solvent Annealing

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Preparation of Coil-Embolic Material Using Syndiotactic Poly(vinyl alcohol) Gel Spun Fibers (교대배열 PVA 젤 섬유를 이용한 고분자 색전 코일 제조)

  • Seo, Young Ho;Oh, Tae Hwan;Han, Sung Soo;Joo, Sang Woo;Khil, Myeong Seob
    • Polymer(Korea)
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    • v.37 no.4
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    • pp.486-493
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    • 2013
  • The structure, morphology, and physical properties of syndiotatic poly(vinyl alcohol) (s-PVA) gel spun fibers were investigated to prepare polymeric embolization coils. S-PVA was prepared by saponification of the poly(vinyl acetate)/poly(vinyl pivalate)(PVAc/PVPi) copolymer. The viscosity of s-PVA solutions showed shear thinning behavior and the solution formed a homogeneous phase. Based on shear viscosity change with concentration, the optimum dope concentration was selected as 13 wt%, after which s-PVA fibers were spun and the solvent was removed. The fibers were then drawn with a maximum draw ratio of 15. A polymeric embolization coil was made of the s-PVA gel-spun fibers. The fibers were wound densely onto rigid rod and then annealed at different annealing temperatures. The polymeric embolization coil annealed at $200^{\circ}C$ was similar to metallic coils and its shape was maintained well after extension. Overall, gel-spun PVA fibers performed well for the preparation of primary and secondary coils to replace metallic coils.