Phase separation structure in poly(vinyl alcohol)/silk fibroin blend films

✍ Scribed by Tanaka, Toshihisa; Tanigami, Tetsuya; Yamaura, Kazuo

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 642 KB
• Volume: 45
• Category: Article
• ISSN: 0959-8103
• DOI: 10.1002/(sici)1097-0126(199802)45:2<175::aid-pi883>3.0.co;2-k

✦ Synopsis

Blend Ðlms of a commercial poly(vinyl alcohol) (a-PVA) derived from vinyl acetate and silk Ðbroin (SF) obtained from degummed silk were prepared by mixing the aqueous solutions of both samples. A plain weave structure was recognized only in the blend Ðlms, whereas no structure was found for the superimposed Ðlms of both samples. The phase separation structure of the blend Ðlms was examined by microscopic observations elongation, tensile tests, and IR measurements. The microphase separation region increased with increase in the degree of polymerization of the PVA. In the IR spectra of the blend Ðlms with high PVA contents cast under certain conditions, the absorption peak attributed to the cross-b-form conformation of SF appeared strongly. Gelatin, a watersoluble and natural polymer, was also used for comparison with SF. The ternary phase diagram in an system was obtained experimentally a-PVA/gelatin/H 2 O and the critical point was used to estimate the interaction parameter between PVA and gelatin molecules. The phase separation structure and the interaction between PVA and SF molecules were also discussed taking into consideration the results of the a-PVA/gelatin system. 1998 SCI.