Melting, regelling, and remelting of poly(vinyl alcohol) hydrogels

✍ Scribed by Kazuo Yamaura; Ikuo Kurose; Tetsuya Tanigami

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 414 KB
• Volume: 60
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/(sici)1097-4628(19960509)60:6<897::aid-app13>3.0.co;2-u

✦ Synopsis

The melting behaviors of hydrogels of syndiotacticity-rich poly(viny1 alcohol) (s-PVA), derived from vinyl trifluoroacetate, during heating at various rates of rising temperature were examined. For the hydrogels with the polymer concentrations above 5 g/dL chilled at the temperatures of 0 -40°C, the melting temperature increased with a decrease in the rate of rising temperature. During rising temperature at lower rates, the phase separation with spinodal decomposition progressed even in gels and the microcrystals, which play an important role as the junction points, propagated to thermally more stable size. The small, broad exothermic peaks during rising temperature of s-PVA hydrogels in DSC thermograms was found at the temperature ranges of 10 -30 and 45 -60°C.