期刊
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
卷 127, 期 1, 页码 885-894出版社
SPRINGER
DOI: 10.1007/s10973-016-5811-1
关键词
Polyvinyl alcohol (PVA); DSC; Thermogravimetric analysis; Thermogravimetric analysis; Self-nucleation
资金
- National Science Foundation [DMR-1206010, DMR-0520655]
- Division Of Materials Research
- Direct For Mathematical & Physical Scien [1608125] Funding Source: National Science Foundation
Polyvinyl alcohol (PVA) is a hydrophilic, biodegradable, semicrystalline polymer with a wide array of commercial uses ranging from textiles and packaging to medicine. Film samples of PVA were investigated to assess crystallization and melting behavior during self-nucleation experiments and thermal degradation, using differential scanning calorimetry (DSC) and thermogravimetric (TG) analysis, respectively. TG results show that degradation occurred at temperatures in excess of 200 A degrees C which is close to the observed peak melting temperature of 223 A degrees C. PVA was heated to various self-nucleation temperatures, T (s), within its melting range, and then cooled and reheated. Three distinct crystallization regimes were observed upon cooling, depending upon the self-nucleation temperature (T (s)) selected. At low values of T (s), T (s) < 227 A degrees C, PVA only partially melts, and upon cooling the residual crystals anneal and become more stable. At intermediate values of T (s), 228 A degrees C < T (s) < 234 A degrees C, PVA was found to crystallize exclusively from self-nucleation. For T (s) > 235 A degrees C, the PVA melts completely and absence of self-nucleation sites causes crystallization to occur at lower temperatures.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据