聚乙烯醇／壳聚糖合金膜的相容性

本文通过 WAXD、DSC动态力学和应力一应变测量对 PVA/CS合金膜的聚集态结构进行了研究。发现,合金膜中的PVA结晶完善性变差,结晶度和结晶熔融峰温度随CS含量增加而降低。合金膜中的CS晶型发生了转化。动态力学损耗谱显示,合金膜中仍保持单组分的玻璃化松弛。当PVA含量大于50%％时,两个Tg峰中间产生一新的力学损耗峰。合金膜的模量和断裂强度高于单组分,而断裂伸长率低于单组分,这都表明,PVA与CS间存在强的相互作用,该共混体系为部分相容体系。

Compatibility of Polyvinyl alcohol / Chitosan Alloy Membrane

The aggregated state structure and mcchanical properties of polyvinylalcohol(PVA)/chitosan(CS) alloy membrane were studied by WAXD, DSC,dynamic--mechanic and stress--strain measurments. It was found that the crystallinity and crystal melting temperature of PVA de-crease with CS content inereasing and the CS crystal form was transformed in the alloymebrance. The dynamic mechanical loss spectrum show that both PVA and CS glasstransitions were preserved in the blend, but a new relaxation peak between PVA andCS glass transition was exhibited when the PVA content was more than 50wt%. Theyoung's module and break strength of the alloy membrane are higher than those of theindividual component, and the extension ratio is lower. The results prove that theinterreaction between PVA and CS is strong and the blend is a patt--compatibility sys-tem.