摘要
用差示扫描量热法研究了聚左旋乳酸（ＰＬＬＡ）及其与羟基磷灰石、甲壳素和甲壳胺复合后的非等温结晶行为，分别用Ｍａｎｄｅｌｋｅｒｎ和Ｚｉａｂｉｃｋｉ两种处理方法获得了ＰＬＬＡ及其在复合体系中的非等温结晶动力学参数．结果表明：随冷却速率的增大，ＰＬＬＡ及其在复合体系中的结晶度迅速下降，Ａｖｒａｍｉ结晶指数ｎ值减小．复合组分可使ＰＬＬＡ的ｎ值增大，有利于ＰＬＬＡ结晶按三维方式发育生长．ＰＬＬＡ及其在复合体系中的非等温结晶速率常数Ｚｃ值（Ｍａｎ－ｄｅｌｋｅｒｎ方法）和动力学结晶能力参数Ｇ值（Ｚｉａｂｉｃｋｉ方法）均随冷却速率增大而增大，而比动力学结晶能力参数Ｇｃ值则与冷却速率无关，但受复合组分影响，其中羟基磷灰石使Ｇｃ值减小，而甲壳素和甲壳胺使Ｇｃ值增大．
The nonisothermal crystallization behaviours of poly(Llactic acid)(PLLA) and its composites with hydroxyapatite(HA), chitin(CHI), and chitosan(CHS) respectively were investigated by differential scanning calorimetry(DSC) The kinetic parameters of nonisothermal crystallization were derived based upon Mandelkern’s and Ziabicki’s methods Results show that with increasing cooling rate, the crystallinities of PLLA and PLLA in the composites decrease rapidly and the Avrami exponent n get smaller The components in the composites are of increasing the n of PLLA and thus favourable to the PLLA crystal organizations growing in 3dimension The nonisothermal crystallizationrateconstant Zc obtained according to Mandelkern’s method and the parameter of kinetic crystallizability G derived from Ziabicki’s theory increase with the increase of cooling rate while the specific kinetic crystallizability Gc is independent of cooling rate; However, Gc is affected by the components in the composites, in which HA makes the Gc smaller while CHI and CHS increase the Gc.
出处
《中山大学学报（自然科学版）》
CAS
CSCD
北大核心
1998年第4期71-75,共5页
Acta Scientiarum Naturalium Universitatis Sunyatseni
基金
广东省自然科学基金
关键词
聚左旋乳酸
非等温
结晶动力学
复合体系
polyl(actic acid), nonisothermal crystallization kinetics, hydroaxyapatite, chitin, chitosan
