生物可吸收性甲壳素纤维增强聚(ε-己内酯)复合材料的动态流变特性研究

DYNAMIC RHEOLOGICAL BEHAVIORS OF THE BIOABSORBABLE CHITIN FIBER REINFORCED PCL COMPOSITE

用短切甲壳素纤维增强聚 (ε-己内酯 ) (PCL)制备出新型生物可吸收复合材料 ,通过高级流变扩展系统(ARES)对不同纤维含量 (Cf)的复合材料熔体进行了动态流变特性的研究。结果表明 :纤维含量的增加可以明显提高复合材料熔体的复数模量 (G*)和复数粘度 (η*)。当 Cf从 4 5 %增加到 5 5 %时 ,复合材料熔体在低频区出现了明显的类似于力学性能的“屈服行为”,即 G*不再随频率的改变而变化 ,同时材料的弹性 (G′)要明显高于粘性 (G″)。这种行为可能与纤维在熔体内形成刚性的粒子网络有关 ,对材料的加工成型不利。从双对数坐标下的 G′～ G″曲线和η″～ η′来看 ,纤维的加入明显提高了熔体的弹性 ,延长了熔体的主松弛时间。

A novel bioabsorbable composite was prepared from chitin fiber reinforced PCL matrix, and the ARES was used to study the dynamic rheological behaviors of the composite melts. The increase of C f obviously enhanced the complex modulus and complex viscosity. And when C f was increased from 45% to 55%, the G * curve showed the obvious'yielding behavior' like the mechanical properties, that was to say, the G * had no variation with the change of frequency in a wide range. Moreover, the elasticity ( G ′) was over that of viscidity, which might be contributed to the formation of the 'network of fiber particle', and might result in a disadvantage for processing. For the G ′~ G ″ plots and η ″~ η ′,the reinforcement of fiber increased the elasticity, prolonged the mail relaxation time, and widened the relaxation spectrum of the melts.