纳米二氧化钛对聚酯纤维结晶性能的影响

Influence of nano-TiO_2 on crystallization kinetics of polyester

采用钛酸丁酯表面修饰纳米二氧化钛,并添加到聚酯合成过程中,以改性聚酯纤维,发现改性后的聚酯纤维上染速率提高了近3倍。针对这一现象,通过透射电镜和DSC差热仪进行观测,发现纳米二氧化钛较均匀地分散在聚酯内部,并提高了聚酯纤维的玻璃化温度,说明纳米粒子的表面修饰与聚酯有良好的相容性。进一步采用修正Avrami方程、Kissinger法和Jeziomy法对其非等温结晶过程进行分析发现,纳米二氧化钛降低了聚酯结晶活化能,提高了结晶速度,纳米粒子可作为晶核使聚酯部分转向异相结晶。研究结果表明,纳米二氧化钛改变了聚酯纤维结晶行为,促进了染料分子的吸附上染和热性能的提高。

Polyester was synthesized with nano-TiO2 particles modified with titanium tetrabutoxid.It is found that the dyeing rate has increased three times.TEM and DSC were used to analyze this phenomenon.It is shown that nano-TiO2 well dispersed in polyester and the glass transition temperature was increased,indicating well compatibility between surface modified particles and polyester.The Avrami theories,Jeziorny theories and Kissinger method were adopted to further analyze the non -isothermal crystallization,and the results showed that nano-TiO2 remarkably reduce the crystallization active energy of polyester and improve the crack crystalline growth velocity.The nano particles could be as crystalline nucleation to drive crystallization from homogeneous to heterogeneous.The experiments revealed that the crystallization of polyester was changed with nano-TiO2,promoting dyestuff adsorbing and rising in thermal properties.