Study On Transamidation In Melt Blending Process Of PA66 And PA6I-6T

Polyamide is a polymer containing-CONH-functional groups in the main chain structure.It is widely used in the fields of textile,electronics,rail transit and aerospace due to its friction resistance,self-lubrication and electrical insulation.It has the second yield among the five engineering plastics.However,with the development of social economy,a single variety of polyamide materials are usually difficult to meet the increasing needs of people.In order to meet these needs,polyamide materials can be modified by melt blending to improve the performance of materials and meet the needs of social development.Researchers have found that transamidation occurs when different polyamide materials are blended,which not only affects the crystallinity,melting point and other properties of the blended samples,but also affects the processing technology such as injection molding and molding.Therefore,this project selects aliphatic polyamide PA66 and semi-aromatic polyamide PA6I-6T as raw materials to explore transamidation between them.Secondly,the effect of inhibitor triaza dicyclodecene(TBD)content on transamidation between PA66 and PA6I-6T was studied.It was found that transamidation between PA66 and PA6I-6T decreased with the increase of inhibitor TBD content.The melting point,melting enthalpy and crystallinity of the blended samples increased first and then decreased.The thermal decomposition temperature of the blended samples has been decreasing.The molecular weight of the blended samples decreased and the molecular weight distribution narrowed.Finally,the non-isothermal crystallization kinetics of PA66 and PA6I-6T blends without inhibitor and with 3 % inhibitor were studied.The results of Avrami equation showed that the addition of inhibitors did not change the crystallization mode of PA66.The crystallization behavior of PA66 and PA6I-6T blends was studied by Mo method and Jeziorny method,and the non-isothermal crystallization activation energy was calculated by Takhor method and Kissinger method.The results show that the addition of inhibitors increases the crystallization peak temperature and the crystallization activation energy.