Models For Insulation Resistance Of Insulating Material Polyetherimide (PEI) Under The Space Environment Conditions '

Polyetherimide (PEI) is one kind of thermoplastics. Due to its excellent electrical, heated and mechanical properties, PEI has been widely used in industrial application and has achieved remarkable economic and technological benefits. In order to predict the life of aerospace electrical connectors and improve its stability and reliability, we have to study the deterioration of insulating properties of PEI which is used as typical materials for aerospace electrical connectors under the space environment condition. Because the insulating properties of insulating materials is dependent on insulation resistance, and precise measure of insulation resistance can reflect the stability and reliability of insulation materials, this thesis attempts to establish a theoretical model for insulation resistance of PEI under space environment conditions.The focuses of the present thesis are as follows: The first chapter introduces the background of applications of insulation materials, then gives a brief introduction of the electrical connectors and PEI, and at last focuses on an overview of domestic and foreign researches on insulation; Under the high and low temperature cycle condition, the insulation resistance of PEI is studied and its model is established in the second chapter, and measure the insulation resistance of PEI under the different constant temperature. In the third chapter, under the ultraviolet radiation condition, a model for insulation resistance of PEI is derived; The fourth chapter studies the effect of atomic oxygen on insulation resistance of PEI, and establishes the model under this condition; The fifth chapter synthetically investigates the impact of high and low temperature cycle, ultraviolet radiation and atomic oxygen on the PEI, then establishes the model for insulation resistance of PEI under these conditions; The sixth chapter presents a summary and outlook of this work.Only a small part about this subject has been completed in this work, and there are still many interesting work can be investigated furtherly. For example, measuring insulation resistance of PEI under conditions of low temperature, ultraviolet radiation and atomic oxygen; improving the model established in this work on insulation resistance of PEI from theory and experiment, and so on.