The application of GC/MS in spacecraft pollution control

Abstract

In recently years, the problems of spacecrafts contamination occur sequentially, which can result in sensitive spacecraft's hardware out of work. The chief reason of contamination is vacuum outgassing of non-materials. The gray cable is used widely in spacecrafts. When the gray cable locates in vacuum environment, it can release gases inevitable, which form contamination film once deposited on sensitive surfaces. For avoiding the similar problems happened on other spacecrafts, it is very necessary to study the vacuum outgassing characteristics of the gray cable and preprocess before using it. The vacuum outgassing characteristics of the gray cable are studied in this paper for the first time. First, total mass loss (TML) and collected volatile condensable materials (CVCM) of gray cable are obtained after outgassing experiments for 24 hours. Then, the variety between TML and outgassing time is studied in this paper, too. At last, the components of outgassing products are also provided in different temperature. The results show that TML of gray cable is 1.2%o even at a lower temperature of 65 °C. There is sharply increase of TML in first 24 hours, and gently increase after 24 hours. In addition, the main components of outgassing products indicate that they are different in different temperatures, which are phthalates at a temperature of 65 °C and are siloxanes at temperatures of 85 °C and 105 °C. The results can assist to directing the use and improvement of gray cable. It can also provide advantage proof for setting vacuum bake-out parameters of gray cable.