Follow-up on the effects of the space environment on UHCRE thermal blankets

An overview of the effects of the space environment on the thermal blanket of the UHCRE experiment is presented with an emphasis on atomic oxygen (AO) erosion. A more accurate value for FEP Teflon reaction efficiency is given and corresponds, at normal incidence, to 3.24 10(exp -25) cu cm/atomic, therefore, the FEP Teflon erosion corresponding to the Long Duration Exposure Facility (LDEF) total mission is 29.5 microns. A power 1.44 of the cosine of the incident angle of the oxygen atoms is found. It is shown that this value is not far from the power found using Fergusson's relationship between efficiency and energy of the O-atoms. An hypothesis concerning the effect of oxygen ions (O(+)) is also presented. The presence of oxygen ions may explain the different results obtained from different flights and from laboratory tests. Finally an XPS analysis of Chemglaze Z306(tm) black paint demonstrates the presence of silicone in the paint which may explain part of the contamination found on LDEF