Atomic oxygen resistance

Recently siloxane-imide copolymers have received specific attention due to various unique properties displayed by these materials which include fracture toughness, enhanced adhesion, improved dielectric properties, increased solubility, and excellent atomic oxygen resistance 1S3). The first report on the synthesis of poly(siloxane-imides) appeared in 1966, where PMDA (pyromellitic dianhydride) was reacted with an amine-terminated siloxane dimer and subsequently imidized 166>. Two years later, Greber 167) reported the synthesis of a series of poly(siloxane-imide) and poly(siloxane-ester-imide) copolymers using different siloxane backbones. However no physical characterization data were reported. 

ATOMIC OXYGEN RESISTANT POLY(CARBORANE SILOXANE) COATINGS... 

Polyimides are of particular interest for many engineering applications due to their excellent thermal and mechanical properties in the aerospace and microelectronics industries. Many important applications have been developed (1,2 The poiyimide siloxane segmented copolymers have been of particular interest since incorporation of amine functionalized polysiioxanes into polyimides have resulted in improved solubility and processability, decreased water absorption, atomic oxygen resistance (3), lower dielectric constants (4) and enhanced adhesion (5). The copolymers are generally synthesized as shown in Scheme 1 from a combination of a dianhydride and... 

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