In Situ Generation of an Organosilicon Nanophase

As described in detail elsewhere, the preparation of Pl-based PNC involved the following steps (i) synthesis of a polyamic acid with ethoxysilane end-groups (PAAS), (ii) preparation of the nanocomposite precursors by the addition of the required amount of methyl triethoxysilane (MTS), (Hi) MTS hydrolysis in the cast NCP films, and (iv) imidization of the PAAS to the corresponding polyimide by stepwise heating of the thin NCP films for 2 h at each of the following temperatures 60,100,120,150,200, and 250 C and by post-cure for 5 hat300-315°C. 

The anticipated (ideal) structure of the final product can be represented schematically as follows  

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