Patent ID: 7803896
Filing Date: 2010-09-28
Classification: C08G,C08L

Abstract:
1. A method for preparing polyimide-titania hybrid material, which comprises the steps of: (a) reacting an aromatic dianhydride monomer with an aromatic diamine monomer and optionally carboxylic acid-substituted aromatic diamine monomer in a mole ratio (x/y) of (moles of aromatic dianhydride)(in terms of x)/(total moles of aromatic diamine and carboxylic acid-substituted aromatic diamine)(in terms of y) is more than 1 to subject the dianhydride to a ring-opening reaction to obtain polyamic acid having a terminal anhydride group; (b) further subjecting the polyamic acid having a terminal anhydride group from step (a) to ring-opening by adding aniline and/or aminobenzoic acid to obtain a polyamic acid having pendent and/or terminal carboxylic acid group, wherein the amount of the aniline and/or aminobenzoic acid is 2×(x−y) in total moles; (c) subjecting the polyamic acid having pendent and/or terminal carboxylic acid group from step (b) to imidization (cyclization) to obtain a polyimide having pendent and/or terminal carboxylic acid group; and (d) reacting the polyimide having pendent and/or terminal carboxylic acid group from step (c) with titanium alkoxide to coordinate the carboxylic acid group with titanium atom, then subjecting to hydrolysis and condensation to obtain the polyimide-titania hybrid material.