Five new co-poly(imide siloxane)s have been prepared by reacting two diamine monomers 9, 10-bis [3'-trifluoromethyl-4' (4 ''-aminobenzoxy)benzyl]anthracene (TFAA) and amino-propyl terminated polydimethylsiloxane (APPS) together with different commercially available dianhydrides like benzene-1,2,4,5-tetracarboxylic dianhydride (PMDA), 4,4'-(hexafluoro-isopropylidene)diphthalic anhydride (6FDA), 4,4'-oxydiphthalic anhydride (ODPA), 4,4'-(4,4'-Isopropylidenediphenoxy)bis(phthalic anhydride) (BPADA) and benzophenone-3,3',4,4'-tetracarboxylic dianhydride (BTDA). In each case the siloxane loading was adjusted to about 40 wt.% in the respective copolymers. The polymers were either synthesized by the one-pot solution imidization method or by the thermal imidization route. The synthesized polymers show predominantly good solubility in different organic solvents. The resulting polymers have been characterized by gel permeation chromatography, infrared and nuclear magnetic resonance techniques. These polyimides show good thermal stability with decomposition temperature (5% weight loss) up to 463 degrees C in nitrogen. Transparent thin films of these polyimides exhibit tensile strengths up to 31 MPa, a modulus of elasticity up to 0.63 GPa and elongation at break up to 110%.