A polysiloxane/polyimide block copolymer composition with improved resistance to steam comprising: a polysiloxane/polyimide block copolymer comprises repeating groups of formula and formula: wherein b is from 10 to 1,000, g is from 1 to 50, a is from 10 to 500, R 1-6 are independently selected from substituted or unsubstituted, saturated, unsaturated, or aromatic monocyclic or polycyclic groups having 5 to 30 carbon atoms, substituted or unsubstituted alkyl groups having 1 to 30 carbon atoms, substituted or unsubstituted alkenyl groups having 2 to 30 carbon atoms, or combinations thereof, and V is a tetravalent linker selected from substituted or unsubstituted, saturated, unsaturated, or aromatic monocyclic or polycyclic groups having 5 to 50 carbon atoms, substituted or unsubstituted alkyl groups having 1 to 30 carbon atoms, or combinations thereof; R7 in formula includes substituted or unsubstituted divalent organic radicals such as: aromatic hydrocarbon radicals having 6 to 20 carbon atoms and halogenated derivatives thereof; straight or branched chain alkylene radicals having 2 to 20 carbon atoms; cycloalkylene radicals having 3 to 20 carbon atoms; or divalent radicals of the general formula wherein Q includes a divalent moiety comprising -O -S-, -C -, -SO 2 -, -SO-, -C y H 2y - (y being an integer from 1 to 36), and halogenated derivatives thereof, including perfluoroalkylene groups. and from 0.1 to 10 wt% of a combination of, a polyfunctional epoxide compound, and a hydrotalcite compound, wherein the polyepoxide compound has a weight average molecular weight (Mw) from 200 to 18000 Daltons (determined by gel permeation chromatography using polystyrene calibration standards), and the hydrotalcite compound has an average particle size from 1 to 10 micrometers, and wherein the polyepoxide compound and hydrotalcite compound are used in combination having from 1 to 99% polyepoxide compound and 99 to 1% hydrotalcite compound. a polysiloxane/polyimide block copolymer comprises repeating groups of formula and formula: wherein b is from 10 to 1,000, g is from 1 to 50, a is from 10 to 500, R 1-6 are independently selected from substituted or unsubstituted, saturated, unsaturated, or aromatic monocyclic or polycyclic groups having 5 to 30 carbon atoms, substituted or unsubstituted alkyl groups having 1 to 30 carbon atoms, substituted or unsubstituted alkenyl groups having 2 to 30 carbon atoms, or combinations thereof, and V is a tetravalent linker selected from substituted or unsubstituted, saturated, unsaturated, or aromatic monocyclic or polycyclic groups having 5 to 50 carbon atoms, substituted or unsubstituted alkyl groups having 1 to 30 carbon atoms, or combinations thereof; R7 in formula includes substituted or unsubstituted divalent organic radicals such as: aromatic hydrocarbon radicals having 6 to 20 carbon atoms and halogenated derivatives thereof; straight or branched chain alkylene radicals having 2 to 20 carbon atoms; cycloalkylene radicals having 3 to 20 carbon atoms; or divalent radicals of the general formula wherein Q includes a divalent moiety comprising -O -S-, -C -, -SO 2 -, -SO-, -C y H 2y - (y being an integer from 1 to 36), and halogenated derivatives thereof, including perfluoroalkylene groups. and from 0.1 to 10 wt% of a combination of, a polyfunctional epoxide compound, and a hydrotalcite compound, wherein the polyepoxide compound has a weight average molecular weight (Mw) from 200 to 18000 Daltons (determined by gel permeation chromatography using polystyrene calibration standards), and the hydrotalcite compound has an average particle size from 1 to 10 micrometers, and wherein the polyepoxide compound and hydrotalcite compound are used in combination having from 1 to 99% polyepoxide compound and 99 to 1% hydrotalcite compound.