A thermoplastic composition comprises a sulfonate end-capped polycarbonate of formula: Z-S(O).sub.2--O-(-L-).sub.m-O--S(O).sub.2-Z wherein each Z is independently an alkyl or aryl group, wherein -(-L-).sub.m- is a polycarbonate linking group with m units of linking unit L, and wherein m is at least one. Methods of making the sulfonate end-capped polycarbonate and thermoplastic composition, and articles prepared therefrom, are also disclosed.