As part of our research on new ferroelectric liquid crystalline materials, we present the synthesis, characterization, and physical properties of a new family of polymeric materials, namely AB block copolymers consisting of a non-liquid crystalline chain [poly(isobutyl vinyl ether)] and a chiral liquid crystalline block. The combination of both features gives rise to the appearance of interesting effects on the properties of the polymers : they show the ferroelectric chiral smectic C mesophase at room temperature with low viscosities and low birefringence, due to the presence of the non-liquid crystalline chain. The chiral smectic C phase exhibits the characteristic switching under electric fields. Its electro-optical behavior has been characterized and is different than that of the parent homopolymer. The block copolymers show the typical microphase separation of the two blocks which has been observed by small angle X-ray scattering.