Preparation of functional polymers and block copolymers via post polymerization modifications for biomedical applications The research in this thesis focuses predominately on the preparation and characterization of polymers and block copolymers containing ionizable or charged moieties. In the first part of this thesis the synthesis and polymerization of various monomers is described which are converted into polyelectrolytes and polyampholytes with a high charge density later on. Such functional materials are highly versatile finding use as surfactants in heterogeneous catalysis or in biomedical applications. In the second part of this thesis polyether based block copolymers are prepared by anionic ring opening polymerization for use in gene and drug delivery.