Cellulose-containing composites based on copolymers of acrylic acid with styrene, 4-chloro-methyl-styrene and maleic anhydride were prepared for proton conducting membranes. The influence of the substrate on the copolymer composition as well as the copolymer/cellulose ratio on the basic properties of composite materials is discussed using the FT-IR, optical microscopy, SEM, TGA-DSC and conductivity measurements. Moderate water swelling (2-10%) of the synthesized membranes provided volume resistivities, down to 1 x 10(5) Omega . cm, adequate for further processing as proton exchange membrane.