In membrane processes, the membrane quality is at the core of the process. In this context, taking an interest in membrane materials is important. This paper focuses on polymer materials used in the preparation of ultrafiltration membranes. Two polymers were chosen for their recognized quality as membrane materials, poly(acrylonitrile) and polysulfone. Poly(acrylonitrile) homopolymer, PAN, poly(acrylonitrile-co-hydroxyethyl methacrylate) copolymers, AH1 and AH3, poly(acrylonitrile-co-sodium styrene sulfonate) copolymers, AS1 and AS3, and poly(acrylonitrile-co-hydroxyethyl methacrylate-co-sodium styrene sulfonate) terpolymers, AH1S2, AH1.5S1.5, and AH2S1 were synthesized and materials of various compositions were obtained and used to prepare ultrafiltration membranes by classical phase-inversion method. The PAN-based membranes were used in a laboratory-scale study to ultrafilter aqueous solutions of carboxymethylcellulose, CMC. Before use, the membranes were characterized employing Fourier Transform Infrared Spectroscopy (FTIR), to verify the occurrence of copolymerization, and thermogravimetric analysis (TGA), to examine the thermal properties of the polymers. The paper gives a comparison between PAN-based co and terpolymers and polysulfone-based polymer bends formed by polysulfone (PS) and poly(sodium 4-styrene sulfonate) (PSSNa), PS-S1 and PS-S3. The membranes AH3, AS1, and AH2S1 were the most efficient with regard to the separation ability. Besides, their solvent flux regeneration after use was the best, indicating promising durability for practical usage.