Cellulosic membranes

Cellulosic membranes, characterized by the fact that a mixture of cellulose and compounds of the type [A-]n is regenerated from solutions in cellulose solvents to form hollow fibers, tubes, or foils and regenerated in precipitants, where A is one or more acid or basic groups, selected from -COOH, -SO3H, -PO3H2, -NH2, -NHR, -NR2, -+NR3, and -NR2->O, where R=B and/or R=alkyl group with 1 to 6 carbon atoms and/or R=a phenyl group, and B is a straight-chain or branched, possibly substituted group, selected from alkyl groups with at least 10 carbon atoms, arylalkyl groups with at least 10 carbon atoms, or a polymerizable monomeric group such as alkene, alkyne, cycloolefin, arene, arylalkene, arylalkyne, allyl, and vinyl group, optionally substituted, in which the chain can be interrupted by heteroatoms such as O, S, N, P, B, and Si and n=1 or, in the case of polymerizable monomers, at least 10 and the percentage of cellulose in the mixture is at least 65%.