Abstract: Composite membrane-for separating water from fluid mixtures containing organic components by means of pervaporation comprising a separating layer of cross-linked polyvinyl alcohol, which has been subjected to a post-cross-linking by treatment with acids acting in the vapor phase on the polyvinyl alcohol layer. The acids are preferably hydrohalic acids, sulfurous acid, sulfuric acid, nitrous acid, nitric acid or acetic acid.

Abstract: The subject of the invention is a water-soluble macromolecular conjugate of hemoglobin characterized in that it is constitutedon the one hand, by hemoglobin,on the other, by a water-soluble polymer P containing polar groups, this macromolecular conjugate contains Z sites, bound to the polymer P and containing at least one negative charge carried for example by sulfate groups, the polymer P being bound to hemoglobinon the one hand, through the intermediary of at least one linkage established between at least one of the Z sites contained in the polymer and hemoglobin,and, on the other, through the intermediary of at least one covalent linkage established between the polymer and hemoglobin, or between at least one of the Z sites contained in the polymer and hemoglobin.The macromolecular conjugates according to the invention exhibit a lower affinity for oxygen than that of free hemoglobin.