Abstract: A process of preparing film, fibers and other shaped articles by nitrosating a polyhydroxy polymer in a reaction medium containing a solubilizing agent for the resulting polyhydroxy polymer nitrite ester and a suitable proton acceptor, bringing the reaction mixture into the desired shape and regenerating and separating the polyhydroxy polymer by contact with a protic solvent in the presence of an acid catalyst. The polyhydroxy polymer may be a polyvinyl alcohol, cellulose or other polysaccharide, and mixtures thereof. Also dissolved in the reaction medium may be an organic solvent soluble polymer substantially lacking hydroxyl groups. If mixtures of polyhydroxy polymers or of polyhydroxy polymers lacking hydroxyl groups and organic solvent soluble polymers are employed the resulting films, fibers or other shaped articles consist of homogeneous and intimate mixtures of all the polymers originally present in solution.

Abstract: Cellulose sulfate esters are cross-linked with tetravalent metal ions at a threshold pH of about 3.0 or higher. The cross-linked products have a higher aqueous viscosity and are more highly pseudoplastic than the precursor cellulose sulfate and may also exhibit a relatively high yield point. The products may be employed in forming thickened aqueous compositions and cohesive gel-like compositions.The presence of other metallic ions, in addition to the tetravalent metal ions, is beneficial and enhances the viscosity increase produced by cross-linking of the cellulose sulfate with the tetravalent metal ions.

Abstract: A process for preparing a sulfate ester of a polyhydroxy polymer which is a partially substituted polysaccharide or a polyvinyl alcohol which contains ether groups, ester groups other than sulfate, or a mixture of ether groups and ester groups other than sulfate. A nitrite ester of the partially substituted polymer is reacted with sulfur trioxide or a complex thereof to obtain a mixed nitrite:sulfate ester which is then reacted with a protic solvent to remove residual nitrite ester groups.A process for preparing a substantially uniformly substituted colloidal cellulose sulfate having a degree of substitution of about 1.1 to 2.0. A nitrite ester of cellulose having a degree of substitution less than about 2 is reacted with sulfur trioxide or a complex thereof to obtain a mixed nitrite:sulfate ester which is reacted with a protic solvent to remove residual nitrite ester groups.A process for preparing a substantially uniformly substituted cellulose sulfate having a degree of substitution ranging up to about 1.1.

Abstract: A process for preparing a cellulose sulfate ester by reacting a hydrated cellulose containing about 4 to about 12 percent by weight of water with dinitrogen tetroxide or nitrosyl chloride in the presence of a proton acceptor and a reaction solvent which is a swelling or solubilizing agent for a reaction product. Alternatively, the cellulose reactant may contain less than about 4 percent by weight of water by washing hydrated cellulose containing in excess of 4 percent of water with a highly polar aprotic solvent to reduce the water content.A process for simultaneously preparing a sulfate ester of cellulose and an alkyl nitrite by reacting a nitrite ester of cellulose with sulfur trioxide or a complex thereof to obtain a mixed nitrite:sulfate ester which is reacted with an organic alcohol containing up to about 10 carbon atoms.

Abstract: A water-soluble sulfate ester of cellulose having a degree of substitution of about 0.3 to about 1.0 with a substantially uniform distribution of sulfate ester groups among the polymer units of the cellulose. A thickened aqueous medium containing water and said water-soluble sulfate ester of cellulose having a degree of substitution of about 0.3 to about 1.0.A water-insoluble sulfate ester of cellulose which is highly swellable in the presence of water and has a degree of substitution of up to about 0.3 with the sulfate ester groups being substantially uniformly distributed among the polymer units of the cellulose.A water-soluble colloidal cellulose sulfate ester having a degree of substitution of about 1.3 to about 2 with the sulfate ester groups being substantially uniformly distributed among the polymer units of the cellulose. A thickened aqueous medium containing water and said water-soluble cellulose sulfate ester having a degree of substitution of about 1.3 to about 2.0.

Abstract: A polysaccharide or polyvinyl alcohol containing a mixture of nitrite ester groups with sulfate or nitrate ester groups with the mixture of ester groups being substantially uniformly distributed among the polymer units of the polysaccharide or polyvinyl alcohol.A nitrite ester of a polysaccharide alcohol having a degree of substitution of less than about 2.0. A nitrite ester of polyvinyl alcohol having a degree of substitution of 1.0 or less.

Abstract: Preparation of partially substituted nitrate and sulfate esters of polysaccharides or polyvinylalcohol, their esters containing a mixture of nitrite with sulfate or nitrate groups, aqueous media thickened with such esters, the simultaneous preparation of such esters and alkyl nitrites or such esters and inorganic nitrites or nitrates and resulting products, useful as thickeners, films, fibers and in many other applications.

Abstract: A polysaccharide or polyvinyl alcohol containing a mixture of nitrite ester groups with sulfate or nitrate ester groups with the mixture of ester groups being substantially uniformly distributed among the polymer units of the polysaccharide or polyvinyl alcohol.A nitrite ester of a polysaccharide alcohol having a degree of substitution of less than about 2.0. A nitrite ester of polyvinyl alcohol having a degree of substitution of 1.0 or less.