摘要:
Hollow cellulosic fibers are produced by nitrosating and dissolving a cellulosic material in an aprotic solvent selected from the group consisting of a dialkylacylamide and dimethylsulfoxide and regenerating the dissolved cellulose by contacting the cellulose solution with a regenerant. The regenerant is n-octanol where the solvent is a dialkylacylamide and n-hexanol where the solvent is dimethylsulfoxide. The fibers are hollow as regenerated and require no special spinnerette designs nor special spinning conditions.
摘要:
Shaped cellulosic fibers are produced by nitrosating and dissolving a cellulosic material in an aprotic solvent selected from the group consisting of a dialkylacylamide and dimethylsulfoxide and regenerating the dissolved cellulose by contacting the cellulose solution with a regenerant. The regenerant is butanol, pentanol or benzyl alcohol where the solvent is a dialkylacylamide and propanol, butanol or benzyl alcohol where the solvent is dimethylsulfoxide. The fibers have a generally crenulated shape as regenerated and require no special spinnerette designs nor special spinning conditions.
摘要:
Regenerated cellulosic articles are produced by nitrosating and dissolving cellulose in a dialkylacylamide solvent, such as dimethylformamide, and regenerating the dissolved cellulose by passing into a coagulant bath. The coagulant comprises water or a 1 to 4 carbon atom aliphatic monohydric alcohol and a soluble reactive base, the latter in an amount ranging from 6% to 25% by weight of the regenerant. The process produces regenerated cellulose products of improved resistance to alkaline solubility.
摘要:
Acrylated cotton fabric is reacted with water-N,N-dimethylformamide solutions of acrylamide and then exposed to near ultraviolet light in an inert atmosphere to produce crosslinked acrylated cotton fabrics with durable press properties. The treatment is also applicable to methacrylated cotton fabric and the results obtained are similar.
摘要:
In a method for forming a cellulose tube suitable for use as a food casing, in which a solution of nonderivatized cellulose, tertiary amine N-oxide and water is extruded through a die gap and the extruded tube downwardly flowed through an air length while being internally cooled, and passed into a water bath, the tube transverse direction tensile strength is substantially increased by drawing the extruded tube through an air length of at least about six inches.
摘要:
Processes for manufacturing starch copolymer compositions are provided. In one process, a modified starch is reacted with a hydrophilic vinyl monomer to produce a starch copolymer gel which is, in turn, divided in a plurality of gel fragments. The gel fragments are then dried with a stream of gel to produce a flowable, particulate starch copolymer composition. In another process, water is evaporated from the copolymer gel and further polymerization of vinyl monomers is inhibited during the evaporating by any of a variety of means such as reducing the level of residual vinyl monomer or avoiding conditions which initiate polymerization.
摘要:
Methylated, ethylated or carboxymethylated starch products which have, per anhydroglucose unit within the starch molecule, an average of from about 0.03 to about 1.0 methyl, ethyl or carboxymethyl substituents covalently bonded thereto and which contain a combined total of less than 1 weight percent, on a dry starch solids weight basis, of polyvalent inorganic anions, monovalent inorganic anions and methylsulfate and ethylsulfate anions are particularly well suited for use as protective colloids in emulsion polymerization or copolymerization processes.
摘要:
A cold-water-swellable granular starch which affords aqueous solutions or dispersions having high-viscosity and/or excellent clarity is provided. In one embodiment, the granular starch is made cold-water swellable by contact with aqueous alcohol, then derivatized with an .alpha.-halocarboxylic acid, and then isolated under condition which inhibit esterification of the granular starch, e.g. high pH, to afford a starch that has excellent paste clarity. In other embodiments, the cold-water-swellable granular starch is crosslinked to afford a starch that has very high paste viscosity.
摘要:
A regenerated cellulosic product is produced by nitrosating and dissolving a cellulosic material in a solution comprising a dialkylacylamide solvent and adding from 2 to 25% by weight, based on the weight of the solution, of a tertiary amine to form a soluble cellulose nitrite ester, contacting the cellulose ester with a coagulant therefore, stretching the coagulated cellulose ester prior to complete regeneration thereof and then completing the regeneration of the cellulose to produce a regenerated cellulosic product.
摘要:
Cold water soluble methylated, ethylated or carboxymethylated non-gelatinized granular starch materials are provided which are particularly well suited for use as thickeners and/or rheology modifiers in latex paint compositions. Such starch materials have a methyl, ethyl or carboxymethyl degree of substitution (D.S.) of from about 0.15 to about 1 and have a ratio of total inorganic anion content (in weight percent on a starch material dry solids weight basis) to methyl, ethyl or carboxymethyl D.S. of about 14 or less.