摘要:
The disclosure describes a process for the preparation of regenerated cellulose filaments from an anisotropic solution including cellulose formate, phosphoric acid, and formic acid in which the formed cellulose formate filaments are dried to a moisture content of not more than 15% prior to regeneration and after regeneration the filaments are washed and dried under low tension. In this manner cellulose multifilament yarns of high breaking load and high elongation at break can be obtained, which in addition have a very regular linear density.
摘要:
An optically anisotropic solution containing cellulose and inorganic acids of phosphorus contains 94-100 wt % of the following constituents: cellulose; phosphoric acid and/or its anhydrides; and water; and 0-6 wt % of other constituents. This solution can be prepared in an apparatus in which intensive mixing is made possible by the shearing forces generated by mixers and kneaders in the apparatus. The solution can be used in making pulp, hollow fibres, staple fibre, membranes, nonwovens, or films.
摘要:
An optically anisotropic solution containing cellulose and inorganic acids of phosphorus contains 94-100 wt % of the following constituents: cellulose; phosphoric acid and/or its anhydrides; and water; and 0-6 wt % of other constituents. This solution can be prepared in an apparatus in which intensive mixing is made possible by the shearing forces generated by mixers and kneaders in the apparatus. The solution can be used in making pulp, hollow fibres, staple fibre, membranes, nonwovens, or films.
摘要:
Process for preparing a solution of cellulose formate from cellulose plates, in particular high-density plates, without prior mechanical destruction of these plates. The plates are dissolved directly, by means of an impregnating step of the whole plates in a base liquid of formic acid, followed by an operation of kneading of the plates thus impregnated in contact with both formic acid and phosphoric acid. The process is preferably carried out in order to prepare ready-for-spinning solutions with, in particular, if necessary, an intermediate operation of adjustment of the final composition. Solutions prepared using such a process. Preparation of objects made of cellulose, starting with these solutions, in particular fibers or films. Assemblies of such fibers or films. Articles reinforced with such fibers or films or assemblies, these reinforced articles being especially tires.
摘要:
A graphene ribbon fiber manufacturing process, where a coagulation medium flows in the same direction as the graphene ribbon fibers. The process for spinning graphene ribbon fibers starts with unzipping carbon nanotubes to form graphene ribbons, purifying and drying the graphene ribbons and subsequent dissolving of the graphene ribbons in a suitable solvent, preferably a super acid to form a spin-dope. The spin-dope is spun such that the accrued fibers are guided into a coagulation medium, also known as anti-solvent, where the spun or accrued fibers are coagulated. The coagulated graphene ribbon fibers are stripped, neutralized and washed and wound on bobbins.
摘要:
A method for dissolving an aramid polymer in sulfuric acid using a double shaft kneader, comprising the steps: dosing the polymer and the solvent into the kneader, mixing the polymer and the solvent to dissolve the polymer in the solvent for obtaining a solution, degassing the solution to obtain a spin dope, and transporting the spin dope out of the kneader, wherein the polymer is an aramid polymer and the solvent is sulfuric acid, and whereby the aramid polymer is dosed into the kneader prior to dosing the sulfuric acid into the kneader.
摘要:
A graphene ribbon fiber manufacturing process, where a coagulation medium flows in the same direction as the graphene ribbon fibers. The process for spinning graphene ribbon fibers starts with unzipping carbon nanotubes to form graphene ribbons, purifying and drying the graphene ribbons and subsequent dissolving of the graphene ribbons in a suitable solvent, preferably a super acid to form a spin-dope. The spin-dope is spun such that the accrued fibers are guided into a coagulation medium, also known as anti-solvent, where the spun or accrued fibers are coagulated. The coagulated graphene ribbon fibers are stripped, neutralized and washed and wound on bobbins.
摘要:
A method for dissolving an aramid polymer in sulfuric acid using a double shaft kneader, comprising the steps: dosing the polymer and the solvent into the kneader, mixing the polymer and the solvent to dissolve the polymer in the solvent for obtaining a solution, degassing the solution to obtain a spin dope, and transporting the spin dope out of the kneader, wherein the polymer is an aramid polymer and the solvent is sulfuric acid, and whereby the aramid polymer is dosed into the kneader prior to dosing the sulfuric acid into the kneader.
摘要:
Described is a method for dissolving PPTA or copolymers thereof in sulfuric acid using a twin screw extruder having transporting, mixing, and kneading elements with an entering zone, an intermediate zone, a mixing zone, a negative transport zone, a degassing zone, and a pressure build-up zone. The method includes transporting PPTA or copolymer thereof into the entering zone at a transport capacity low enough as to prevent sulfuric acid entering the entering zone; introducing sulfuric acid in the intermediate zone; essentially fully filling the mixing zone to allow sufficient time to mix and dissolve PPTA or copolymer thereof in the sulfuric acid to obtain a PPTA or copolymer-sulfuric acid solution; creating after the mixing zone a negative transport zone to obtain a product lock between the mixing zone and the degassing zone; creating a thin film of the PPTA or copolymer-sulfuric acid solution in the degassing zone to degas the solution; and entering the solution into the output pressure build-up zone to partially fill this zone and to leave the twin screw extruder.