Patent GB-1055086-A (GB)
Title: Production of spray dried decausticized polymeric alcohol xanthates
IPC: C08J3/12
Filed: 1965-08-23
Abstract: An alkaline solution of a polymeric alcohol xanthate is decausticized to a pH less than 13 and then spray-dried to produce a stable, powdered, polymeric alcohol xanthate product. The solution treated may be viscose, amylose xanthate, polyvinyl alcohol xanthate or polyallyl alcohol xanthate, and the solution may be decausticized by dialysis, neutralization with weak acid, ion-exchange (using anion-exchange or cation exchange materials) or ion-retardation. The solution may be spray dried under conditions of temperature and air velocity (e.g. into high velocity gas at at least 38 DEG  C.) sufficient to produce a powdered product which is substantially dry, free of alkali contaminants, has a pH less than 13 when dispersed at 1% concentration in water and has a degree of substitution of at least 3%.  The degree of substitution is defined as the percentage of available groups capable of substitution which are in fact substituted with the xanthate radical. An inert extender material, e.g. a pigment, a sizing agent, a clay size, or a solid reactive material rendered active upon dissolution of the mixture may be added to the solution to be spray-dried.  In examples:  (A) Viscose.-(1) a viscose solution is decausticized by dialysis and spray-dried.  (2) Viscose is decausticized by dialysis, using an acid form cation exchange resin to maintain a high concentration gradient through the dialysis membrane to reduce the quantities of water required for the dialysis, and then spray-dried. (6) to (9) Viscose is decausticized by the use of ion-exchange resins and spray-dried. (10) Viscose is decausticized using acid-treated bast fibres as an ion-exchange material.  (11), (12) and (16) Viscose is decausticized using ion-exchange resins and spray-dried.  (17) Viscose is decausticized using an ion-retardation resin. (19) Viscose is decausticized using a liquid ion-exchange medium and spray-dried.  (21) and (22). Viscose is decausticized by dialysis, followed by treatment with an ion-exchange resin.  (23) Viscose is decausticized by treatment with an anion-exchange resin, followed by treatment with a cation-exchange resin, and spray-dried.  (24) Viscose is decausticized by treatment with a cation-exchange resin, followed by treatment with an anion exchange resin, and spray-dried.  (25) Viscose is decausticized by treatment with a mixed-bed ion-exchange resin. (37) (a) Decausticized viscose is added to untreated viscose to form a spinning solution; (b) a dilute viscose solution is decausticized, spray-dried and the powder redissolved to form a spinning solution.  (38) Cellulose derivatives are made by: (a) extruding a decausticized viscose solution, or solution reconstituted from the spray-dried product, as a film or fibre into a solution of an isocyanate or a polyether having isocynate end groups; (b) pouring a mixture of phenyl isocyanate, carbon tetrachloride, and a wetting agent into a viscose solution, adjusting the pH of the emulsion to 4.5 with acetic acid, standing at 25 DEG  C. for 72 hours and recovering the derivative in the form of a white gel from the surface of the aqueous layer; (c) a 1% solution of adipoyl chloride in carbon tetrachloride is added to a viscose solution and the pH adjusted to 4.0 to obtain a cross-linked cellulose derivative.  (42) A decausticized viscose solution is used as an interfacial reactant to form cellulose ethers, esters or urethanes from a complementary reactant, e.g. diphenyl methane diisocyanate in an inert immiscible solvent, e.g. toluene.  (53) Ammonium cellulose xanthate is made by passing a solution of decausticized viscose through a cation exchange resin in the ammonium form.  Lithium and potassium cellulose xanthates are made in like manner. (54) Cellulose thiourethanes are made from decausticized viscose by the zinc-amine method of U.S.A. Patent 2,705,231.  (56) Decausticized viscose solution is reacted with chloroacetic acid in aqueous solution to form a cellulose ether or with adipoyl chloride to make a cellulose ester. (61) Decausticized viscose solutions are oxidized to xanthide gels by treatment with hydrogen peroxide, saturated aqueous calcium hypochlorite or iodine-potassium iodide. (78) (a) Dry powders of decausticized viscose are admixed with such materials as masked mono- and di-isocyanates, so that when the material is dissolved in water and coated on paper or when a film is cast from such a solution and dried, it is insolubilized and cross-linked by the isocyanate removed from the masking agent. Materials which may be included are reactive dyes, plasticizers, cationic reagents, emulsifiers, fibres, cross-linking agents, e.g. sodium formaldehyde sulphoxylate, dialdehyde starch, dialdehyde guar gum, peroxides, amines and polyisocyanates. Solid acids or materials which hydrolyse to produce acids, e.g. citric acid, ethyl lactate, and delta-gluconolactone may also be used.  (b) Cellulose xanthate dissolved in a non-aqueous solvent, e.g. ethylene chlorohydrin, or mixtures of ethylene chlorohydrin with water are decausticized and spray dried.  (B) Amylose xanthate.-(3) Amylose xanthate is decausticized by dialysis and spray-dried. (13) and (16) Amylose xanthate is decausticized by treatment with an ion-exchange resin and spray-dried.  (18) Amylose xanthate is decausticized by treatment with an ion-retardation resin and spray-dried.  (20) Amylose xanthate is decausticized by dialysis, followed by treatment with an ion-exchange resin, and spray-dried.  (C) Polyvinyl and polyallyl alcohol xanthates.-(4) Polyvinyl alcohol xanthate is decausticized by dialysis and spray dried. (5) Polyallyl alcohol xanthate is decausticized by dialysis and spray dried.  (14) Polyvinyl alcohol xanthate is decausticized by treatment with an ion-exchange resin and spray-dried.  (15) Polyallyl alcohol xanthate solution is decausticized by treatment with an ion-exchange resin and spray-dried.  (16) Polyvinyl alcohol xanthate solution and polyallyl xanthate solution are decausticized by treatment with an ionexchange resin and spray-dried.  (D) Graft polymers.-(41) Hexamethylene diamine and decausticized viscose are mixed and contacted with a carbon tetrachloride solution of adipoyl chloride to obtain a dispersion of nylon and nylon-cellulose graft polymers.  (E) Cellulose derivative compositions.-A decausticized viscose in the form of a spray-dried, powdered product is dissolved in water, carbon black added and the dispersion mixed to form a black ink suitable for printing on regenerated cellulose surfaces, the ink being cured by heating.ALSO:A decausticized cellulose xanthate solution is mixed with a natural or synthetic zeolite in finely divided form and extruded in the form of fibres or films which can be formed into cigarette filters.ALSO:Alkaline solutions of polymeric alcohol xanthates (e.g viscose, amylose xanthate, polyvinyl alcohol xanthate and polyallyl alcohol xanthate) are decausticized to pH less than 13 and spray-dried to produce a stable powdered product which is dissolved in water to form a solution useful in treating textiles, making non-woven fabrics and paper.  In Examples: (32) A solution made by dissolving in water a powder obtained by spray-drying vicose decausticized by cation exchange to pH 9, and having a 0.5% cellulose content, is used for sizing cotton fabric.  Cotton muslin sheeting is dipped into the solution at 25 DEG C., allowed to drain, and either air-dried or heated to 80 DEG C.  The sized cotton has a substantially crisper feel than coated pieces.  (51) Decausticized viscose solutions are used to coat nylon fibres to produce composite fibres having a regenerated cellulose coating. The resulting product gives better dispersion of fibres in viscose and good matrix fibre adhesion in the formation of non-woven webs. Woven fabrics of such fibres have enhanced moisture absorbency. (57) Decausticized viscose solutions are used as binders in the formation of non-woven textiles. Bats of glass, mylar (Trade Mark), nylon, and cellulose acetate fibres may be thus impregnated and pressed or cured to form a non-woven fabric.  29) A cellulose impregnated high wet strength paper is made by impregnating a long fibre hemp tissue paper with decausticized viscose (or amylose xanthate) and regenerating by thermal or acid treatment.  The paper may be formed into tubes and impregnated with the viscose solution, and the impregnated tubing passed through an acid regenerating bath (34) A decausticized viscose solution is mixed with an ion-exchange resin, tissue paper dipped in the resulting slurry, drained and dried to form an ion-exchange membrane.  (46) Decausticized viscose solution is mixed with paper pulp in the formation of paper to promote exhaustion of basic resins on to the paper.  The dacausticized viscose can also be used as a beater additive in a paper machine.  Upon regeneration, the cellulose acts as a binder for the resin and the paper.  (52) Decausticized viscose solutions are used to coat synthetic fibres e.g. of nylon or Dacron (Trade Mark) to be incorporated in the formation of synthetic papers.  Such solutions may also be used as binders for such papers. (61) Decausticized viscose powder is mixed with wood pulp and treated with iodine or a hypochlorite or peroxide, thereby oxidising the xanthates to xanthides which function as wet and dry strength sizes for the paper made from the pulp.  (62) Partially insoluble (but swellable) powders made by spray drying decausticized viscose are added as an aqueous dispersion to the fibre suspension at the wet end of a paper machine.  These xanthates can then be precipitated on to the fibres by oxidation to the xanthides as in (61) or by precipitation as a zinc salt. Solutions of decausticized viscose may be similarly treated.  (63) Spray-dried decausticized viscose powders are used in making high wet strength papers suitable as tea bags or meat casings.  A paper finish contai