Abstract: Compounds of formulae I and IaR--Y--CO--R.sub.3 --CO--O--A (I),R--Y--CO--R.sub.3 --CO--O--CH.sub.2 --A.sub.1 (Ia),whereinR is a radically polymerisable hydrocarbon group,R.sub.3 is a direct bond, linear or branched C.sub.1 -C.sub.22 alkylene, C.sub.3 -C.sub.8 cycloalkylene or C.sub.6 -C.sub.14 arylene,A is the radical, reduced by a hydroxy group in a 2- or 3position, of a cyclic-oligomeric carbohydrate or of a derivative of such a carbohydrate,A.sub.1 is the radical, reduced by a hydroxymethyl group, of a monomeric or linear oligomeric carbohydrate or of a derivative of such a carbohydrate, andY is --O--, --NH-- or --N(C.sub.1 -C.sub.6 alkyl)-.Homo- and co-polymers having those monomers have, depending upon their composition, hydrophilic, amphiphilic or hydrophobic properties and are able to form hydrogels. The polymers can be used, for example, as surfactants, thickeners, carriers for biologically active ingredients or in the manufacture of contact lenses.

Abstract: A plasticized cellulose acetate is described with a content of a modified cellulose acetate A comprising a grafted oligomer of a cyclic ester, in particular in the form of .epsilon.-caprolactone, which comprises additionally a plasticizing agent in the form of an oligomer B of a cyclic ester, and the terminal carboxyl group of the oligomer is esterified with an alcohol or an alcohol derivative having at least one free hydroxyl group, with a boiling point of at least approximately 120.degree. C. and a melting point of no more than approximately 180.degree. C. and the ratio of weight of component A to B is represented by the formula (I)0.3.ltoreq.A/(A+B).ltoreq.0.95 (I).This plasticized cellulose acetate can be produced advantageously for example when an oligomer B in the form of the reaction product of a cyclic ester, in particular in the form of .epsilon.

Abstract: The composition comprising a cellulose ester including at least 10 weight % of a low-substituted cellulose ester having an average degree of substitution not exceeding 2.15 and giving a 4-week decomposition rate of at least 60 weight % as determined using the amount of evolution of carbon dioxide as an indicator in accordance with ASTM 125209-91. The composition may contains a plasticizer, an aliphatic polyester, a photolysis accelerator such as anatase type titanium dioxide or a biodegradation accelerator such as organic acids and their esters. The low-substituted cellulose ester may be a cellulose ester having an average degree of polymerization from 50 to 250, an average degree of substitution from 1.0 to 2.15 and a residual alkali metal/alkaline earth metal-to-residual sulfuric acid equivalent ratio of 0.1 to 1.1. The biodegradable cellulose ester composition is suitable for the manufacture of various articles including fibrous articles such as tobacco filters.

Abstract: There are described filaments on the basis of a cellulose acetate soluble in acetone, the degree of polymerization (DP) of the cellulose acetate being between about 110 and 210 and the degree of substitution (DS) preferably between about 2.2 and 2.7. Optically isotropic spinning solutions can be obtained, the cellulose acetate concentration of which is about 35 to 47 mass-%. When such an optically isotropic spinning solution is spun, in particular by dry spinning, filaments are obtained in a profitable manner because the costs connected with the recovery of the acetone can be appreciably lowered, without impairing the desirable properties of the filaments, which are suitable in particular for the production of cigarette filter tow.

Abstract: A filter tow of cellulose acetate filaments and/or cellulose acetate staple fibers, has at least the surface of the filaments and staple fibers consisting of a cellulose acetate having an acetyl number of less than 53%, preferably less than 49%. The method for the manufacture of the filter tow comprises the spinning of cellulose acetate filaments from a solution of cellulose acetate having an acetyl number of at least 53% in acetone, if necessary, cutting the filaments into staple fibers, and combining the filaments and/or staple fibers to a filter tow, the filaments or staple fibers being hydrolyzed so that at least the cellulose acetate at the surface of the filaments and staple fibers has an acetyl number of less than 53%, preferably less than 49%. The invention involves also a tobacco smoke filter element made from the filter tow, as well as a method for the manufacture of the tobacco smoke filter element.

Abstract: Water soluble or water-dispersible cellulose acetoacetate esters are prepared by contacting a cellulose material with diketene, an alkyl acetoacetate, 2,2,6-trimethyl-4H-1,3-dioxin-4-one or a mixture thereof and a carboxylic anhydride in a solvent system comprising lithium chloride plus a carboxamide. Compositions containing the cellulose acetoacetate esters are useful for coatings applications.

Abstract: A novel method has been discovered for the pretreatment of cellulose with acetic acid and acetic anhydride under pressure, resulting in uniformly activated cellulose fibers. The improved process for producing cellulose diacetate comprises the steps of: (1) pretreating and activating the fluffed cellulose fibers in a solution of glacial acetic acid and acetic anhydride at room temperature and elevated pressure for a specific time; (2) mixing the activated cellulose containing acetic acid and anhydride further with a mixture of glacial acetic acid, acetic anhydride and sulphuric acid catalyst and acetylating the cellulose at specific initial and end temperatures to form primary cellulose acetate; and (3) partially neutralizing the sulphuric acid catalyst and destroying the excess acetic anhydride by adding an aqueous solution of magnesium acetate with dilute acetic acid to provide an excess of water in the reaction dope for hydrolysis at elevated temperature and pressure conditions.

Abstract: Disclosed is a process comprising continuously flowing a composition through a hydrolysis zone so as to achieve a residence time distribution such that at least 81% of the area under the residence time distribution curve is within plus or minus 50% of the mean residence time. The composition comprises cellulose triacetate in the range of 5 to 30%, water in the range of 4 to 25%, and acetic acid in the range of 45 to 91%.

Abstract: The present invention relates to a coating compound for sheets, films, or molded products composed of modified or unmodified polysaccharides.

Abstract: A process for recycling waste from the manufacture filtered cigarettes is disclosed herein. The process comprises the following steps: A waste stream from the manufacture of filtered cigarettes is provided. The waste stream includes tobacco, cellulose ester polymer, and paper. A substantial portion of the cellulose ester polymer is separated from this waste stream. This cellulose ester polymer is contacted with a sufficient volumne of fluid to extract contaminants therefrom. The fluid is under pressure and temperature conditions, such that the fluid is a supercritical or a near supercritical fluid.

Abstract: An improved process for the production of cellulose ester fibrets wherein a thickened slurry of the fibrets in a liquid mixture of a solvent for the fibrets and a fibret non-solvent is contacted with saturated steam in the separation of the solvent from the fibrets.

Abstract: Provided is a novel improved process for the preparation of .alpha.-D-cellobiose octaacetate via the acetylative degradation of cellulose or cellulose acetate. The title compound is provided in high yield and quality in a facile one-pot process, amenable to large-scale synthesis.

Abstract: Water soluble cellulose acetoacetates prepared by contacting a cellulose material with diketene, an alkyl acetoacetate, 2,2,6-trimethyl-4H-1,3-dioxin-4-one or a mixture thereof in a solvent system comprising lithium chloride plus a carboxamide. Compositions containing the cellulose acetoacetates and, optionally, a crosslinking agent are useful for coatings applications.

Abstract: A method and composition are provided for making biodegradable injection ded parts from 30% to 70% cellulose acetate, 10% to 60% unmodified raw (whole) starch and 5% to 35% plasticizer including glycerols and glycerol acetates. Other ingredients that can be used include: starch, flour and paper acetates; gelatin; boric acid; and agricultural fillers. The solid ingredients are combined and fed to an extruder used to make pellets or to feed injection molding equipment. The resulting parts are clear to white or colorful depending upon the added filler materials. The plastics formed are water resistant, high strength and biodegradable.

Abstract: A method is provided for preparing a cellulose ester plastic composition from waste paper (e.g. recycled paper) and/or sugar cane bagasse. The paper or bagasse is reacted with an acid anhydride in the presence of a catalyst to esterify some of the hydroxy groups on the cellulose. The resulting cellulose ester product is combined with various additives such as acetins, agricultural fillers, and carbon particles.

Abstract: An assay for an analyte wherein sample is applied to a support capable of binding proteins by essentially only hydrogen bonding and fixed on the support. Analyte may be determined on the support by use of a suitable tracer. A preferred support is amphiphilic cellulose acetate. In an immunoassay, it is possible to determine analyte without use of a supported ("capture") antibody.

Abstract: Disclosed is a novel process of preparing tobacco smoke filter material, wherein an acidic compound such as citric acid is dissolved in a cellulose acetate spinning solution (dope) prior to spinning the filaments of the filter material.

Abstract: Process for reducing the degree of substitution of cellulose esters employing Lewis acids as solvolysis promoters is disclosed. Novel low degree of substitution cellulose esters produced by the invention process are also described.

Abstract: A process for making cellulose acetate from wood pulp takes wet wood pulp and instead of converting it into dry pulp sheet which is the usual feedstock for acetate, dries and mechanically separates the pulp into a cellulose flock using a pin mill through which a hot drying gas is passed. Deactivation of the cellulose is avoided by control of the drying gas exit temperature to 80.degree. C. to 95.degree. C. and of the moisture content of the cellulose flock to 4 to 15% by weight. The flock produced may be acetylated directly without any need for reactivation treatments additional to the normal activation with acetic acid.

Abstract: A modified cellulose and/or chitin for biocompatible dialysis membranes having a structure represented by the formula ##STR1## wherein cell is cellulose or chitin, in each case without hydroxyl groups, s=3 in the case of cellulose and s=2 in the case of chitin, R' is CH.sub.3 and/or C.sub.2 H.sub.5 and/or C.sub.3 H.sub.7, X denotes specified functional groups, R" is H or R, R"' denotes R, x+t=0.75 to 2.85, t=0 to 2.85, x=0 to 2.85, and r=0 to 1. A process for preparation of the cellulose and/or chitin derivatives is also disclosed.

Abstract: A modified cellulose and/or chitin for biocompatible dialysis membranes having a structure represented by the formula ##STR1## wherein cell is unmodified cellulose or chitin, in each case without hydroxyl groups, s=3 in the case of cellulose and s=2 in the case of chitin, R' is CH.sub.3 and/or C.sub.2 H.sub.5 and/or C.sub.3 H.sub.7, X denotes specified functional groups, m=0.75 to 2.85, and x=0.005 to 2.10. A process for preparation of the cellulose and/or chitin derivatives is also disclosed.

Abstract: A modified cellulose and/or chitin for biocompatible dialysis membranes having a structure represented by the formula ##STR1## wherein Cell is cellulose or chitin, in each case without hydroxyl groups, s=3 in the case of cellulose and s=2 in the case of chitin, R' is CH.sub.3 and/or C.sub.2 H.sub.5 and/or C.sub.3 H.sub.7, X denotes specified functional groups, R" is H or R, Z corresponds to the following groups of atoms: SR", SO.sub.3 H and salts thereof, SO-R, SONR".sub.2, SO.sub.2 -R, SO.sub.2 NR".sub.2, SO.sub.2 H and salts thereof, F, Cl, Br, I, NR".sub.2, PR".sub.2, PO.sub.3 H.sub.2 and salts thereof, PO.sub.2 H(OR), PO(OR).sub.2, PO.sub.2 HR" and salts thereof, POR"(OR) and POR".sub.2, x+t=0.75 to 2.85, t=0 to 2.85, x=0 to 2.85, and z=0.01 to 0.45. A process for preparation of the cellulose and/or chitin derivatives is also disclosed.

Abstract: A separation agent essentially comprises an aliphatic or aromatic ester of a polysaccharide, except for cellulose acetate and an aromatic ester of cellulose. It is useful for separation of various chemical substances, especially optical resolution of optical isomers.

Abstract: A process for the production of cellulose ester fibrets wherein a solution of the cellulose ester is contacted with a non-solvent for the cellulose ester in a precipitation zone under shearing conditions, and a solvent-nonsolvent mixture is separated from the formed fibrets and recycled to the precipitation zone.

Abstract: Cellulose ester microparticles with unique properties are made by a process having the following steps:(a) dissolving a cellulose ester in a liquid comprising a solvent for the cellulose ester and a non-solvent for the cellulose ester, thereby forming a dope;(b) spheronizing the dope thereby forming fine droplets of the dope;(c) dropping the droplets for a finite amount of time; and(d) precipitating the droplets in a bath containing a precipitant.

Abstract: A separation agent essentially comprises an aliphatic or aromatic ester of a polysaccharide, except for cellulose acetate and an aromatic ester of cellulose. It is useful for separation of various chemical substances, especially optical resolution of optical isomers.

Abstract: Cellulosic sheet material is processed in preparation for esterification for example acetylation to produce cellulose acetate, by treating the sheet material with water and then feeding the wetted material into a machine that simultaneously shreds and dries the material. The conditions in the machine are carefully controlled (outlet temperature not in excess of 110.degree. C. and moisture content 4-15% by weight) to ensure that the cellulosic material does not become deactivated towards esterification. The method enables low alpha content cellulosic material supplied in the form of high density sheet to be acetylated to produce high quality cellulose acetate flake.

Abstract: Cellulose derivatives are disclosed which have the following formula: ##STR1## wherein Z is selected from the group consisting of alkylene, alkenylene, alkynylene, cycloalkylene or benzylene or xylylene radicals, which may or may not be substituted;X is selected from the group consisting of --H, --NR.sub.2, --N.sup.+ R.sub.3, --CN, --COOH, --SO.sub.3 H, --SO.sub.3 H, --PO(OR).sub.2, CONR.sub.2 or --Si(OR).sub.3 ;R is selected from the group consisting of hydrogen, alkyl and alkenyl groups having from 1 to 25 carbon atoms, and cycloalkyl, tolyl and phenyl groups;Y is selected from the group consisting of alkyl, alkenyl, alkynyl groups having from 1 to 36 carbon atoms, which may or may not be substituted, cycloalkyl, phenyl, tolyl and benzyl groups, ##STR2## (--CH.dbd.CH--COOH), and NHR, where R has the same meaning as in X, andm=0 to 2.5n=0.01 to 2.95,with the provision that, when m=0, n.gtoreq.1.55, if Y is an alkyl radical with 1 to 5 carbon atoms, 3-(CH.sub.2).sub.

Abstract: A modified cellulose for biocompatible dialysis membranes having a structure represented by the formula ##STR1## wherein cell is cellulose or chitin, in each case without hydroxyl groups, s=3 in the case of cellulose and s=2 in the case of chitin, R' is CH.sub.3 and/or C.sub.2 H.sub.5 and/or C.sub.3 H.sub.7, X denotes specified functional groups, R" is H or R, R"' denotes R, x+t=0.75 to 2.85, t=0 to 2.85, x=0 to 2.85, and r=0 to 1. A process for preparation of the cellulose derivatives is also disclosed.

Abstract: Water soluble cellulose acetate composition having improved processability and tensile properties suitable for application as films, coatings and fibers and comprising one or more lower molecular weight water soluble cellulose acetate components and one or more higher molecular weight water soluble cellulose acetate components, and wherein the lower molecular weight water soluble cellulose acetate components have solution viscosities at least 20 percent of that of the higher molecular weight water soluble cellulose acetate components. An exemplary composition comprises from about 85 to 98 percent by weight of a lower molecular weight water soluble cellulose acetate component having a solution viscosity of form about 5 to 50 cps and from about 15 to 2 percent by weight of a higher molecular weight water soluble cellulose acetate component having a solution viscosity of greater than 100 cps.

Abstract: A modified cellulose for biocompatible dialysis membranes having a structure represented by the formula ##STR1## wherein Cell is cellulose or chitin, in each case without hydroxyl groups, s=3 in the case of cellulose and s=2 in the case of chitin, R' is CH.sub.3 and/or C.sub.2 H.sub.5 and/or C.sub.3 H.sub.7, X denotes specified functional groups, R" is H or R, Z corresponds to the following groups of atoms: SR", SO.sub.3 H and salts thereof, SO-R, SONR".sub.2, SO.sub.2 -R, SO.sub.2 NR".sub.2, SO.sub.2 H and salts thereof, F, Cl, Br, I, NR".sub.2, PR".sub.2, PO.sub.3 H.sub.2 and salts thereof, PO.sub.2 H(OR), PO(OR).sub.2, PO.sub.2 HR" and salts thereof, POR"(OR) and POR".sub.2, x+t=0.75 to 2.85, t=0 to 2.85, x=0 to 2.85, and z=0.01 to 0.45. A process for preparation of the cellulose derivatives is also disclosed.

Abstract: A modified cellulose for biocompatible dialysis membranes having a structure represented by the formula ##STR1## wherein cell is unmodified cellulose or chitin, in each case without hydroxyl groups, s=3 in the case of cellulose and s=2 in the case of chitin, R' is CH.sub.3 and/or C.sub.2 H.sub.5 and/or C.sub.3 H.sub.7, X denotes specified functional groups, m=0.75 to 2.85, and x=0.005 to 2.10. A process for preparation of the cellulose derivatives is also disclosed.

Abstract: A release agent comprising a polyfunctional alkoxysiloxane and an organic compound which is solid at room temperature and contains a functional group capable of reacting with said polyfunctional alkoxysiloxane, and a composite material comprising a substrate and a cured film of the release agent are disclosed. The cured film of the release agent exhibits high strength and excellent release properties without causing blocking or contamination on an adherent.

Abstract: A regenerable support matrix useful for immobilization of biologically active materials is prepared by coating a core support with a cellulose ester, removing ester groups by hydrolysis to produce hydroxyl groups and converting the hydroxyl groups to dialkylaminoalkyl ether groups. The support matrix can immobilize biologically active proteinaceous materials with a net negative charge by adsorption. The support matrix is readily regenerated when an immobilized biologically active material becomes inactive by washing the support with a base or salt solution and adsorbing additional biologically active material to the support. Multiple cycles of immobilization and regeneration are possible without significant deleterious affects.

Abstract: A method to selectively oxidize a polyglucose, on the oxygen of the hydroxy groups of the C-6 position of the glucose rings, while substantially maintaining the degree of polymerization of the polyglycosidic units, comprising heating a 6-sulfonyl polyglucose, for instance 6-O-para-(P)-toluene sulfonyl polyglucose with dimethyl sulfoxide (DMSO) in the presence of at least a catalytic amount of a catalyst selected from a member of the group consisting of: symmetrical--collidine, sodium bicarbonate and pyridine, to produce a polyglucose having aldehyde groups on the oxygen of the hydroxyl on the C-6 position of the glucose rings. In a preferred embodiment when pyridine is selected, this method enables use of that reaction to obtain other new products having other functional groups, mainly on the C-6 position of the glucose rings, without having to purify the aldehyde which may serve as intermediate.

Abstract: Microparticle of cellulose acetate and derivatives thereof characterized by being water soluble, having a large interior void space and having a plurality of open exterior surface pores. These water soluble microparticles can be loaded with a chemical selected from the group consisting of pharmaceuticals, dyes, flavorings, agriculturals, solid catalysts and fragrances.

Abstract: A method is provided for treating and modifying solid, high molecular weight Lewis base polymers, particularly shaped structures such as fibers, filaments or knitted fabrics, to form branched polymer with improved electrical conductivity, water absorbency and dye receptivity while retaining the essential structural shape. The method comprises heating the polymer in the presence of an aqueous treating solution containing an ethylenically unsaturated monomer which does not readily polymerize under the conditions of treatment and a catalyst which is a source of hydrogen ions or protons. The treatment is carried out at a temperature and for a sufficient time so as to effect essentially single molecule addition of the monomer pendent to the polymer chain with substantially no graft polymerization of the monomer to the polymer. A particularly preferred embodiment of the method is the treatment of nylon 6,6 knitted fabric with an aqueous solution of acrylamide and hydrochloric acid for about one hour at 95.degree.

Abstract: The preparation of microcrystalline triacetylcellulose by acid-catalyzed acetylation of microcrystalline cellulose, perfluoroalkanesulfonic acids with 1 to 8 carbon atoms are used as the catalyst, resulting in a non-hazardous process and high yields of exceptionally high purity product, the latter being particularly suitable for chromatographic purposes, in particular for the chromatographic resolution of racemates.

Abstract: A porous cellulose acetate molding containing an odoriferous substance is provided which is prepared by incorporating an odoriferous substance in a porous molding comprising cellulose acetate having a combined acetic acid of 50 to 58%, a pore volume of at least 0.65 cc/g and a collapsing strength of at least 10 kg. Said porous cellulose acetate may be one which is surface-saponified. Examples of the odoriferous substances include volatile substances such as insect repellents, antibacterials and mold inhibitors. Said porous cellulose acetate molding can adsorb the odoriferous substances fully without substantially changing its shape and persistently volatilize the substance for a long time.

Abstract: Cellulose acetate is effectively prepared from cellulose and acetic anhydride in a solvent of acetic acid in the presence of a catalyst of sulfuric acid, when the reaction system is being evacuated at least before the reaction mixture reaches a boiling point thereof until the reaction completes, so that the vapor evolved from the reaction mixture may be condensed to distill off and the reaction product may be concentrated.

Abstract: A method is provided for treating and modifying solid, high molecular weight Lewis base polymers, particularly shaped structures such as fibers, filaments or knitted fabrics, to form branched polymer with improved electrical conductivity, water absorbency and dye receptivity while retaining the essential structural shape. The method comprises heating the polymer in the presence of an aqueous treating solution containing an ethylenically unsaturated monomer which does not readily polymerize under the conditions of treatment and a catalyst which is a source of hydrogen ions or protons. The treatment is carried out at a temperature and for a sufficient time so as to effect essentially single molecule addition of the monomer pendent to the polymer chain with substantially no graft polymerization of the monomer to the polymer. A particularly preferred embodiment of the method is the treatment of nylon 6,6 knitted fabric with an aqueous solution of acrylamide and hydrochloric acid for about one hour at 95.degree.

Abstract: A new class of compounds, perfluoroacyl modified cellulose acetate polymers, has been synthesized. A novel method of preparation of these compounds is shown. It was discovered that these polymers can be used to form membranes having superior characteristics. The perfluoroacyl modification allows these polymers to be cast as ultrathin membranes resulting in improved gas flux rates while maintaining a high degree of selectivity, improved resistance to water, and the elimination of post treatment procedures. Furthermore these polymers can be spun as hollow fibers.

Abstract: The invention refers to water-insoluble fibers of cellulose acetate cellulose propionate and cellulose butyrate with an extremely high absorptive capacity for water and physiological liquids and to a process for their preparation.

Abstract: High strength, high modulus cellulose triacetate fibers are produced by spinning a 30-42% by weight solution of cellulose triacetate having an acetyl content of at least 42.5% and an inherent viscosity of at least 5 from a solvent mixture comprising trifluoroacetic acid and another solvent having a molecular weight of less than 160 in a mol ratio of 0.3-3.0 through an air gap into a coagulating bath. The fibers are optionally heat treated under tension or saponified to provide high strength high modulus regenerated cellulose fibers.

Abstract: The present invention relates to a method of preparing lower fatty acid esters of cellulose which comprises esterifying at a temperature of between about 75.degree. C. and about 110.degree. C. a cellulose compound having esterifiable hydroxyl groups with an esterifying bath comprising an organic acid anhydride, a diluent, and a catalyst comprising from 0.2 to 2.0 parts phosphoric acid, from 0.1 to 1.2 parts sulfuric acid, and from 0.05 to 0.6 parts of a hindered aliphatic alcohol by weight per 100 parts of the cellulose to be esterified.

Abstract: A process for producing cellulose diacetate is disclosed which comprises the steps of:(a) pretreating and activating 100 parts by weight of cellulose, adding a mixture of 200 to 400 parts of acetic anhydride, 0 to 350 parts of glacial acetic acid, and 0.5 to 5 parts of acid catalyst, heating the reactants to a temperature from 50.degree. C. to 85.degree. C. at approximately a constant rate, maintaining this temperature for 3 to 20 minutes, thereby acetylating cellulose to form primary cellulose acetate;(b) neutralizing the acid catalyst in the reaction mixture containing primary cellulose acetate obtained in step (a), introducing steam under pressure into the system to change the temperature of the system to 125.degree. C. to 170.degree. C., and maintaining this temperature for 30 minutes to 6 hours, thereby hydrolyzing the primary cellulose acetate to accomplish ripening; and(c) flashing the ripened reaction mixture at a temperature of 125.degree. C. to 170.degree. C.

Abstract: Heat treatment of never-dried dissolving pulps prior to drying prevents or retards the hornification and consequent decrease in esterification reactivity which normally occurs on drying of untreated pulps.

Abstract: Disclosed is a catalyst and a method of preparing lower fatty acid esters of cellulose which comprises esterifying at a temperature of between about 75.degree. C. and about 110.degree. C. a cellulose compound having esterifiable hydroxyl groups with an esterifying bath comprising an organic acid anhydride, a diluent, and a catalyst comprising (a) from about 0.3 to about 3.0% by weight, based on the weight of cellulose, of an acid selected from the group consisting of sulfuric acid, p-toluene sulfonic acid, methane sulfonic acid, methane disulfonic acid and m-benzene disulfonic acid, and (b) from about 0.05 to about 0.3% by weight, based on the weight of cellulose, of a dialkyl phosphite, the alkyl groups of which contain from 2 to 4 carbon atoms, the weight ratio of said bath to the cellulose being between about 5:1 and about 10:1.

Abstract: Disclosed is a method of preparing lower fatty acid esters of cellulose which comprises esterifying at a temperature of between about 75.degree. C. and about 110.degree. C. a cellulose compound having esterifiable hydroxyl groups with an esterifying bath comprising an organic acid anhydride, a diluent, and from about 0.3% to about 3.0% by weight, based on the weight of cellulose, of a catalyst selected from p-toluene sulfonic acid, methane sulfonic acid, methane disulfonic acid or m-benzene disulfonic acid.

Abstract: Disclosed is a catalyst composition and a method of preparing lower fatty acid esters of cellulose which comprises esterifying at a temperature of between about 75.degree. C. and about 110.degree. C. a cellulose compound having esterifiable hydroxyl groups with an esterifying bath comprising an organic acid anhydride, a diluent, and a catalyst comprising from about 25 to about 75% by weight sulfuric acid and about 75 to about 25% by weight phosphoric acid, the catalyst being used in amounts of from about 0.3 to about 0.8% by weight based on the weight of cellulose.