EP1773887A1

EP1773887A1 - Method for producing cellulose derivatives which contain amino groups, and their use in cosmetic preparations, treating water treatment and in the manufacturing of paper

Info

Publication number: EP1773887A1
Application number: EP05774145A
Authority: EP
Inventors: Jürgen Engelhardt; Meinolf Brackhagen; Klaus Nachtkamp; Wolfgang Koch; Thomas Schulze; Frank Meister
Original assignee: Wolff Cellulosics GmbH and Co KG
Current assignee: Dow Global Technologies LLC
Priority date: 2004-07-23
Filing date: 2005-07-12
Publication date: 2007-04-18
Also published as: DE102004035869A1; JP2008507602A; KR20070039598A; US20060041117A1; CN101027324A; WO2006010468A1; TW200619229A

Abstract

The invention relates to a method for producing cellulose derivatives containing amino groups by reacting alkalized cellulose or alkalized cellulose derivatives with reagents of general formula X-(CH2)n-NR1R2 in which: X represents a leaving group, preferably chlorine, bromine, iodine or a sulfonic acid radical R'SO3, R' representing an aromatic or aliphatic radical with 1 - 24 C atoms, e.g. para-toluyl or methyl; n must be at least 2; radicals R1 and R2, independent of one another, represent aliphatic or branched or cyclic alkyl substituents or aryl substituents with 1 - 24 C atoms, these substituents being optionally substituted by heteroatoms, or represent H, or two radicals R1 and R2, together with the nitrogen, can form a ring. The invention is characterized in that water is used as a reaction medium, and the ratio of cellulose to water ranges from 1: 5 to 1: 40 mol per mol of anhydroglucose unit (AGU). The invention also relates to cellulose derivatives containing amino groups with a specified total substitution and to the use thereof in cosmetic formulations, in treating water or in the manufacturing of paper.

Description

Process for the preparation of cellulose derivatives containing amino groups and their use in cosmetic preparations for water treatment and papermaking

The invention relates to a process for the preparation of amino-containing cellulose derivatives by reacting alkali cellulose with amino group-containing reagents, starting from unsubstituted cellulose or cellulose derivatives in a reaction step, water-soluble or water-dispersible reaction products can be obtained.

Chitosan, 2-amino-2-deoxy-cellulose, is the only widely available cationic polysaccharide that can be used in a wide range of applications. It is used, inter alia, as acid-stable thickener in cosmetic preparations, as paper auxiliaries and as chelating agent and flocculant. The extraction of this natural polysaccharide, however, is a complex process, which is reflected in high prices of the products. The high price has hitherto hindered the widespread use of chitosan.

It is known that cellulose and its derivatives, primarily hydroxyethyl-containing cellulose ethers, for example, by the reaction with aminoalkyl chlorides of the general formula Cl- (CH ₂ ) _I i-NR ₂ can be converted into amino group-containing cellulose derivatives. In order to ensure the necessary thorough mixing of the batch, larger amounts of organic solvents are used, as described, for example, in US Pat. No. 2,623,042. In this case, only slight degrees of etherification are achieved in most cases and the amount of unwanted by-products is high.

DE-A 1 946 722 shows that this problem can be counteracted by using kneaders. In this case, predominantly water-soluble cellulose derivatives were kneaded in a solvent / water mixture and reacted with N- (2-chloroethyl) -N, N-diethylammonium chloride. Substitution degrees of 0.3 to 1.0 per anhydroglucose unit were achieved. A disadvantage here, however, is that in the technical implementation, the safety in dealing with combustible and volatile organic solvents (in the said patent primarily peroxide-forming dioxane) can be ensured only at increased cost guaranteed.

The workup and recovery of aqueous solvents and solvent mixtures requires high investment eg in distillation columns and requires disposal costs, eg for distillation residues. In addition, there is an increased risk of fire and explosion when using flammable solvents. The invention was therefore based on the object to provide an environmentally friendly, safe and kosten¬ favorable process for the preparation of amino group-containing cellulose derivatives.

The invention therefore provides a process for the preparation of amino-containing cellulose derivatives by reacting alkalized cellulose or alkalized cellulose derivatives with reagents of the general formula

X- (CH ₂ VNR ₁ R ₂

in which

X is a leaving group, preferably chlorine, bromine, iodine or a sulfonic acid radical R'SC> ₃ , where R 'is an aromatic or aliphatic radical having 1 to 24 C atoms, for example para-toluyl or methyl,

n must be at least 2

R 1 and R ₂ independently of one another are aliphatic or branched or cyclic, optionally heteroatom-substituted alkyl or aryl substituents having 1 to 24 C atoms or H or two radicals R 1 and R ₂ may form a ring together with the nitrogen,

characterized in that water is used as the reaction medium and the ratio of cellulose to water 1: 5 to 1: 40 moles per mole of anhydroglucose unit (AGU).

With the method according to the invention, the described disadvantages can be avoided. It has surprisingly been found that the use of organic solvents during the reaction can be dispensed with altogether. According to the invention, water is used as the reaction medium. The yields are surprisingly so good, despite the expected increased hydrolysis of the reagents, that cellulose-soluble or at least water-dispersible cellulose derivatives can be prepared from cellulose in one step. By dispensing with organic solvents, the work-up of the approaches is simplified considerably. Products are obtained, no residues of organic solvents used in the preparation, e.g. Dioxane, included ,.

It is possible to use cellulose of the most varied origin and characteristic profiles in the process according to the invention. Preferably, mechanically comminuted cellulose (beech, spruce, pine, eucalyptus, cotton) is used, for example, in chips, fiber or powder form. Cellulose derivatives can also be used. Cellulose derivatives are, for example, carboxymethyl, hydroxyethyl, hydroxypropyl, methyl and ethylcellulose and polysaccharides which are mixed with carboxymethyl, hydroxyethyl, hydroxypropyl, methyl and ethyl substituents and are substituted by carboxymethyl, hydroxyethyl, hydroxypropyl, methyl and ethyl. Particularly preferred are methyl cellulose, hydroxyethyl cellulose, methyl hydroxyethyl cellulose, ethyl cellulose, ethyl hydroxyethyl cellulose, hydroxypropyl cellulose, methyl hydroxypropyl cellulose and ethyl hydroxypropyl cellulose.

Preference is given to using a water-insoluble cellulose ether or a cellulose ether having a thermal flocculation point in water.

The total degree of substitution of the cellulose derivatives used for the reaction is preferably between 0.01 and 4, preferably between 0.1 and 3. The average degree of substitution of alkyl substituents (DS _A i _ky i) is between 0 and 2.5, preferably between 0 and 1, 7th The molar degree of substitution of hydroxyalkyl substituents (MS _Hy d _r o _x yai _k yi) is between 0 and 3.5 preferably between 0 and 2.5.

Suitable etherifying agents are compounds of the general formula

X- (CH ₂ VNR ₁ R ₂

in which

X is a leaving group, preferably chlorine, bromine, iodine or a sulfonic acid residue R'SC> ₃ , where R 'is an aromatic or aliphatic radical having 1 to 24 C atoms, for example para-toluyl or methyl,

n must be at least 2

the radicals Rj and R ₂ independently of one another are aliphatic or branched or cyclic, optionally substituted by hetero atoms, alkyl or aryl substituents having 1 to 24 C atoms or H. Two radicals R ₁ and R ₂ can form a ring together with the nitrogen.

X is particularly preferably chlorine.

Examples of etherification reagents to be used according to the invention are N-2-chloroethyldiisopropylamine, N-2-chloroethyldiethylamine, N-3-chloropropyldiethylamine, N-2-chloroethyldimethylamine and N-2-chloropropyldimethylamine. The radicals R 1 and R ₂ can form a cyclic radical together with the nitrogen. Examples of etherification reagents used according to the invention, in which two radicals R 1 and R ₂ together with the nitrogen N-2-chloroethylpyrrolidine, N-2-chloroethylpiperidine and N-2-chloroethylmorpholine. The etherifying reagents can be used in the form of the ammonium salts, preferably a hydrochloride. Both the solid and a solution of, for example, 65% or 50% by weight in water or other solvent may be used.

Preference is given to using N-2-chloroethyldiisopropylamine hydrochloride and N-2-chloroethyldiethylamine hydrochloride.

About 0.1-3 mol, preferably about 0.3-2 mol, more preferably about 1-2 mol of etherification reagent are used per mol of anhydroglucose, if cellulose is used as starting material.

When a cellulose derivative is used, 0.01 to 1.5 mol, preferably 0.1 to 1 mol, particularly preferably 0.1 to 0.8 mol of etherifying reagent per mol of anhydroglucose are sufficient.

The cellulose or the cellulose derivative is alkalized before the reaction with an aqueous solution of about 5-60 wt .-%, preferably 30 - 55 wt .-% of a base, preferably sodium hydroxide. The alkalization can be carried out directly in the reaction apparatus.

The cellulose or the cellulose derivative may, for example, before the reaction with a 5- 60 wt .-% aqueous solution of a base, preferably sodium hydroxide, and stirred for 10 - 120 min at room temperature. Then it is pressed in a defined way to a residual moisture. Then the thus activated cellulose, e.g. Alkalicellulose or a possibly pre-swollen by ammonium hydroxides cellulose, or an activated cellulose derivative in the reaction apparatus transferred. In addition to cellulose, water-insoluble cellulose derivatives are suitable for this form of activation.

Basically, e.g. It is also possible to use tetraalkylammonium hydroxides or sodium carbonate as the base, but preference is given to using alkali metal hydroxides, more preferably sodium hydroxide. Part of the base can be added as a solid.

It is preferable to use at least 0.1 equivalent of base per mole of etherifying reagent, more preferably at least 0.3 equivalent. At most 2 equivalents of base should be used per mole of etherifying reagent, preferably at most 1.5 mol and in a particularly preferred embodiment at most 1.2 mol.

The amount of base must be increased accordingly, if the etherifying reagent is used in the form of an ammonium salt, for example as the hydrochloride. Then at least one additional must equimolar amount, based on the ammonium salt, of base may be added to liberate the amine from the ammonium salt, for example from the hydrochloride.

The ratio of cellulose to water should be 1: 5 to 1:40 moles per mole of anhydroglucose unit and preferably between 1:10 and 1: 30 parts by weight.

The reaction mixture is treated at a temperature of 15-95 ^° C. and a time interval of 30 minutes-12 hours, the following parameters preferably being selected: 40-80 ^° C. and 1-4 hours.

To avoid and minimize molecular weight degradation, the reaction may be carried out in whole or in part under inert gas, e.g. Nitrogen or argon.

Suitable reaction apparatuses are known to the person skilled in the art and can be determined by design experiments. The apparatuses should allow thorough mixing and heating of the reaction product.

Particularly suitable reaction apparatuses are, for example, kneaders which are constructed from a double-trough-shaped kneading chamber, in which two kneading blades, which may be mutually scraping off, often rotate in Z- or sigma-shaped blades and cover almost the entire kneading space. Overall, high pressure, tensile and shear forces prevail in the kneaded by an alternate approach and removal of the blade surfaces to and from each other. Thus, a good mixing of highly viscous substances can be ensured. [Ramesh R. Hemrajani in: Kirk-Othmer Encyclopedia of Chemical Technology, "Mixing and Blending; 12. Mixing Dry Solids and Pastes"; John Wiley & Sons, 1995. DOL 10.1002 / 0471238961.1309240908051318.a01, Article Online Posting Date: December 4, 2000.]

The reaction mixture is taken up in water or a solvent / water mixture, optionally neutralized, washed with a suitable solvent, dried and optionally ground.

Suitable solvents for the washing of the product are those in which the product does not swell or only slightly swells. In the process according to the invention, amino-containing cellulose derivatives are preferably purified with water if neutralization is not required. As long as the filtrate has a pH> 7, preferably> 8 (measured in an aqueous solution of 1 wt .-%), swell or dissolve the products only slightly. The further washing can then be carried out with optionally aqueous organic solvents or solvent mixtures, for example acetone, if desired. The product can then continue in the form of the free amine processed or with an acid wholly or partially überfuhrt in the ammonium form and then processed further.

If desired, the reaction mixture can also after the reaction with an originating from the class of mineral acids or organic acids acid, preferably hydrochloric acid, are added. The further washing is then conveniently carried out with optionally aqueous organic solvents or solvent mixtures, e.g. aqueous acetone. If neutralized in this way, the pH of the product is preferably 7-4, more preferably about 6.5-5.

If necessary, the reaction product without special purification of a further reaction of the same type can be subjected to increase the nitrogen content and thus the DS. A mixed etherification with various amino group-containing etherifying reagents is possible according to the method described in the method according to the invention.

The erfϊndungsgemäße method is characterized by a simple procedure and gentle treatment of cellulose. It is universally applicable to a variety of celluloses. It is possible in a reaction step to obtain amino group-containing cellulose derivatives with degrees of substitution between 0.5 and 1.5 from unsubstituted celluloses. By dispensing with organic solvents, the use of explosion-proof equipment is not necessary in most cases.

Another object of the invention are amino group-containing cellulose derivatives

a) substituents of the type - (CHa) _n -NRiR ₂ bound to the cellulose or a side chain, eg hydroxyalkyl chain, wherein n is at least 2 and the radicals R ₁ and R _{2 are} independently aliphatic or branched or cyclic, optionally with heteroatoms substituted alkyl or aryl substituents having 1 to 24 carbon atoms or H or two radicals R ₁ and R ₂ together with the nitrogen can form a ring and

b) contain alkyl substituents of the type R ₃ , wherein preferably R ₃ = - (CH ₂ ) _m -CH ₃ with m = 0-3 and a DS _A i _k yi> 0.1 and

c) hydroxyalkyl substituents, preferably from the group hydroxyethyl, hydroxypropyl, hydroxybutyl, wherein the MS is _H ydroχya] _k yi> 0.1 and the

e) a total degree of substitution (sum of the individual degrees of substitution) of the substituents - (CH ₂ ) _n -NRiR ₂ , as well as R ₃ and hydroxyalkyl, determined from the nitrogen content [for substituents - (CH ₂ V NRiR ₂ ] or after Zeisel cleavage [DSAlkyl for substituents R ₃ or hydroxyalkyl], between 0.8 and 2.5.

The resulting amino group-containing cellulose derivatives can be used in many ways, for. B. in cosmetic preparations, especially hair care and shampoos. They can also be used in water treatment, in particular as flocculants or in papermaking, in particular as retention aids. These indicated uses are the subject of this invention.

example 1

243 g (1.5 mol) of humid, ground spruce sulfite pulp is alkalized in 5 L of 24% sodium hydroxide solution, pressed to an AGU: NaOH: water ratio of 1: 4: 29 and transferred to a horizontal kneader with 5 1-volume , After heating to 65 ⁰ C 600 g (3 mol) of NN-diisopropylaminoethyl chloride hydrochloride dissolved in 323 g of water (65% solution) are added with intensive kneading and the kneading continued for another 3 h. As a result, the ratio of reactants of AGU: NaOH: agent: water = 1: 4: 2: 40 is reached in the liquor. The resulting reaction product is filtered off with suction from the excess reaction liquid and washed with warm water until the pH of the effluent wash water remains constant. After drying, a white powder is obtained which has a nitrogen content of 5.80% (DS 1.14).

Example 2

243 g (1.5 mol) of pulp are poured over with 5 L of 25% sodium hydroxide solution and stirred for 1 h at room temperature. Thereafter, it is pressed until a ratio of anhydroglucose: NaOH: water of 1: 4: 20 is reached. 491 g (3 mol) of N, N-diisopropyl-aminoethyl chloride (free base) are added to the alkali metal cellulose formed over 5 minutes, and the temperature is raised to 65.degree. After a reaction time of 3 h, the formed, highly viscous mass is taken up in water and mechanically comminuted. Intensive washing removes salts and by-products. The nitrogen content determined by elemental analysis is 5.85% (DS 1.44).

Example 3

243 g (1.5 mol) of cellulose are alkalized in 5 L of 31% sodium hydroxide solution and then pressed the vorabgepreßte filter cake until a ratio of anhydroglucose: NaOH: water of 1: 4: 20 is reached. After heating to 55 ⁰ C, 600 g (3 mol) of N, N-diisopropylaminoethyl chloride hydrochloride was added in solid form and 3 h intensively kneaded at 40 min ^{is "1.} The reaction product is washed with water. After drying, the nitrogen content to 5.45% (DS 1.26).

Example 4

169 g (1 mol) of N, N-dimethylaminoethylcellulose (% N: 0.87 - DS: 0.10) is mixed with 595 ml of 17% sodium hydroxide solution, whereby the ratio AGU: NaOH: water to 1: 3: 32, 5 is set and then kneaded. After heating to 8O ⁰ C in the kneader is added to 327 g (2 mol) of NN-diisopropylaminoethyl chloride. After 4 hours of kneading the reaction mixture is treated with ethanol / water (1: 1 v / v) and neutralized with dilute hydrochloric acid. The polymer which has gone into solution is precipitated by addition of NaOH, washed with acetone and dried. The re-determined nitrogen content is now 6.03% (DS: 1.22).

Example 5

327 g (2 mol) of N, N-diisopropylaminoethyl chloride are added to 162 g (1 mol) of wood pulp and stored at room temperature for 12 h with exclusion of air. Then, 300 ml of 30% strength sodium hydroxide solution are added and the mixture is kneaded for 4 hours at 60 ⁰ C. The following ratio of reactants in the liquor is achieved: Anhydroglucose: NaOH: Agent: Water = 1: 3: 2: 15.5. After completion of the reaction is pressed and repeatedly washed with water until the wash water runs almost neutral. After drying, the white product is granulated. Elementary analysis shows a nitrogen content of 5.97% (DS 1.50).

Example 6

243 g (1.5 mol) of humid, ground pulp is mixed in a mixer with 50% sodium hydroxide solution (6 mol) and 45 min. mixed. There are 3 moles of N, N-diisopropylaminoethyl chloride

(6 5% solution) was added and the reaction continued for another 4 h. This will be in the

Reaction mixture a ratio of reactants of AGU: NaOH: agent: water = 1: 4: 2:

21.5 reached. The resulting reaction product is filtered off with suction from the excess reaction liquid and washed with warm water until the pH of the effluent washing water remains constant. After drying, a white powder is obtained which contains a

Nitrogen content of 5.80% (DS 1.14).

Claims

claims

1. A process for the preparation of amino-containing cellulose derivatives by reacting alkalized cellulose or alkalized cellulose derivatives with reagents of the general formula

X- (CH ₂ VNR ₁ R ₂

in which

X is a leaving group, preferably chlorine, bromine, iodine or a sulfonic acid residue R'SO ₃ , where R 'is an aromatic or aliphatic radical having 1 to 24 C atoms, for example para-toluyl or methyl,

n must be at least 2

R 1 and R ₂ independently of one another are aliphatic or branched or cyclic, optionally heteroatom-substituted alkyl or aryl substituents having 1 to 24 carbon atoms or H or two radicals R 1 and R ₂ may form a ring together with the nitrogen,

characterized in that water is used as the reaction medium and the

Ratio of cellulose to water 1: 5 to 1: 40 moles per mole of anhydroglucose unit (AGU).

2. The method according to claim 1, characterized in that 0.1 to 3 moles of etherifying reagent per AGU are used.

3. The method according to claim 1, characterized in that a cellulose ether is used as the cellulose derivative.

4. The method according to claim 3, characterized in that a cellulose ether with a total degree of substitution between 0.01 and 4, preferably between 0.1 and 3 is used as the cellulose derivative, wherein the average degree of substitution of alkyl substituents (ÜSA ^ _I ) between 0 and 2 , 5, more preferably between 0 and 1.7 and the molar degree of substitution of hydroxyalkyl substituents (MS _H yd _r o _x yai _k yi) is between 0 and 3.5, more preferably between 0 and 2.5.

5. The method according to claim 1, characterized in that 0.01 to 1.5 mol Veretherungs¬ reagent used per anhydroglucose unit.

6. The method according to claim 1, characterized in that the ratio of cellulose to water 1: 10 to 1: 30 moles per mole of anhydroglucose unit.

7. amino group-containing cellulose derivatives the

a) substituents of the type - (CHa) _n -NRiR ₂ contain, wherein n is at least 2 and the radicals Rj and R ₂ independently of one another aliphatic or branched or cyclic, optionally substituted with hetero atoms alkyl or aryl substituents with 1 - 24 C. Atom or H or two radicals Ri and R ₂ can form a ring together with the nitrogen and

b) contain alkyl substituents of the type R ₃ , wherein preferably R ₃ = - (CH ₂ ) _m -CH ₃ with m = 0-3 and a DS> 0.1 and

c) a total degree of substitution (sum of the individual degrees of substitution) of the substituents - (CH ₂ ) _n -NRiR ₂ and R ₃ , determined from the nitrogen content [for substituents - (CH ₂ ) _H -NRiR ₂ ] or after Zeisel cleavage [for substituents R ₃ ], between 0.8 and 2 per anhydroglucose unit.

8. Amino group-containing cellulose derivatives the

a) substituents of the type - (CH ₂ ) _n -NRiR ₂ bound to the cellulose or a side chain, eg hydroxyalkyl chain, wherein n is at least 2 and the radicals Ri and R _{2 are} independently aliphatic or branched or cyclic, optionally with heteroatoms substituted alkyl or aryl substituents having 1 to 24 carbon atoms or H or two radicals R ₁ and R ₂ together with the

Nitrogen can form a ring and

b) contain alkyl substituents of the type R ₃ , wherein preferably R ₃ = - (CH ₂ ) _H rCH ₃ with m = 0-3 and a DS _A i _k yi> 0.1 and

c) hydroxyalkyl substituents of type R ₄ , wherein preferably R ₄ = -CH ₂ -CH (C _p H _{2p +} i) O- {CH ₂ -CH (C _p H _{2p +} i) O} _q -C _r H _{2l + 1} with p = 0 or 1, q = 0-30, r = 0 or 1 and a MSHydroxyaikyi> 0.1 and the

d) a total degree of substitution (sum of the individual degrees of substitution) of the substituents - (CH ₂ ) _D -NR ₁ R ₂ , and R ₃ and R ₄ , determined from the nitrogen content [for substituents - (CH ₂ ) _n -NRiR ₂ ] or after Zeisel cleavage [for substituents R ₃ and R ₄ ], between 0.8 and 2.5 per anhydroglucose unit.

9. Use of obtainable according to claim 1 amino group-containing cellulose derivatives in cosmetic preparations.

10. Use according to claim 1 obtainable amino-containing cellulose derivatives in water treatment or in papermaking.