US20030040622A1 - Method for the preparation of modified cellulose ethers - Google Patents
Method for the preparation of modified cellulose ethers Download PDFInfo
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- US20030040622A1 US20030040622A1 US09/463,498 US46349800A US2003040622A1 US 20030040622 A1 US20030040622 A1 US 20030040622A1 US 46349800 A US46349800 A US 46349800A US 2003040622 A1 US2003040622 A1 US 2003040622A1
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- United States
- Prior art keywords
- cellulose
- cellulose ether
- akd
- alkyl
- weight
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 229920003086 cellulose ether Polymers 0.000 title claims abstract description 52
- 238000002360 preparation method Methods 0.000 title claims abstract description 9
- 238000000034 method Methods 0.000 title claims description 19
- 125000000217 alkyl group Chemical group 0.000 claims abstract description 19
- 239000000539 dimer Substances 0.000 claims abstract description 14
- 125000003342 alkenyl group Chemical group 0.000 claims abstract description 3
- 229920002134 Carboxymethyl cellulose Polymers 0.000 claims description 23
- 239000001768 carboxy methyl cellulose Substances 0.000 claims description 23
- 235000010948 carboxy methyl cellulose Nutrition 0.000 claims description 22
- 239000008112 carboxymethyl-cellulose Substances 0.000 claims description 22
- 229920002678 cellulose Polymers 0.000 claims description 11
- 239000001913 cellulose Substances 0.000 claims description 11
- 238000006467 substitution reaction Methods 0.000 claims description 10
- 238000006243 chemical reaction Methods 0.000 claims description 6
- WASQWSOJHCZDFK-UHFFFAOYSA-N diketene Chemical compound C=C1CC(=O)O1 WASQWSOJHCZDFK-UHFFFAOYSA-N 0.000 claims 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 15
- 239000003973 paint Substances 0.000 abstract description 8
- 239000011248 coating agent Substances 0.000 abstract description 6
- 238000000576 coating method Methods 0.000 abstract description 5
- 239000003599 detergent Substances 0.000 abstract description 4
- 238000005553 drilling Methods 0.000 abstract description 3
- 239000000203 mixture Substances 0.000 abstract description 3
- 239000003921 oil Substances 0.000 abstract description 3
- 239000002270 dispersing agent Substances 0.000 abstract description 2
- 239000000047 product Substances 0.000 description 16
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 9
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 7
- 230000004048 modification Effects 0.000 description 7
- 238000012986 modification Methods 0.000 description 7
- 229920000663 Hydroxyethyl cellulose Polymers 0.000 description 6
- 239000004354 Hydroxyethyl cellulose Substances 0.000 description 6
- 239000006185 dispersion Substances 0.000 description 6
- 235000019447 hydroxyethyl cellulose Nutrition 0.000 description 6
- 238000004519 manufacturing process Methods 0.000 description 6
- 239000000126 substance Substances 0.000 description 6
- 229920002153 Hydroxypropyl cellulose Polymers 0.000 description 5
- 0 [1*]C=C1OC(=O)C1[2*] Chemical compound [1*]C=C1OC(=O)C1[2*] 0.000 description 5
- 239000001863 hydroxypropyl cellulose Substances 0.000 description 5
- 235000010977 hydroxypropyl cellulose Nutrition 0.000 description 5
- 230000035484 reaction time Effects 0.000 description 5
- 239000002904 solvent Substances 0.000 description 5
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 4
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 4
- 229920001131 Pulp (paper) Polymers 0.000 description 4
- 239000007795 chemical reaction product Substances 0.000 description 4
- 150000001875 compounds Chemical class 0.000 description 4
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 4
- 239000007787 solid Substances 0.000 description 4
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 3
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- 239000008186 active pharmaceutical agent Substances 0.000 description 3
- 125000002057 carboxymethyl group Chemical group [H]OC(=O)C([H])([H])[*] 0.000 description 3
- 239000003153 chemical reaction reagent Substances 0.000 description 3
- 239000004035 construction material Substances 0.000 description 3
- 239000002537 cosmetic Substances 0.000 description 3
- 229910052731 fluorine Inorganic materials 0.000 description 3
- 239000011737 fluorine Substances 0.000 description 3
- -1 methyl hydroxypropyl Chemical group 0.000 description 3
- 239000000843 powder Substances 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 2
- 229920000742 Cotton Polymers 0.000 description 2
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 description 2
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 2
- 239000000853 adhesive Substances 0.000 description 2
- 230000001070 adhesive effect Effects 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 239000006227 byproduct Substances 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- FOCAUTSVDIKZOP-UHFFFAOYSA-N chloroacetic acid Chemical compound OC(=O)CCl FOCAUTSVDIKZOP-UHFFFAOYSA-N 0.000 description 2
- 150000002118 epoxides Chemical class 0.000 description 2
- 238000006266 etherification reaction Methods 0.000 description 2
- 235000013305 food Nutrition 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 150000004820 halides Chemical class 0.000 description 2
- 231100001261 hazardous Toxicity 0.000 description 2
- 230000036541 health Effects 0.000 description 2
- 230000002209 hydrophobic effect Effects 0.000 description 2
- 239000012299 nitrogen atmosphere Substances 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 230000009257 reactivity Effects 0.000 description 2
- 229940023144 sodium glycolate Drugs 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 125000001424 substituent group Chemical group 0.000 description 2
- JEJAMASKDTUEBZ-UHFFFAOYSA-N tris(1,1,3-tribromo-2,2-dimethylpropyl) phosphate Chemical compound BrCC(C)(C)C(Br)(Br)OP(=O)(OC(Br)(Br)C(C)(C)CBr)OC(Br)(Br)C(C)(C)CBr JEJAMASKDTUEBZ-UHFFFAOYSA-N 0.000 description 2
- JECYNCQXXKQDJN-UHFFFAOYSA-N 2-(2-methylhexan-2-yloxymethyl)oxirane Chemical compound CCCCC(C)(C)OCC1CO1 JECYNCQXXKQDJN-UHFFFAOYSA-N 0.000 description 1
- 241000157282 Aesculus Species 0.000 description 1
- CPELXLSAUQHCOX-UHFFFAOYSA-M Bromide Chemical compound [Br-] CPELXLSAUQHCOX-UHFFFAOYSA-M 0.000 description 1
- 239000004593 Epoxy Substances 0.000 description 1
- WQZGKKKJIJFFOK-GASJEMHNSA-N Glucose Natural products OC[C@H]1OC(O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-GASJEMHNSA-N 0.000 description 1
- 229920001479 Hydroxyethyl methyl cellulose Polymers 0.000 description 1
- 206010020751 Hypersensitivity Diseases 0.000 description 1
- 241000283986 Lepus Species 0.000 description 1
- DPXJVFZANSGRMM-UHFFFAOYSA-N acetic acid;2,3,4,5,6-pentahydroxyhexanal;sodium Chemical compound [Na].CC(O)=O.OCC(O)C(O)C(O)C(O)C=O DPXJVFZANSGRMM-UHFFFAOYSA-N 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 239000003905 agrochemical Substances 0.000 description 1
- 230000007815 allergy Effects 0.000 description 1
- 125000003118 aryl group Chemical group 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 125000004432 carbon atom Chemical group C* 0.000 description 1
- 125000004181 carboxyalkyl group Chemical group 0.000 description 1
- 229920003090 carboxymethyl hydroxyethyl cellulose Polymers 0.000 description 1
- 229910010293 ceramic material Inorganic materials 0.000 description 1
- 238000003776 cleavage reaction Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000001627 detrimental effect Effects 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000002360 explosive Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000004817 gas chromatography Methods 0.000 description 1
- 239000008103 glucose Substances 0.000 description 1
- 125000002791 glucosyl group Chemical group C1([C@H](O)[C@@H](O)[C@H](O)[C@H](O1)CO)* 0.000 description 1
- 150000004676 glycans Chemical class 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 150000003944 halohydrins Chemical class 0.000 description 1
- 125000005842 heteroatom Chemical group 0.000 description 1
- 235000010181 horse chestnut Nutrition 0.000 description 1
- 125000001165 hydrophobic group Chemical group 0.000 description 1
- 125000002768 hydroxyalkyl group Chemical group 0.000 description 1
- 239000000976 ink Substances 0.000 description 1
- NONOKGVFTBWRLD-UHFFFAOYSA-N isocyanatosulfanylimino(oxo)methane Chemical compound O=C=NSN=C=O NONOKGVFTBWRLD-UHFFFAOYSA-N 0.000 description 1
- 239000011499 joint compound Substances 0.000 description 1
- CCGKOQOJPYTBIH-UHFFFAOYSA-N ketene group Chemical group C=C=O CCGKOQOJPYTBIH-UHFFFAOYSA-N 0.000 description 1
- 239000004816 latex Substances 0.000 description 1
- 229920000126 latex Polymers 0.000 description 1
- 238000009992 mercerising Methods 0.000 description 1
- 229920000609 methyl cellulose Polymers 0.000 description 1
- 239000001923 methylcellulose Substances 0.000 description 1
- 235000010981 methylcellulose Nutrition 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 238000006386 neutralization reaction Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 229920001282 polysaccharide Polymers 0.000 description 1
- 239000005017 polysaccharide Substances 0.000 description 1
- 239000012429 reaction media Substances 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 230000007017 scission Effects 0.000 description 1
- 235000019812 sodium carboxymethyl cellulose Nutrition 0.000 description 1
- 229920001027 sodium carboxymethylcellulose Polymers 0.000 description 1
- 239000011780 sodium chloride Substances 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 239000004753 textile Substances 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08B—POLYSACCHARIDES; DERIVATIVES THEREOF
- C08B13/00—Preparation of cellulose ether-esters
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08B—POLYSACCHARIDES; DERIVATIVES THEREOF
- C08B11/00—Preparation of cellulose ethers
- C08B11/20—Post-etherification treatments of chemical or physical type, e.g. mixed etherification in two steps, including purification
-
- C—CHEMISTRY; METALLURGY
- C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
- C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
- C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
- C11D3/16—Organic compounds
- C11D3/20—Organic compounds containing oxygen
- C11D3/22—Carbohydrates or derivatives thereof
- C11D3/222—Natural or synthetic polysaccharides, e.g. cellulose, starch, gum, alginic acid or cyclodextrin
- C11D3/225—Natural or synthetic polysaccharides, e.g. cellulose, starch, gum, alginic acid or cyclodextrin etherified, e.g. CMC
-
- C—CHEMISTRY; METALLURGY
- C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
- C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
- C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
- C11D3/16—Organic compounds
- C11D3/20—Organic compounds containing oxygen
- C11D3/22—Carbohydrates or derivatives thereof
- C11D3/222—Natural or synthetic polysaccharides, e.g. cellulose, starch, gum, alginic acid or cyclodextrin
- C11D3/226—Natural or synthetic polysaccharides, e.g. cellulose, starch, gum, alginic acid or cyclodextrin esterified
Definitions
- the invention relates to the preparation of hydrophobically modified cellulose ethers.
- Cellulose ethers such as carboxymethyl cellulose
- Objects of use include, for example, foods, medicines, cosmetic preparations, detergents, agricultural chemicals, textiles, printing inks, paper coating agents, construction materials, adhesives, paints, ceramic materials, and additives of polymerisation.
- Cellulose ethers can be modified by attaching different substituents to hydroxyl groups in cellulose. In this way, the solubility or the hydrophobicity of cellulose ether in particular can be affected.
- U.S. Pat. No. 4,228,277 describes the modification of non-ionic cellulose ethers, such as methyl cellulose, methyl hydroxypropyl cellulose, hydroxypropyl cellulose, and particularly hydroxyethyl cellulose, by using epoxyalkanes having a length of the alkyl group of 10 to 24 carbons.
- one advantage of the modification is that even small amounts of hydrophobically modified cellulose ether make the viscosity of an aqueous solution increase so that the dosage of the cellulose ether can be decreased.
- the cellulose ether thus modified can be used in paints.
- the modification is carried out by using a cellulose ether as a starting material, and the reaction times are long, 2 to 5 hours. However, it is uncomfortable to use epoxy compounds because they are detrimental to health.
- carboxymethyl hydroxyethyl cellulose is modified by an alkyl group having 8 to 25 carbons in an amount of 0.1 to 4% by weight.
- the alkyl reagent can be halide, halohydride, or epoxide, all of which are hazardous to environment and health. Hydroxyethylation, hydrophobic modification and carboxymethylation are carried out in sequence, therefore the reaction time is long, more than 4 hours.
- U.S. Pat. No. 5,302,196 describes cellulose ethers which are modified by a fluorine-containing alkyl group having 3 to 24 carbon atoms, the fluorine content being 0.05 to 5% by weight.
- the cellulose ether is especially hydroxyethyl cellulose, hydroxyethyl carboxymethyl cellulose or methyl hydroxyethyl cellulose.
- the fluorine-containing alkyl reagent is preferably epoxide, bromide or perfluoroolefin. This product is also developed for paints. The reaction is long, the modification requires a reaction time of 6 hours.
- cellulose ether especially hydroxyethyl cellulose
- an aromatic alkyl group having at least 10 carbons, the content being 0.001 to 0.1 moles per one mole of a glucose repeat unit of the cellulose ether.
- the alkyl reagent can be, for example, halide, oxirane, acid, (thio)isocyanate or halohydrin.
- the product can be used in latex paints. This manufacturing process also has a long reaction time, 6 or up to 12 hours.
- This invention introduces a new type of hydrophobically modified cellulose ether in which the modifying agent is alkylketene dimer.
- the cellulose ether is preferably carboxymethyl cellulose or sodium carboxymethyl cellulose (CMC, NaCMC).
- Cellulose ether modified with alkylketene dimer is easy to manufacture. The process is safe, simple, and quick. The modification can also improve the dispersability of cellulose ether in water.
- the product is suitable to be used in any water-based application.
- the hydrophobic group renders the substance properties that are advantageous to, for example, detergents, paper coating mixtures, paints, dispersing agents, and oil drilling muds.
- alkylketene dimer is used to modify the cellulose ether.
- the general formula of AKD is
- R 1 and R 2 are alkyl or alkenyl chains having 5 to 22, preferably 13 to 20 carbons.
- R 1 or R 2 can also be substituted or they can contain heteroatoms in a chain.
- R 1 and R 2 can in particular have a straight chain and contain 14 to 18 carbons.
- AKD may react with the hydroxyl group of cellulose or cellulose ether, forming the following formula:
- Elevated reaction temperatures are preferable, such as 30-120° C., preferably 50-90° C., and most preferably 60-85° C., so that at elevated temperatures AKD is melted first.
- High temperature and alkaline pH improve the reactivity of AKD with cellulose lose ether.
- AKD can react with substituents, for example carboxymethyl groups in cellulose ether.
- AKD can also react with other compounds which contain an OH group. These include water, alcohol, and sodium glycolate which are generated in the preparation of CMC. The thus generated compounds also have an effect on the hydrophobicity of the product.
- the reacted AKD concentration in the cellulose ether can be analysed by using gas chromatography.
- the unreacted AKD or AKD reacted with other OH containing compounds are extracted with a suitable solvent.
- the sample is hydrolysed causing the cleavage of alkyl ketene group.
- the reacted AKD is extracted with a suitable solvent and analysed with gas chromatograph.
- the AKD can be in a solid state or dispersed in water or other solvents.
- the content of AKD in the cellulose ether can be 0.001-10% by weight.
- the content is preferably 0.01-2% by weight.
- the molecular weight (Mw) of the cellulose ether can be 10 000 -1 000 000, preferably 20 000 -700 000.
- the cellulose ether can be, for example, alkyl, hydroxyalkyl or carboxyalkyl substituted or a mixed ether of these.
- cellulose ether that is modified by AKD can be used in any water-based application. It can be used, for example, in paper or board coating mixtures, in the wet end in paper or board manufacturing, paints, construction materials, adhesives, oil drilling mud, detergents, cosmetic products, and as a dispersion agent.
- the cellulose ether is preferably carboxymethyl cellulose (CMC).
- CMC carboxymethyl cellulose
- Its degree of substitution i.e., the average number of substituted hydroxyl groups in a glucose ring
- DS degree of substitution
- Its molecular weight is preferably 40 000 -500 000. It can be applied to all the above-mentioned objects.
- the cellulose ether can also be, e.g., hydroxyethyl cellulose (HEC). Its molecular weight can be, for example, 90 000 -1 300 000 and the molar substitution (MS) 1.5-4. HEC can be used in coating, construction materials, and cosmetic preparations in particular.
- HEC hydroxyethyl cellulose
- the cellulose ether can also be, e.g., hydroxypropyl cellulose (HPC). Its molecular weight can be, for example, 80 000 -1 150 000 and the molar substitution (MS) 1.5-4. HPC can be used in foods, medical preparations, and coating in particular.
- HPC hydroxypropyl cellulose
- cellulose ethers are prepared by mixing wood-based or cotton wool-based raw material with a reaction medium, such as alcohol or acetone, and by mercerising it with an alkalic substance, such as sodium hydroxide, to activate the cellulose.
- a reaction medium such as alcohol or acetone
- an alkalic substance such as sodium hydroxide
- An etherifying chemical is added and it is allowed to react.
- the complete product is neutralised.
- the viscosity can be reduced if needed.
- By-products, such as salts generated in the reaction are washed out with alcohol, for example, when purified cellulose ether is manufactured. but they can also be left in the product or only remove partly (technical or crude cellulose ether).
- the solvent used is separated and the product is dried.
- the particle size and the bulk density can be adjusted by grinding the product into powder or by granulating it.
- the product can also be screened.
- Cellulose ether can be modified with AKD by various methods.
- AKD can be added to the cellulose ether at any stage of the production, for example, in mercerisation, etherification, or drying.
- AKD can be added in a solid form or as a dispersion. High temperature and alkaline pH improve the reactivity of AKD with cellulose ether.
- AKD can also be added to the cellulose ether as such.
- the cellulose ether can be coated, for example, with solid AKD or an AKD dispersion. In that case, a suitable amount of AKD is sprayed onto the surface of the cellulose ether or mixed with it. The product is treated with high temperature to initiate the reaction.
- AKD is a safe chemical. It is neither combustible nor explosive; therefore, it neither causes a danger in a process nor is it dangerous to the environment. AKD is not hazardous or irritating and it does not cause allergies; therefore, it does not present any danger to the process personnel or the end-user.
- alkylketene dimer the length of the alkyl group being 16 to 18 carbons (Raisio Chemicals).
- CMC Metal Organic Chemicals
- alkylketene dimer dispersion having an AKD content of 10% by weight, diluted with 50 g of water, was sprayed on CMC, agitating the powder at the same time.
- the product was dried at 80° C. to a moisture content of less than 8%.
- the AKD content of the end product was 0.1% by weight.
- Hydrophobically modified CMC having an average molecular weight of 400 000 and a degree of substitution of 0.86, and an AKD content of 10.0% by weight, was prepared according to the procedure described in example 7.
- Ethanol was recovered and the product was dried at 80° C. to a moisture content of less than 8%.
- the AKD content of the end product was 0.3% by weight, the average molecular weight 150 000, and the DS of the carboxymethyl group 0.57.
- the sample contained 0.02% by weight of AKD reacted with cellulose.
- Samples 10-15 were prepared according to the procedure described in example 9.
- the product was neutralised after etherification with hydrochloric acid.
- AKD was added after neutralisation and allowed to react 5 minutes at 70° C.
- TABLE 2 Molecular Degree of AKD content weight substitution in CMC, Example of CMC of CMC % by weight 10 180 000 0.46 0.6 11 120 000 0.48 0.6 12 140 000 0.52 0.06 13 150 000 0.55 1.1 14 140 000 0.56 2.7 15 270 000 0.52 0.06
- CMC was neutralised with hydrochloric acid.
- Samples 17-19 were prepared according to the procedure described in example 16. In example 19 AKD was added during mercerisation. TABLE 3 AKD Molecular Degree of content in weight substitution CMC, % Example Raw material of CMC of CMC by weight 17 wood pulp 60 000 0.77 0.07 (Metsa-Botnia) 18 wood pulp 240 000 0.89 0.07 (Borregaard) 19 cotton linter 380 000 0.80 0.7 (Buckeye, Temming)
Abstract
The invention relates to the preparation of a cellulose ether that is hydrophobically modified with an alkyl or alkenylketene dimer the general formula of which is
in which R1 and R2 are alkyl or alkenyl chain, such as one having 5 to 22, preferably 13 to 20, most preferably 14 to 18 carbons. The product can be used in water-based products to control the rheological properties, for example. Objects of use include, for example, detergents, paper coating mixtures, paints, dispersing agents, and oil drilling muds.
Description
- The invention relates to the preparation of hydrophobically modified cellulose ethers.
- Cellulose ethers, such as carboxymethyl cellulose, are employed in a wide variety of applications to treat the rheological properties of aqueous solutions in particular. Objects of use include, for example, foods, medicines, cosmetic preparations, detergents, agricultural chemicals, textiles, printing inks, paper coating agents, construction materials, adhesives, paints, ceramic materials, and additives of polymerisation.
- Cellulose ethers can be modified by attaching different substituents to hydroxyl groups in cellulose. In this way, the solubility or the hydrophobicity of cellulose ether in particular can be affected.
- There is a lot of literature concerning the hydrophobic modification of polysaccharides.
- U.S. Pat. No. 4,228,277 describes the modification of non-ionic cellulose ethers, such as methyl cellulose, methyl hydroxypropyl cellulose, hydroxypropyl cellulose, and particularly hydroxyethyl cellulose, by using epoxyalkanes having a length of the alkyl group of 10 to 24 carbons. According to the patent, one advantage of the modification is that even small amounts of hydrophobically modified cellulose ether make the viscosity of an aqueous solution increase so that the dosage of the cellulose ether can be decreased. The cellulose ether thus modified can be used in paints. The modification is carried out by using a cellulose ether as a starting material, and the reaction times are long, 2 to 5 hours. However, it is uncomfortable to use epoxy compounds because they are detrimental to health.
- In FI Patent No. 95138, carboxymethyl hydroxyethyl cellulose is modified by an alkyl group having 8 to 25 carbons in an amount of 0.1 to 4% by weight. This product is also applied to paints. The alkyl reagent can be halide, halohydride, or epoxide, all of which are hazardous to environment and health. Hydroxyethylation, hydrophobic modification and carboxymethylation are carried out in sequence, therefore the reaction time is long, more than 4 hours.
- U.S. Pat. No. 5,302,196 describes cellulose ethers which are modified by a fluorine-containing alkyl group having 3 to 24 carbon atoms, the fluorine content being 0.05 to 5% by weight. The cellulose ether is especially hydroxyethyl cellulose, hydroxyethyl carboxymethyl cellulose or methyl hydroxyethyl cellulose. The fluorine-containing alkyl reagent is preferably epoxide, bromide or perfluoroolefin. This product is also developed for paints. The reaction is long, the modification requires a reaction time of 6 hours.
- In EP Patent Application No. 384167, cellulose ether, especially hydroxyethyl cellulose, is modified with an aromatic alkyl group having at least 10 carbons, the content being 0.001 to 0.1 moles per one mole of a glucose repeat unit of the cellulose ether. The alkyl reagent can be, for example, halide, oxirane, acid, (thio)isocyanate or halohydrin. The product can be used in latex paints. This manufacturing process also has a long reaction time, 6 or up to 12 hours.
- According to the independent claim 1, a method for the preparation of hydrophobically modified cellulose ethers hase been invented. The other claims disclose some preferred embodiments of the invention.
- This invention introduces a new type of hydrophobically modified cellulose ether in which the modifying agent is alkylketene dimer. The cellulose ether is preferably carboxymethyl cellulose or sodium carboxymethyl cellulose (CMC, NaCMC).
- Cellulose ether modified with alkylketene dimer is easy to manufacture. The process is safe, simple, and quick. The modification can also improve the dispersability of cellulose ether in water.
- The product is suitable to be used in any water-based application. The hydrophobic group renders the substance properties that are advantageous to, for example, detergents, paper coating mixtures, paints, dispersing agents, and oil drilling muds.
-
- in which R1 and R2 are alkyl or alkenyl chains having 5 to 22, preferably 13 to 20 carbons. R1 or R2 can also be substituted or they can contain heteroatoms in a chain. R1 and R2 can in particular have a straight chain and contain 14 to 18 carbons.
-
- Elevated reaction temperatures are preferable, such as 30-120° C., preferably 50-90° C., and most preferably 60-85° C., so that at elevated temperatures AKD is melted first. High temperature and alkaline pH improve the reactivity of AKD with cellulose lose ether. AKD can react with substituents, for example carboxymethyl groups in cellulose ether. AKD can also react with other compounds which contain an OH group. These include water, alcohol, and sodium glycolate which are generated in the preparation of CMC. The thus generated compounds also have an effect on the hydrophobicity of the product.
- The reacted AKD concentration in the cellulose ether can be analysed by using gas chromatography. The unreacted AKD or AKD reacted with other OH containing compounds are extracted with a suitable solvent. The sample is hydrolysed causing the cleavage of alkyl ketene group. The reacted AKD is extracted with a suitable solvent and analysed with gas chromatograph.
- The AKD can be in a solid state or dispersed in water or other solvents.
- The content of AKD in the cellulose ether can be 0.001-10% by weight. The content is preferably 0.01-2% by weight.
- The molecular weight (Mw) of the cellulose ether can be 10 000 -1 000 000, preferably 20 000 -700 000. The cellulose ether can be, for example, alkyl, hydroxyalkyl or carboxyalkyl substituted or a mixed ether of these.
- According to the invention, cellulose ether that is modified by AKD can be used in any water-based application. It can be used, for example, in paper or board coating mixtures, in the wet end in paper or board manufacturing, paints, construction materials, adhesives, oil drilling mud, detergents, cosmetic products, and as a dispersion agent.
- The cellulose ether is preferably carboxymethyl cellulose (CMC). Its degree of substitution (DS, i.e., the average number of substituted hydroxyl groups in a glucose ring) can be, for example, 0.2-2.0, preferably 0.4-1.5, most preferably 0.4-1.2. Its molecular weight is preferably 40 000 -500 000. It can be applied to all the above-mentioned objects.
- The cellulose ether can also be, e.g., hydroxyethyl cellulose (HEC). Its molecular weight can be, for example, 90 000 -1 300 000 and the molar substitution (MS) 1.5-4. HEC can be used in coating, construction materials, and cosmetic preparations in particular.
- The cellulose ether can also be, e.g., hydroxypropyl cellulose (HPC). Its molecular weight can be, for example, 80 000 -1 150 000 and the molar substitution (MS) 1.5-4. HPC can be used in foods, medical preparations, and coating in particular.
- There is a lot of literature about the manufacture of cellulose ethers. Generally, cellulose ethers are prepared by mixing wood-based or cotton wool-based raw material with a reaction medium, such as alcohol or acetone, and by mercerising it with an alkalic substance, such as sodium hydroxide, to activate the cellulose. An etherifying chemical is added and it is allowed to react. The complete product is neutralised. The viscosity can be reduced if needed. By-products, such as salts generated in the reaction, are washed out with alcohol, for example, when purified cellulose ether is manufactured. but they can also be left in the product or only remove partly (technical or crude cellulose ether). The solvent used is separated and the product is dried. The particle size and the bulk density can be adjusted by grinding the product into powder or by granulating it. The product can also be screened.
- Cellulose ether can be modified with AKD by various methods. AKD can be added to the cellulose ether at any stage of the production, for example, in mercerisation, etherification, or drying. AKD can be added in a solid form or as a dispersion. High temperature and alkaline pH improve the reactivity of AKD with cellulose ether.
- AKD can also be added to the cellulose ether as such. The cellulose ether can be coated, for example, with solid AKD or an AKD dispersion. In that case, a suitable amount of AKD is sprayed onto the surface of the cellulose ether or mixed with it. The product is treated with high temperature to initiate the reaction.
- The manufacture of the hydrophobically modified cellulose ether according to the invention is simple and quick. Neither complex solvents nor long reaction times are needed. In addition, AKD is a safe chemical. It is neither combustible nor explosive; therefore, it neither causes a danger in a process nor is it dangerous to the environment. AKD is not hazardous or irritating and it does not cause allergies; therefore, it does not present any danger to the process personnel or the end-user.
- All examples employed alkylketene dimer, the length of the alkyl group being 16 to 18 carbons (Raisio Chemicals).
- 100 g of CMC (Metsa Speciality Chemicals) having an average molecular weight of 180 000 and a degree of substitution of 0.65 was put into a steel container. 1 g of alkylketene dimer dispersion having an AKD content of 10% by weight, diluted with 50 g of water, was sprayed on CMC, agitating the powder at the same time. The product was dried at 80° C. to a moisture content of less than 8%. The AKD content of the end product was 0.1% by weight.
- By using the procedure described above, the following hydrophobically modified CMC samples (examples 2-6) were prepared:
TABLE 1 Molecular Degree of AKD content weight substitution in CMC, Example of CMC of CMC % by weight 2 60 000 0.72 0.05 3 300 000 0.80 0.05 4 220 000 0.87 0.1 5 305 000 1.15 1.0 6 80 000 0.75 0.01 - 100 g of CMC having an average molecular weight of 40 000 and a degree of substitution of 0.79 was put into a steel cylinder. 5 g of solid alkylketene dimer was added. The powder was agitated in an oven at 60° C. for 120 minutes and at 105° C. for 15 min. The AKD content of the end product was 5.0% by weight.
- Hydrophobically modified CMC having an average molecular weight of 400 000 and a degree of substitution of 0.86, and an AKD content of 10.0% by weight, was prepared according to the procedure described in example 7.
- 47 g of wood pulp (Metsä-Botnia), 175 g of ethanol, and 20 g of water were mixed together in a closed glass flask which was provided with a mixer and a nitrogen atmosphere as an option. The flask was placed in a water bath. 18 g of sodium hydroxide, diluted with 18 g of water, was added and the cellulose was mercerised for 30 minutes at 20° C. 22 g of monochloracetic acid, diluted with 6 g of water, and 1.25 g of alkylketene dimer dispersion having an AKD content of 20% by weight were added and the temperature was raised in 55 minutes to 65° C. The cellulose was etherified for 60 minutes at 65° C. Ethanol was recovered and the product was dried at 80° C. to a moisture content of less than 8%. The AKD content of the end product was 0.3% by weight, the average molecular weight 150 000, and the DS of the carboxymethyl group 0.57. The sample contained 0.02% by weight of AKD reacted with cellulose.
- Samples 10-15 were prepared according to the procedure described in example 9. In example 10 and 15 the product was neutralised after etherification with hydrochloric acid. In example 10 AKD was added after neutralisation and allowed to react 5 minutes at 70° C.
TABLE 2 Molecular Degree of AKD content weight substitution in CMC, Example of CMC of CMC % by weight 10 180 000 0.46 0.6 11 120 000 0.48 0.6 12 140 000 0.52 0.06 13 150 000 0.55 1.1 14 140 000 0.56 2.7 15 270 000 0.52 0.06 - 100 g of wood pulp (Metsä-Botnia), 1270 g of isopropanol, and 162 g of water were mixed together in a closed glass flask which was provided with a mixer and a nitrogen atmosphere. The flask was placed in a water bath. 40 g of sodium hydroxide, diluted with 40 g of water, was added and the cellulose was mercerised for 90 minutes at 20° C. 44 g of monochloracetic acid, diluted with 11 g of water, and 1 g of alkylketene dimer dispersion having an AKD content of 10% by weight were added, and the temperature was raised in 45 minutes to 70° C. The cellulose was etherified for 90 minutes at 70° C. CMC was neutralised with hydrochloric acid. The by-products of the reaction, sodium chloride and sodium glycolate, were washed out with 75% methanol, and the product was dried at 80° C. to a moisture content of less than 8%. The AKD content of the end product was 0.08%, the average molecular weight 270 000, and the DS of the carboxymethyl group 0.59.
- Samples 17-19 were prepared according to the procedure described in example 16. In example 19 AKD was added during mercerisation.
TABLE 3 AKD Molecular Degree of content in weight substitution CMC, % Example Raw material of CMC of CMC by weight 17 wood pulp 60 000 0.77 0.07 (Metsa-Botnia) 18 wood pulp 240 000 0.89 0.07 (Borregaard) 19 cotton linter 380 000 0.80 0.7 (Buckeye, Temming)
Claims (9)
1. A method for the preparation of a hydrophobically modified cellulose ether, characterised in that
a cellulose ether is allowed to react with alkyl or alkenylketene dimer or
a cellulose or its derivative is allowed to react with alkyl or alkenylketene dimer, whereafter the product is converted into a cellulose ether.
4. A method according to any of claims 1-3, wherein the content of ketene dimer in the cellulose ether is 0.001-10% by weight, preferably 0.01-2% by weight.
5. A method according to any of claims 1-4, wherein the molecular weight of the cellulose ether is 10 000 -1 000 000, preferably 20 000 -700 000, most preferably 40 000 -500 000.
6. A method according to any of claims 1-5 wherein the cellulose ether is carboxymethyl cellulose.
7. A method according to claim 6 , wherein the degree of substitution of the carboxymethyl cellulose is 0.2-2, preferably 0.4-1.5, and most preferably 0.4-1.2.
8. A method according to any of claims 1-7, wherein the reaction is carried out at an elevated temperature, such as 30-120° C., preferably 50-90° C., and most preferably 60-85° C.
9. A method for hydrophobically modifying a cellulose ether, characterised in that
a cellulose ether is allowed to react with the alkyl or alkenylketene dimer or
a cellulose or its derivative is allowed to react with the alkyl or alkenylketene dimer, whereafter the product is converted into a cellulose ether.
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FI981149A FI107385B (en) | 1998-05-25 | 1998-05-25 | Preparation of modified cellulose ethers |
FI981149 | 1998-05-25 |
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US09/463,498 Abandoned US20030040622A1 (en) | 1998-05-25 | 1999-04-08 | Method for the preparation of modified cellulose ethers |
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US (2) | US6600033B1 (en) |
EP (2) | EP2078733A1 (en) |
JP (1) | JP4468579B2 (en) |
KR (1) | KR100362421B1 (en) |
CN (1) | CN1191278C (en) |
AR (1) | AR016721A1 (en) |
AT (1) | ATE444312T1 (en) |
AU (1) | AU3422399A (en) |
BR (1) | BR9906504B1 (en) |
CA (1) | CA2297904C (en) |
CO (1) | CO5050321A1 (en) |
DE (1) | DE69941472D1 (en) |
ES (1) | ES2333186T3 (en) |
FI (1) | FI107385B (en) |
HK (1) | HK1027823A1 (en) |
HU (1) | HUP0100160A3 (en) |
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TR (1) | TR200000242T1 (en) |
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Cited By (2)
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US20070105985A1 (en) * | 2005-11-04 | 2007-05-10 | Gillette Paul C | Ether derivatives of raw cotton linters for water-borne coatings |
CN108048236A (en) * | 2017-12-01 | 2018-05-18 | 纳爱斯浙江科技有限公司 | A kind of liquid detergent containing carboxymethyl cellulose and preparation method thereof |
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FI19992519A (en) * | 1999-11-25 | 2001-05-26 | Neste Chemicals Oy | A method for acetoacetylation of nucleophilic compounds |
US6528643B1 (en) | 2000-05-05 | 2003-03-04 | Hercules Incorporated | Esterified polysaccharide products and B-lactone ring opened ketene dimer products containing the compositions, and process of making the same |
US6677427B1 (en) | 2000-06-13 | 2004-01-13 | Hercules Incorporated | Enzyme-catalyzed polyamides and compositions and processes of preparing and using the same |
US6528644B1 (en) | 2001-09-26 | 2003-03-04 | Hercules Incorporated | Acetoacetylated saccharides and process of making the same |
GB0227242D0 (en) * | 2002-11-21 | 2002-12-31 | Unilever Plc | Improvements relating to fabric laundering |
JP5007985B2 (en) * | 2004-06-25 | 2012-08-22 | 国立大学法人 東京大学 | Polymer brush compound and preparation method thereof |
GB0419689D0 (en) | 2004-09-04 | 2004-10-06 | Unilever Plc | Improvements relating to fabric laundering |
EP2085070A1 (en) * | 2008-01-11 | 2009-08-05 | Procter & Gamble International Operations SA. | Cleaning and/or treatment compositions |
EP2302025B1 (en) | 2009-09-08 | 2016-04-13 | The Procter & Gamble Company | A laundry detergent composition comprising a highly water-soluble carboxmethyl cellulose particle |
CN102443067B (en) * | 2011-10-28 | 2013-03-20 | 东北林业大学 | Method for preparing carboxide modified nanometre cellulose |
CN104629508B (en) * | 2015-03-11 | 2018-03-06 | 马清浩 | Wall emulsion paint inside and outside a kind of water-fast scrubbing resistance |
DE17784205T1 (en) | 2016-09-28 | 2019-11-28 | Cp Kelco Oy | DETERGENT COMPOSITIONS WITH POLYSACCHARIDES WITH EXTREMELY LOW MOLECULAR WEIGHT |
WO2019111937A1 (en) * | 2017-12-06 | 2019-06-13 | 花王株式会社 | Washing agent composition for textile product |
US11872711B2 (en) | 2019-05-10 | 2024-01-16 | The Gillette Company Llc | Lubricating member for razor cartridges |
CN110563855A (en) * | 2019-10-12 | 2019-12-13 | 山东省食品发酵工业研究设计院 | Synthesis method of self-assembled nanoparticle material-octadecanoyl octadecanoic acid pullulan polysaccharide ester |
CN111995691A (en) * | 2020-08-21 | 2020-11-27 | 南京林业大学 | Cellulose ether derivative, preparation method and application |
EP4269548A1 (en) | 2022-04-27 | 2023-11-01 | Dalli-Werke GmbH & Co. KG | Detergent composition with antiscalants |
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US2627477A (en) * | 1949-10-06 | 1953-02-03 | Hercules Powder Co Ltd | Higher alkyl ketene dimer emulsion |
SE361908B (en) | 1972-07-14 | 1973-11-19 | Kema Nord Ab | |
JPS50120836A (en) * | 1974-03-08 | 1975-09-22 | ||
US4228277A (en) | 1979-02-12 | 1980-10-14 | Hercules Incorporated | Modified nonionic cellulose ethers |
GB8621680D0 (en) | 1986-09-09 | 1986-10-15 | Du Pont | Filler compositions |
US4826970A (en) | 1987-09-17 | 1989-05-02 | Hercules Incorporated | Carboxymethyl hydrophobically modified hydroxyethylcellulose |
CA2008935C (en) | 1989-01-31 | 1999-02-16 | George L. Ii Brode | Polysaccharides with alkyl-aryl aromatic hydrophobes and latex compositions containing same |
DE4028746A1 (en) | 1990-09-11 | 1992-03-12 | Hoechst Ag | MODIFIED CELLULOSE ETHERS AND THEIR USE IN DISPERSION COLORS |
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1998
- 1998-05-25 FI FI981149A patent/FI107385B/en not_active IP Right Cessation
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- 1999-04-08 TR TR2000/00242T patent/TR200000242T1/en unknown
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- 1999-04-08 AU AU34223/99A patent/AU3422399A/en not_active Abandoned
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- 1999-04-08 EP EP99914585A patent/EP0998498B9/en not_active Expired - Lifetime
- 1999-04-08 US US09/463,498 patent/US20030040622A1/en not_active Abandoned
- 1999-04-08 CN CNB998008354A patent/CN1191278C/en not_active Expired - Fee Related
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Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20070105985A1 (en) * | 2005-11-04 | 2007-05-10 | Gillette Paul C | Ether derivatives of raw cotton linters for water-borne coatings |
US7932309B2 (en) * | 2005-11-04 | 2011-04-26 | Hercules Incorporated | Ether derivatives of raw cotton linters for water-borne coatings |
CN108048236A (en) * | 2017-12-01 | 2018-05-18 | 纳爱斯浙江科技有限公司 | A kind of liquid detergent containing carboxymethyl cellulose and preparation method thereof |
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