MECHANICAL TREATMENT OF POLYSACCHARIDE WITH HYDROPHOBIC ALCOHOL

Abstract

The present invention relates to a process for the preparation of an alkyl polyglycoside comprising the step of mechanically treating a polysaccharide in the presence of an acid and a hydrophobic alcohol. The invention further relates to an alkyl polyglycoside obtainable by said process.

Claims

1.-12. (canceled)

13. A process for the preparation of an alkyl polyglycoside comprising the step of mechanically treating a polysaccharide in the presence of an acid and a hydrophobic alcohol, wherein the mechanical treatment is effected by grinding, extruding or kneading and wherein the hydrophobic alcohol is a linear or branched C.sub.6-C.sub.22 alkanol, and wherein the molar ratio of the hydrophobic alcohol to the monomeric units of the polysaccharide is from 1:10 to 1:1.

14. The process according to claim 13 where the acid is contacted with the polysaccharide before or during the mechanical treatment.

15. The process according to claim 13 where the mechanical treatment is effected by grinding which is made by swing mills, stirred mills, stirred-media mills, vibration mills, agitator mills, agitator ball mills, hammer mills or ball mills.

16. The process according to claim 13 where the mechanical treatment is made at a reaction temperature of 0 to 300° C.

17. The process according to claim 13 where the mechanical treatment is made for 1 min to 12 hours.

18. The process according to claim 13 where the polysaccharide has a residual moisture content of less than 20 wt %.

19. The process according to claim 13 where the acid has a pKs of below 2.

20. The process according to claim 13 where the acid is selected from the group consisting of sulfuric acid, hydrochloric acid, sulphur dioxide, sulphur trioxide, phosphoric acid, phosphotungstic acid, halo-alkanecarboxylic acid, benzenesulfonic acids and derivatives thereof, methanesulfonic acid, oxalic acid and nitric acid.

21. The process according to claim 13 where the acid is contacted with the polysaccharide before the mechanical treatment to prepare an acid impregnated polysaccharide.

22. The process according to claim 21 where the acid impregnated polysaccharide is obtained by treating the polysaccharide with an acid in an organic solvent.

23. The process according to claim 22 where the organic solvent is water, C.sub.1-C.sub.22 alkanols, alkyl ether, C.sub.4-18 alkanes, supercritical carbon dioxide, dichloromethane, tetrahydrofurane, ethyl acetate, methyl acetate or acetone.

24. The process according to claim 13 where the polysaccharide is derived from starch, cellulose, hemicellulose or guar.

Description

EXAMPLES

Example 1—Impregnated α-cellulose

[0037] Impregnation:

[0038] In a one liter one-neck flask 3.1 g sulfuric acid (96%) was dissolved in 300 g methanol. After adding 33 g α-cellulose (solid content: 93.3%, degree of polymerization about 500 to 700, commercially available from Sigma-Aldrich GmbH, Germany) to the acidic methanol solution, the suspension was stirred at room temperature for an hour. The solvent was evaporated at 50° C. and 10 mbar using a rotary evaporator. The residue was homogenized by mortar and pistil.

[0039] A) Mechanical Treatment with Cool Down

[0040] 4 g of the acid impregnated cellulose and 0.5 g 1-octanol were filled in a 25 ml tungsten carbide (WC) grinding beaker. The mixture was milled together with a 15 mm diameter WC-ball at 30 Hz for overall 4 h by Retsch MM400. After every hour, the mixture was allowed to cool down for 30 min. The residue was analyzed by .sup.1H-NMR (in D.sub.2O) and MALDI-MS, which confirmed the octylization of the cellulose.

[0041] B) Mechanical Treatment without Cool Down

[0042] 4 g of the acid impregnated cellulose and 0.5 g 1-octanol were filled in a 25 ml tungsten carbide (WC) grinding beaker. The mixture was milled without interruption together with a 15 mm diameter WC-ball at 30 Hz for overall 4.5 h by Retsch MM400. The residue (Sample B) was analyzed by .sup.1H-NMR (in D.sub.2O) and MALDI-MS, which confirmed the octylization of the cellulose.

[0043] MALDI(+)-MS Analysis

[0044] The MALDI(+)-MS analysis of the reaction products of was made on a Bruker UltrafleXtreme TOF/TOF, Reflectron-Mode. Sample preparation: 6 μL of the aqueous sample solution were mixed with a spatula tip of 2,5-Dihydroxybenzoic acid (DHB) and 1 μL aq. NaCl solution using mortar and pistil. Peaks for the following structures (FIG. 3) were detected: Octylpolyglycoside, methylpolyglycoside and polyglycoside. Tables 1 and 2 summarize the peaks detected for the respective species for Example 1 A and 1 B.

##STR00001##

TABLE-US-00001 TABLE 1 Detected MS-signals of Example 1 A m/z m/z m/z (Octylpolygycoside + (Methylpolyglycoside + (Polyglycoside + n Na.sup.+) Na.sup.+) Na.sup.+) 1 315 217 203 2 477 379 365 3 639 541 527 4 801 703 689 5 963 865 851 6 1125 1027 1013 7 1287 1189 1175 8 1450 1351 1337 9 1612 1513 1499 10 1774 1676 1661 11 1936 1838 1824 12 2098 2000 1986 13 2260 2162 2148 14 — 2324 — 15 — 2486 —

TABLE-US-00002 TABLE 2 Detected MS-signals of Example 1 B m/z m/z m/z (Octylpolygycoside + (Methylpolyglycoside + (Polyglycoside + n Na.sup.+) Na.sup.+) Na.sup.+) 1 315 217 203 2 477 379 365 3 639 541 527 4 801 703 689 5 963 865 851 6 1125 1027 1013 7 1287 1189 1175 8 1450 1351 1337 9 1612 1513 1499 10 1774 1676 1661 11 1936 1838 1824 12 2098 2000 1986 13 2260 — 2148 14 — 2324 2310 15 — — — 16 — 2648 —

[0045] Interfacial Properties

[0046] The surface tensions of solutions of the Examples 1A and 1B in distilled water were determined using the Wilhelmy plate method. The crude products of the examples were purified from unreacted alcohols by washing with chloroform. After drying the residue, the surface tension was measured. The results are summarized in Table 3. The results showed that the reaction products of Example 1 A and 1 B display surface activities.

TABLE-US-00003 TABLE 3 Compound Concentration T Surface Tension Distilled Water — 25° C. 72 mN/m Example 1 A 1 g/L 25° C. 40.0 mN/m Example 1 B 1 g/L 25° C. 42.3 mN/m

Example 2—Impregnated Straw

[0047] Impregnation

[0048] In an 800 ml beaker 6.8 g sulfuric acid (96%) was dissolved in 280 g methanol. After adding 19.6 g cutted straw (from Germany) to the acidic methanol solution, the mixture was stirred at room temperature for an hour. The suspension was filtered off and the wet residue was dried at 50° C. and 50 mbar for 3 h. The residue was homogenized by mortar and pistil.

[0049] Mechanical Treatment

[0050] 2 g of acid impregnated straw were filled in a 25 ml tungsten carbide (WC) grinding beaker and was milled with a 15 mm WC-ball at 30 Hz for 10 min by Retsch MM400. Additional 2 g of acid impregnated straw were filled and was milled for further 60 min at 30 Hz. To the milled straw 1 g of 1-octanol/H.sub.2SO.sub.4-mixture (95/5, w/w) were filled and the mixture was milled for 60 min. The paste-like residue was suspended in chloroform for an hour and was filtered off. After drying at 50° C. and 50 mbar for 2 h, the residue was analyzed by .sup.1H-NMR (in D.sub.2O/NaOD) and MALDI-MS, which confirmed the octylization of the straw.

[0051] The surface tension of solution in distilled water was determined using the Wilhelmy plate method. The result of σ (1 g/L, 25° C.)=45 mN/m showed that the reaction product displays surface activity.

Example 3—Impregnated α-Cellulose

[0052] Impregnation

[0053] In an 800 ml beaker 6.6 g sulfuric acid (96%) was dissolved in 300 g methanol. After adding 33 g α-cellulose (as described in Example 1) to the acidic methanol solution, the mixture was suspended at room temperature for an hour. The suspension was filtered off and the wet residue was dried at 50° C. and 30 mbar for 3 h. The residue was homogenized by mortar and pistil.

[0054] A) Mechanical Treatment (No Additional Alcohol)

[0055] 4 g of the acid impregnated cellulose were filled in a 25 ml tungsten carbide (WC) grinding beaker. The mixture was milled with a 15 mm diameter WC-ball at 30 Hz for 90 min by Retsch MM400. The residue was analyzed by .sup.1H-NMR (in D.sub.2O) and MALDI-MS. Peaks for the following structures were detected (cf. Table 4): Methylpolyglycoside and polyglycoside.

TABLE-US-00004 TABLE 4 Detected MS-signals m/z m/z n (Methylpolyglycoside + Na.sup.+) (Polyglycoside + Na.sup.+) 1 217 203 2 379 365 3 541 527 4 703 689 5 865 851 6 1027 1013 7 1189 1175 8 1351 1337 9 1513 1499 10 1676 1661 11 1838 1824 12 — 1986 13 2162 2148 14 2324 2310 15 2486 — 17 2810 —

[0056] B) Mechanical Treatment with Additional Octanol

[0057] 4 g of milled cellulose from Example 3 A and 1 g of 1-octanol/H.sub.2SO.sub.4-mixture (90/10, w/w) were filled in a 25 ml tungsten carbide (WC) grinding beaker. The mixture was milled with a 15 mm diameter WC-ball at 30 Hz for overall 4 h by Retsch MM400. After every hour, the mixture was allowed to cool down for 30 min. The crude product was purified from unreacted alcohols by washing with chloroform. After drying the residue, the product was analyzed by .sup.1H-NMR (in D.sub.2O) and MALDI-MS. Peaks for the following structures were detected: Octylpolyglycosid, methylpolyglycoside and polyglycoside.

[0058] Table 5: Detected MS-signals

TABLE-US-00005 TABLE 5 Detected MS-signals m/z m/z m/z (Octylpolygycoside + (Methylpolyglycoside + (Polyglycoside + n Na.sup.+) Na.sup.+) Na.sup.+) 1 315 217 203 2 477 379 365 3 639 541 527 4 801 703 689 5 963 865 851 6 1125 1027 1013 7 1287 1189 1175 8 1450 1351 1337 9 1612 1513 1499 10 1774 1676 1661 11 1936 1838 1824 12 — 2000 1986 13 — 2162 2148 14 — — 2310

[0059] C) Mechanical Treatment without Impregnation

[0060] 4 g of α-cellulose (solid content: 93.3%) and 1 g of 1-octanol/H.sub.2SO.sub.4-mixture (80/20, w/w) were filled in a 25 ml tungsten carbide (WC) grinding beaker. The mixture was milled with a 15 mm diameter WC-ball at 30 Hz for overall 4 h by Retsch MM400. After every hour, the mixture was allowed to cool down for 30 min. The crude product was purified from unreacted alcohol by washing with chloroform. After drying the residue, the product was analyzed by .sup.1H-NMR (in D.sub.2O) and MALDI-MS. Peaks for the following structures were detected: Octylpolyglycoside and polyglycoside.

TABLE-US-00006 TABLE 6 Detected MS-signals m/z m/z n (Octylpolygycoside + Na.sup.+) (Polyglycoside + Na.sup.+) 1 315 203 2 477 365 3 639 527 4 801 689 5 963 851 6 1125 1013 7 1287 1175 8 1450 1337 9 1612 1499 10 1774 1661 11 1936 1824 12 — 1986 13 — 2148 14 — 2310 15 — 2472 16 — 2634

[0061] Interfacial Properties

[0062] The surface tensions of solutions of the examples 3 A, B and C in distilled water were determined using the Wilhelmy plate method. The results are summarized in Table 7. The results showed that the reaction products display surface activites.

TABLE-US-00007 TABLE 7 Compound Concentration T Surface Tension Distilled Water — 25° C. 72 mN/m Example 3 A 1 g/L 25° C. 71.8 mN/m Example 3 B 1 g/L 25° C. 45.8 mN/m Example 3 C 1 g/L 25° C. 47.6 mN/m

Example 4—Without Impregnation

[0063] The α-cellulose was the same as in Example 1. The maize starch was commercially available from Roquette GmbH, Germany with a solid content of 86.5 wt %. Before milling, the polysaccharide as listed in was dried at 100° C. and 50 mbar for 3 h. After drying, the polysaccharide and acidic dodecanol solution were filled in a 25 ml tungsten carbide (WC) grinding beaker. The mixture was milled with a 15 mm WC-ball at 30 Hz for overall 4 h by Retsch MM400. After every hour, the mixture was allowed to cool down for 15-30 min. The crude product was purified from unreacted alcohols by washing with chloroform.

[0064] After drying the residue, the product was analyzed by .sup.1H-NMR (in D.sub.2O) and MALDI-MS. Peaks for the following structures were detected: Dodecylpolyglycoside and polyglycoside. The recipes are listed in Table 8.

TABLE-US-00008 TABLE 8 amount polysac- polysac- amount acid- Compound charide charide Acidic dodecanol solution Example 4 A α-cellulose 4 g H.sub.2SO.sub.4/H.sub.2O 0.24 g (20/80, w/w) Example 4 B maize starch 4 g H.sub.2SO.sub.4/Dodecanol 0.53 g (20/80, w/w) Example 4 C α-cellulose 4 g H.sub.2SO.sub.4/Dodecanol 0.52 g (20/80, w/w) Example 4 D α-cellulose 4 g MeSO.sub.3H/Dodecanol 0.50 (30/70, w/w)

TABLE-US-00009 TABLE 9 Detected MS-signals of Ex. 4 A n m/z (Polyglycoside + Na.sup.+) 1 203 2 365 3 527 4 689 5 851 6 1013 7 1175 8 1337 9 1499 10 1661 11 1824 12 1986 13 2148 14 2310 15 2472 16 2634

TABLE-US-00010 TABLE 10 Detected MS-signals of Ex. 4 B m/z m/z n (Dodecylpolygycoside + Na.sup.+) (Polyglycoside + Na.sup.+) 1 371 203 2 533 365 3 695 527 4 857 689 5 1019 851 6 1182 1013 7 1344 1175 8 1506 1337 9 1668 1499 10 1830 1661 11 1992 1824 12 2154 1986 13 2316 2148 14 2478 2310 15 2640 2472 16 — 2634

TABLE-US-00011 TABLE 11 Detected MS-signals of Ex. 4 C m/z m/z n (Dodecylpolygycoside + Na.sup.+) (Polyglycoside + Na.sup.+) 1 371 203 2 533 365 3 695 527 4 857 689 5 1019 851 6 1182 1013 7 1344 1175 8 1506 1337 9 1668 1499 10 1830 1661 11 1992 1824 12 2154 1986 13 2316 2148 14 2478 2310 15 — 2472 16 — 2634

TABLE-US-00012 TABLE 12 Detected MS-signals of Ex. 4 D m/z m/z n (Dodecylpolygycoside + Na.sup.+) (Polyglycoside + Na.sup.+) 1 371 203 2 533 365 3 695 527 4 857 689 5 1019 851 6 1182 1013 7 1344 1175 8 1506 1337 9 1668 1499 10 1830 1661 11 1992 1824 12 2154 1986 13 2316 2148 14 2478 2310 15 — 2472 16 — 2634 17 — 2796

[0065] The surface tensions of solutions of the examples 4 A to D in distilled water were determined using the Wilhelmy plate method. The results are summarized in Table 13. The results showed that the reaction products of Example 4 display surface activities.

TABLE-US-00013 TABLE 13 Compound Concentration T Surface Tension Distilled Water — 25° C. 72 mN/m Example 4 A 1 g/L 25° C. 70.3 mN/m Example 4 B 1 g/L 25° C. 29.7 mN/m Example 4 C 1 g/L 25° C. 26.4 mN/m Example 4 D 1 g/L 25° C. 25.5 mN/m

Example 5—Polysaccharide from Straw or Wood

[0066] Following raw materials were used:

[0067] Straw: Native straw from Germany was cut in small pieces and 1.5-2 g were filled in a 25 ml stainless steel grinding beaker. The straw was milled with a 15 mm stainless steel ball at 30 Hz for 3 min by Retsch MM400. After repeating this procedure several times, the pre-milled straw was dried at 100° C. and 50 mbar for 3 h. The solid content was 88.5%.

[0068] Straw meal: Commercially available from Agri-Stro B.V., Netherlands as Hackselstroh dust-free. 2-2.5 g were filled in a 25 ml stainless steel grinding beaker. The straw meal was milled with a 15 mm stainless steel ball at 30 Hz for 5 min by Retsch MM400. After repeating this procedure several times, the pre-milled straw meal was dried at 100° C. and 50 mbar for 3 h. The solid content was 89.2%.

[0069] Birch, Pine or Beech (all from Germany): The stored wood was sawed, and the wood shavings were collected. The shavings were dried at 100° C. and 50 mbar for 3 h. The solid content of the appropriate wood was 82.9% for birch, 85.7% for pine and 87.0% for beech.

[0070] Straw (A), straw meal (B), wood shavings from birch (C), pine (D) and beech (E) were used. The dried residue and the acidic dodecanol solution were filled in a 25 ml tungsten carbide (WC) grinding beaker. The mixture was milled with a 15 mm WC-ball at 30 Hz for overall 4 h by Retsch MM400. After every hour, the mixture was allowed to cool down for 15-30 min. The crude product was purified from unreacted alcohols by washing with chloroform. After drying the residue, the soluble part of the product was analyzed by .sup.1H-NMR (in D.sub.2O). The recipes are listed in table 6. The surface tensions of solutions in distilled water were determined using the Wilhelmy plate method. The results are summarized in Table 14 and 15. The results showed that the reaction products display surface activities.

TABLE-US-00014 TABLE 14 amount polysac- polysac- amount acid- Compound charide charide Acidic dodecanol solution Example 5 A straw 4 g H.sub.2SO.sub.4/Dodecanol 0.50 g (20/80, w/w) Example 5 B straw meal 4 g H.sub.2SO.sub.4/Dodecanol 0.50 g (30/70, w/w) Example 5 C birch 4 g H.sub.2SO.sub.4/Dodecanol 0.53 g (30/70, w/w) Example 5 D pine 4 g H.sub.2SO.sub.4/Dodecanol 0.53 g (30/70, w/w) Example 5 E beech 4 g H.sub.2SO.sub.4/Dodecanol 0.52 g (30/70, w/w)

TABLE-US-00015 TABLE 15 Compound Concentration T Surface Tension Distilled Water — 25° C. 72 mN/m Example 5 A 1 g/L 25° C. 44 mN/m Example 5 B 1 g/L 25° C. 49.6 mN/m Example 5 C 1 g/L 25° C. 41.1 mN/m Example 5 D 1 g/L 25° C. 40.4 mN/m Example 5 E 1 g/L 25° C. 40.7 mN/m

Example 6: Polysaccharide from Pulp

[0071] Washed pulp from industrial paper production based on spruce from Sweden (pulp obtained after the refiner (8 bar, 170° C. in 12 inch disc refiner) and washing step) was dried at 100° C. and 50 mbar for 4 h. The solid content was 27.2%. 2 g of dried pulp was filled in a 25 ml tungsten carbide (WC) grinding beaker and was milled with a 15 mm WC-ball at 30 Hz for 5 min by Retsch MM400. Additional 2 g of dried pulp was filled and was milled for further 5 min at 30 Hz. To the milled pulp 0.52 g of H.sub.2SO.sub.4-/1-dodecanol mixture (30/70, w/w) were filled and the mixture was milled analog for overall 4 h. After every hour, the mixture was allowed to cool down for 15 min. The crude product was purified from unreacted alcohols by washing with chloroform. After drying the residue, the product was analyzed by .sup.1H-NMR (in D.sub.2O).

[0072] The surface tension of solution of in distilled water were determined using the Wilhelmy plate method. The result of 6 (1 g/L, 25° C.)=44.3 mN/m showed that the reaction product displays surface activity.

Example 7: Hexadecyl- and Octadecylpolyglycosid

[0073] Before milling, α-cellulose as used in Example 1 was dried at 100° C. and 50 mbar for 3 h to a solid content of 93%. 4 g of the dried cellulose and 0.70 g of C16/C18-alcohol/H.sub.2SO.sub.4-mixture (70/30, w/w) (Hydroxyl value for C16/C18-alcohol: 217.4 mg KOH/g) were filled in a 25 ml tungsten carbide (WC) grinding beaker. The mixture was milled with a 15 mm WC-ball at 30 Hz for overall 5 h by Retsch MM400. After every hour, the mixture was allowed to cool down for 30 min. The crude product was purified from unreacted alcohols by washing with chloroform. After drying the residue, the product was analyzed by .sup.1H-NMR (in D.sub.2O) and MALDI-MS. Peaks for the following structures were detected, see also Table 16: Polyglycoside, hexadecylpolyglycoside and octadecylpolyglycoside.

[0074] The surface tension of solution in distilled water was determined using the Wilhelmy plate method. The result of 6 (1 g/L, 25° C.)=43.8 mN/m showed that the reaction product displays surface activity.

TABLE-US-00016 TABLE 16 Detected MS-signals m/z m/z (Octadec- (Hexa- m/z ylpolygycoside + decylpolygycoside + (Polyglycoside + n Na.sup.+) Na.sup.+) Na.sup.+) 1 455 427 203 2 617 589 365 3 779 751 527 4 941 913 689 5 1104 1076 851 6 1266 1238 1013 7 1428 1400 1175 8 1590 1562 1337 9 1752 1724 1499 10 1914 1886 1661 11 2076 — 1824 12 2238 — 1986 13 — — 2148 14 — — 2310

Example 8: Behenylpolyglycoside

[0075] Before milling, α-cellulose as in Example 1 was dried at 100° C. and 50 mbar for 3 h. 4054 mg of the dried cellulose, 411 mg of behenyl alcohol (1-docosanol) and 156 mg MeSO.sub.3H were filled in a 25 ml tungsten carbide (WC) grinding beaker. The mixture was milled with a 15 mm diameter WC-ball at 30 Hz for overall 4 h by Retsch MM400. After every hour, the mixture was allowed to cool down for 30 min. The crude product was purified from unreacted alcohol by washing with chloroform. After drying the residue, the product was analyzed by .sup.1H-NMR (in D.sub.2O) and MALDI-MS. Peaks for the following structures were detected: Polyglycoside, behenylpolyglycoside. The surface tension of the solution in distilled water was determined using the Wilhelmy plate method. The result of 6 (1 g/L, 25° C.)=67.9 mN/in showed that the reaction product displays surface activity.

TABLE-US-00017 TABLE 17 Detected MS-signals m/z m/z n (Octadecylpolygycoside + Na.sup.+) (Polyglycoside + Na.sup.+) 1 511 203 2 673 365 3 835 527 4 997 689 5 1160 851 6 1322 1013 7 1484 1175 8 1646 1337 9 1808 1499 10 1970 1661 11 2132 1824 12 2294 1986 13 2148 14 2310