PARTIALLY SAPONIFIED RICE BRAN WAX OXIDATES

Abstract

The invention relates to partially saponified rice bran wax oxidates, to a process for the production of these products and to their use for agriculture or forestry purposes, as an additive in plastics processing, in care products, in printing inks and/or in paints.

Claims

1. A process for producing a partly saponified rice bran wax oxidate (V), comprising the steps of: i) providing a rice bran wax (R) containing less than 20% by weight, based on the total weight of the rice bran wax (R), of polyesters formed from polyhydric alcohols and aliphatic carboxylic acids having 8 to 20 carbon atoms; ii) providing a mixture (M) of chromium trioxide and sulfuric acid; iii) performing the oxidation of the rice bran wax (R) by reacting the rice bran wax (R) with the mixture (M) while stirring and while stirring at a temperature of 90 to 150? C., in order to obtain a rice bran wax oxidate (O); iv) ending the reaction and leaving the reaction mixture obtained in step iii) to stand until the organic phase has separated from the aqueous phase; v) separating off the organic phase; vi) optionally removing residues containing chromium compounds from the organic phase in order to obtain the rice bran wax oxidate (O) in purified form; vii) optionally repeating the sequence of steps ii) to vi) using the rice wax oxidate (O), optionally in purified form, rather than the rice bran wax (R); and viii) saponifying the rice bran wax oxidate (O), optionally in purified form, by reacting it with a basic salt, preferably a basic metal salt, especially selected from alkali metal hydroxides and alkaline earth metal hydroxides, wherein no alcohol component is added to the reaction mixture in step iii) to step viii), preferably in all steps of the entire process.

2. The process according to claim 1, wherein the oxidation in step iii) is performed over a period of 2 to 9 hours.

3. The process according to claim 1, wherein the sequence of steps ii) to vi) is repeated once to four times, and wherein the rice bran wax oxidate (O) obtained in step vii) or optionally viii), optionally in purified form, is added in place of the rice bran wax (R).

4. The process according to claim 1, wherein the weight ratio of the total amount of chromium trioxide used to rice bran wax (R) used is from 1:1 to 3:1, preferably from 1.1:1 to 3:1.

5. The process according to claim 1, wherein the step of removing residues containing chromium compounds is conducted in step vi) and comprises the washing of the organic phase with an aqueous solution of oxalic acid and/or sulfuric acid.

6. The process according to claim 1, wherein the step of removing residues containing chromium compounds is conducted in step vi) and comprises the washing of the organic phase with water.

7. The process according to claim 1, wherein the step of removing residues containing chromium compounds is conducted in step vi) and comprises centrifuging of the organic phase.

8. The process according to claim 1, wherein the concentration of chromium trioxide in the mixture (M) is from 50 to 200 g/l.

9. The process according to claim 1, wherein the stirrer speed in step iii) is between 100 and 500 rpm.

10. The process according to claim 1, wherein the saponifying in step viii) is performed over a period of 0.5 to 10 h at a temperature of 90 to 150? C.

11. The process according to claim 1, wherein no additional oxidation promoters are added to the reaction mixture in any of the steps.

12. A partly saponified rice bran wax oxidate (V) comprising the following components: a) 30% to 85% by weight, based on the total weight of the partly saponified rice bran wax oxidate (V), of genuine esters having 42 to 64 carbon atoms; b) 0% to 70% by weight, preferably 10% to 70% by weight, based on the total weight of the partly saponified rice bran wax oxidate (V), of salts of aliphatic carboxylic acids having 8 to 36 carbon atoms; and c) 0% to 5% by weight, especially 0% to 3% by weight, based on the total weight of the partly saponified rice bran wax oxidate (V), of polyesters formed from polyhydric alcohols and aliphatic carboxylic acids having 22 to 36 carbon atoms.

13. The partly saponified rice bran wax oxidate (V) according to claim 12, comprising the following components: a) 30% to 85% by weight, based on the total weight of the partly saponified rice bran wax oxidate (V), of genuine esters having 42 to 64 carbon atoms; b) 10% to 40% by weight, based on the total weight of the partly saponified rice bran wax oxidate (V), of salts of aliphatic carboxylic acids having 8 to 36 carbon atoms; c) 0% to 5% by weight, especially 0% to 3% by weight, based on the total weight of the partly saponified rice bran wax oxidate (V), of polyesters formed from polyhydric alcohols and aliphatic carboxylic acids having 22 to 36 carbon atoms; d) 5% to 40% by weight, based on the total weight of the partly saponified rice bran wax oxidate (V), of free aliphatic monocarboxylic acids having 8 to 36 carbon atoms, of which preferably not more than 10% by weight, based on the total weight of the partly saponified rice bran wax oxidate (V), is lignoceric acid; e) 0% to 10% by weight, preferably 0.1% to 5% by weight, based on the total weight of the partly saponified rice bran wax oxidate (V), of free aliphatic alcohols having 24 to 36 carbon atoms; f) 0% to 5% by weight, preferably 0.1% to 5% by weight, based on the total weight of the partly saponified rice bran wax oxidate (V), of free aliphatic dicarboxylic acids having 10 to 30 carbon atoms; and g) 0% to 15% by weight, especially 0.1% to 10% by weight, based on the total weight of the partly saponified rice bran wax oxidate (V), of natural constituents of rice bran wax other than a) to f).

14. A partly saponified rice bran wax oxidate (V) prepared by a process according to claim 1.

15. Use of the partly saponified rice bran wax oxidate (V) according to claim 12 for agricultural or forestry purposes, as additive in plastics processing, in care products, in printing inks and/or in paints.

16. The partly saponified rice bran wax oxidate (V) according to claim 14, comprising the following components: a) 30% to 85% by weight, based on the total weight of the partly saponified rice bran wax oxidate (V), of genuine esters having 42 to 64 carbon atoms; b) 0% to 70% by weight, preferably 10% to 70% by weight, based on the total weight of the partly saponified rice bran wax oxidate (V), of salts of aliphatic carboxylic acids having 8 to 36 carbon atoms; and c) 0% to 5% by weight, especially 0% to 3% by weight, based on the total weight of the partly saponified rice bran wax oxidate (V), of polyesters formed from polyhydric alcohols and aliphatic carboxylic acids having 22 to 36 carbon atoms.

Description

EXAMPLES 1 TO 9

[0108] A 3 l reaction vessel equipped with stirrer, temperature sensor, dropping funnel and reflux condenser was initially charged with the amount of chromium trioxide in sulfuric acid (concentration: 100 g CrO.sub.3/I) specified in Table 4, and heated to 100? C.

[0109] Subsequently, molten (90? C.) rice bran wax was added in portions in the raw state. The temperature of the reaction mixture was adjusted to 110? C., and the reaction mixture was stirred with a precision glass stirrer at about 200 rpm for 8 h. The heating and stirring were switched off. As soon as the phases had separated, the aqueous phase was separated off.

[0110] This operation was repeated once in Examples 5 to 7 and twice in Example 8 (with the amounts of chromium trioxide in sulfuric acid specified in each case), using the rice bran wax oxidate from the previous operation in each case rather than the rice bran wax.

[0111] The organic phase was freed of chromium residues by washing with an aqueous solution of oxalic acid and sulfuric acid and then by washing with water, discharged into warm centrifuge bottles and centrifuged.

[0112] In a 1 l reaction vessel equipped with stirrer, temperature sensor, dropping funnel and reflux condenser, the appropriate rice bran wax oxidate was melted under a nitrogen atmosphere and admixed with the appropriate amount of Ca(OH).sub.2 (Examples 1 to 8) or aqueous NaOH (Example 9; 9 g of NaOH in 100 ml of water).

[0113] The reaction mixture was stirred until the desired acid number had been attained and then the reaction mixture was pressure-filtered in the hot state. In Example 9, the reaction mixture is additionally dried to constant mass in a vacuum drying cabinet (Example 9).

[0114] The chain length distribution measured for Example 2 is shown in FIG. 1.

TABLE-US-00004 TABLE 4 (methods, abbreviations and units in Table 1) Example 1 2 3 4 5 6 7 8 9 RBW 1 100 g 100 g 100 g 100 g 100 g 100 g 100 g 100 g 100 g Oxidation CrO.sub.3/ 1.2 | 1.5 | 1.5 | 1.5 | 1.0 | 1.0 | 1.0 | 1.0 | 1.0 | H.sub.2SO.sub.4 0.6 | 0.6 | 1.0 | 0.8 | 0.8 | 0.6 | 0.6 | Reaction 8 8 8 8 8 8 8 8 8 time [h] 8 8 8 8 8 8 8 Reaction 110 110 110 110 110 110 110 110 110 temperature [? C.] AN 45.7 51.2 51.2 51.2 71.1 71.1 89.6 123.9 123.9 (oxidate) Saponification Ca(OH).sub.2 5.1 g 3.1 g 3.7 g 5.0 g 5.0 g 6.1 g 8.9 g 8.6 g NaOH 9.0 g Reaction 2 2 2 4 3 4 6 1 1 time [h] Reaction 130 130 130 130 130 130 130 130 110 temperature [? C.] AN 4.1 14.9 8.1 5.6 19.0 12.0 13.7 8.6 2.0 SN 65 79 72 52 70 68 49 47 23 DP 103 108 111 120 106 140 135 133 MP 79.6 82.3 81.9 81.7 81.4 81.8 80.9 106.8 81.0 EF ?162 ?209 ?208 ?200 ?197 ?194 ?186 ?173 ?186 TGA 2.30/ 4.37/ 1.66/ 1.45/ 2.31/ 3.39/ 6.86/ 3.01/ 2.54/ 7.76 7.98 5.09 4.88 5.34 12.55 19.23 8.45 7.31 Viscosity 42 48 880 1,160 333 5,447 [mPas] at 120? C. CIE L* 89.24 93.50 91.68 86.60 91.18 90.94 86.20 83.1 94.55 CIE a* 0.95 0.68 0.64 0.75 0.48 0.32 1.08 0.90 0.46 CIE b* 9.37 4.20 4.39 12.24 6.83 4.98 11.47 15.40 12.16 NPI 1 1 1 1 1 1 1 1 1