| 摘要 |
This patent describes the derivatives of hemicellulose closed to the type of (1->4)-beta-D-xylan with the structural units represented by formulas (I) and (II) and/or (II) where R1 and R2, which can be the same or different, mean hydrogen or the group with a general formula (IV), where X means hydroxyl, dihydrogenphosphate, hydrogensulphate, chloride or acetate anion, R3 means the structural unit closed to 4-O-methyl-aplpha- -D-glucoronic acid with a general formula (V), in which Y means hydrogen, sodium or potassium, R4 means the unit closed to alpha-L-arabinofuranose with a formula (VI), while the average degree of polymerisation closed to (1->4)-beta-D-xylan is 20 up to 200. The derivatives of hemicellulose are prepared based on that principle, that in the first stage hemicellulose closed to the type of (1->4)-beta-D-xylan with the structural unit represented by the formula (VII) and (II) and / or (III) are being activated wit 1 up to 25 weight percent water solution of alkaline metal hydroxide at the temperature of 15 up to 25 Celsius degrees, for 30 up to 60 minutes, in the second stage they are undertaken to alkylation with the use of 3-chlorine-2-hydroxypropylmethylammonium chloride, at the temperature of 30 up to 80 Celsius degrees, for 2 up to 6 hours, while the molar ratio closed to hemicellulose : alkaline metal hydroxide is 1: 0,2 up to 3: 0,1 up to 2 a dialysed and dried. The prepared product can be applied as the flocculating agent, when talking about water purification and it also can be used as the auxiliary additive in the production of paper.
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