TH41388A - Method for producing solutions of highly cationic starch. - Google Patents

Abstract

DC60 (01/12/42) This invention relates to a method for the production of starch solutions with a high cation equivalent value (along with a DS of 0.1-1.0). Starch is cationized with good results. Oxidized starch is slurried into a suspension of approximately 10-80% solid content in an aqueous mixture of cationizing agents. 2,3-epoxypropyltrimethylammonium chloride or an equivalent chlorohydrin-type cationizing agent is used at approximately 90-1100 g per starch solid, and the catalyst is added to the slurry. The reaction is carried out with a high solid content of 40-80%, with an optimal 50-60%, in at least two steps. The first step, in which the temperature is maintained at approximately 5-40 °C, and the second step... The temperature was approximately 70-180 °C. This invention relates to a method for producing starch solutions with a high cation equivalent value (along with a DS of 0.1-1.0). Starch was cationized with good results. The oxidized starch was slurried into a suspension of approximately 10-80% solids in an aqueous mixture of cationizing agents. 2,3-epoxypropyltrimethylammonium chloride or an equivalent chlorohydrin-type cationizing agent was used at approximately 90-1100 g per starch solid, and the catalyst was added to the slurry. The reaction was carried out with a high solids content of 40-80%, with an optimal 50-60%, in at least two steps. The first step involved maintaining the temperature at approximately 5-40 °C, and the second step at approximately 70-180 °C.

Claims (10)

1. A method for preparing starch solutions with a high cation equivalent (with a DS value of 0.1-1.0) in which cationized starch is slurried into a suspension of approximately 10-80% solid solution in an aqueous mixture of cationizing agent. Approximately 90-1100 g of cationizing agent is used per kg of starch solid. A catalyst is added to the slurry, and the cationizing agent reacts with the starch. A characteristic feature of this method is that the reaction is carried out at a high solids content of 40-80% in at least two stages. In the first stage, the temperature is maintained at 5-40 °C, and in the second stage, the temperature is 70-180 °C. 2. The method conforming to claim 1 is characterized by the fact that the first-order reaction steps are carried out at a temperature of 15-35 °C and the amount of reaction solids is 40-80%. 3. The method conforming to claim 1 or 2 is characterized by the fact that the first-order reaction steps are carried out between 1 and 10 hours. 4. The method conforming to claim 3 is characterized by the fact that the first-order reaction steps are performed in a relative proportion of approximately 30-75% of the total reaction. 5. The method conforming to claim 1 is characterized by the fact that the second-order reaction steps are carried out at a temperature of 80-140 °C and the amount of reaction solids is 40-80%. 6. The method conforming to claim 5 is characterized by the fact that the temperature of the reaction mixture is raised for the execution of the second reaction step by applying a high energy density. 7. A method consistent with any of claims 4, 5, and 6 is characterized by the temperature of the reaction mixture being increased for the second reaction step by applying an energy density where the relative rate of reaction progress during the temperature increase step is 20-60%. 8. The method consistent with claim 7 is unique in that the cation reaction is completed at a de-icing in the third step, immediately following the second step. 9. A method consistent with any of the claims 1 through 8 is characterized by the use of alkali earth or alkali metal hydroxide catalysts in an amount of 1-4% of the starch volume. 10. The procedure consistent with claim 8 or 9 has the specific characteristic that the third step has been executed in less than 8 hours.