Reactive printing gum and preparation method thereof

The invention discloses a reactive printing gum and a preparation method thereof. The preparation method comprises the following steps: carrying out an alkaline reaction on a mixture of potato starch and corn starch under the catalytic action of a molecular sieve solid alkali; after the alkaline reaction, sequentially adding an oxidant and an etherifying agent into the reaction system of the alkaline reaction to carry out an oxidation reaction and an etherification reaction sequentially; after the etherification reaction, neutralizing the product until the pH value is 5-8 so as to obtain the reactive printing gum; the molecular sieve solid alkali is obtained through ion exchange between a crystal type aluminosilicate and an alkali metal kation, the bearing capacity of the alkali metal kation is 2%-30%. According to the invention, the solid alkali adopting the molecular sieve as a carrier is used for alkalifying and also provides good catalytic activation for the reaction, so that the production efficiency is increased, and the uniformity of the substitution degree is guaranteed while high substitution degree of the product is guaranteed; meanwhile, the solid catalyst has more advantages compared with a liquid alkali, for example, fewer post-treating problems, easier separation and recycling of product, catalyst, and solvent, environment friendliness, economy, and the like.