Method for producing compound modified starch

Abstract

The invention relates to the field of chemical adhesive, in particular to a method for producing compound modified starch. The method solves problems that existing modified starch is treated by a modification method mostly, is narrow in application range and poor in practicality, and the like. The method includes steps of (1), mixing starch with water to blend into starch slurry; (2), adding sodium hypochlorite into the starch slurry to perform oxidization reaction; (3), adding dimethylol urea which is a crosslinking agent into the mixture to perform crosslinking reaction; (4), regulating the pH (potential of hydrogen) value of the slurry to range from 7.5 to 8.5 after the reaction; and (5), performing wet screening and washing for the slurry obtained in the step (4), and then feeding the slurry into a pre-gelatinization drying machine to dehydrate and dry. Carboxyl is added into starch molecules during reaction, so that the starch molecules have the characteristics of hydrophilicity and lipophilicity and have good emulsification and dispersion effects. In addition, the dimethylol urea is added into the starch molecules for performing the crosslinking reaction, so that the compound modified starch has the advantages of stable viscosity, high water absorption, shearing resistance and alkali resistance, good film-forming property and the like, and can be applied to various fields.

Description

technical field

[0001] The invention relates to the field of chemical adhesives, in particular to a method for producing compound modified starch. Background technique

[0002] Although the history of starch application in my country is very long, due to various reasons, the research and development, production and application of starch and modified starch in my country are quite backward. Until 1978, the annual output of starch in China was only 280,000 tons, and modified starch was almost blank. At the end of the 1990s, the improvement of the national food situation provided the possibility for the development of starch and modified starch, and the economic development and the improvement of various product grades made it necessary. After more than 30 years of development, the current national starch production is 3 million tons, or 2.5 kilograms per capita, but there is still a big gap compared with Japan's per capita 25 kilograms and the United States' per capita 66 kilog...