Лако-красочные материалы — производство

Acid modification of starch is achieved by heating the starch to 49-54° C with small amounts of aqueous mineral acid, followed by neutralization with base. The acid acts mainly on the amorphous regions of the starch granules, leaving the x-ray and birefrin­gence patterns of the crystalline regions essentially unchanged. Dried acid-modified starch appears very similar to its unmodified counterpart; however, upon heating a suspension to the gelation temperature, the differences become obvious. The acid modified starch tends to give a much thinner solution at the same solids content when compared to unmodified starch. This makes the modified starch useful in applications that require a higher solids content.