MIXED STARCH ESTERS AND THE USE THEREOF

摘要

This invention is directed to mixed esters of starch and to the method of preparing and the use of said starch esters which are derived from (a) low molecular weight hydrolyzed starch having a plurality of anhydroglucose units and (b) at least about 0.5 mole of acylating agent per anhydroglucose unit consisting of mono- and polycarboxylic acid anhydrides and acyl halides. These anionic esters of starch with average molecular weights ranging up to 100,000 are characterized as having a high degree of substitution, i.e. ranging up to 3.0 wherein at least about 0.1 of the total degree of substitution consist of ester groups having pendant carboxyl radicals derived from anhydrides of polycarboxylic acids.