Amylopectin, ester derivatives

Ester derivatives of cellulose, chitin, dextran, amylose, and amylopectin were prepared utilizing the acid chloride derivatives described in Part B of the Experimental Section. 

Table I lists physical data for a number of the carbamate and ester derivatives of cellulose, chitin, amylose, amylopectin, and dextran synthesized as described in the Experimental Section. The solubility of the polysaccharide starting materials as well as that of the produced derivatives allows for macromolecular characterization through techniques including UV, NMR, IR, high pressure liquid chromatography, etc.

Starch (amylose and amylopectin) hydrolysis along with ester-fication, etherification or oxidation have been previously discussed as available methods for producing starch derivatives with improved water dispersibilities and reduced retrogradation potential (, ). Since oxidative and hydrolytic reactions are simple, easily controlled chemical modifications, starch-derived polymers made by hydrolysis alone or oxidative and hydrolytic processes were developed and tested. 

Al-glycosyl derivatives of, 233 Amylopectins, 281-283, 310 nitrate ester, 341 potato, 273 nitration of, 340... 

Palmitoyl hydroxypropyltrimonium amylopectin/glycerin crosspolymer Definition Palmitic acid ester of a polymer of the hydroxypropyltrimonium deriv. of amylopectin crosslinked with glycerin Uses Skin conditioner in cosmetics Palmitoyl keratin amino acids Definition Condensation prod, of palmitic acid chloride and keratin amino acids Uses Antistat, surfactant, foaming agent, wetting agent for cosmetics, hair care, skin care... 

Starch esters are synthesized by reaction of a carboxylic acid or an acyl chloride or an acid anhydride with the hydroxyl groups of amylose or amylopectin chains. As in the case of cellulose derivatives, there are organic and inorganic esters depending on the origin of the substituent. 

Starch esters represent an important class of starch derivates and have been recently reviewed by Tessler and Billmers [63]. Starch esters can be produced by an aqueous process, at low alkalinity, under controlled pH, and low temperature reactions usually reaching a fairly low degree of substitution (DS<0,2) [64]. Starch acetates with a DS of 2.4 or higher are not biodegradable, like cellulose, while intermediate DS acetate would be easily biodegradable [63,31,32]. Most commercially used starch derivates have a DS less than 0.2 [60]. Pure amylose starch is considered the most desirable precursor for starch-ester based thermoplastics since amylopectin has an adverse impact on mechanical and physical properties of these derivatives [64]. 

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