Study On The Preparation Of Amphipathic Starch And The Solubilization Properties Of Aggregates

In this paper, based on carboxymethyl groups with good water solubility and alkyl groups having hydrophobic association with the characteristics of the introduction of alkyl groups to the carboxymethyl starch molecules designed and synthesized a series of hydrophilic / hydrophobic compound starch improved thermal stability and improve the single modified carboxymethyl starch and nature of water. Detailed study of the nature of the reaction conditions for the solubilization degree of substitution of alkyl ester, alkyl esters of carboxymethyl starch solution properties and aggregates the best summary obtained esterification reaction solvent type, carboxymethyl starch alkyl ester-based surface tension properties of the law in an aqueous solution, the concentration range of critical aggregation rule of rutin and solubilization of insoluble material, expanding the applications of starch derivatives.Firstly, chloroacetic acid as etherification agent, was synthesized by etherification carboxyl group-containing anionic carboxymethyl starch(CMS), and then the carboxymethyl starch hydrophobically modified by esterification, carboxymethyl starch was prepared alkyl esters. The introduction of hydrophobic group will affect the alkyl ester of carboxymethyl starch water-soluble, was prepared in DMSO low esterification degree of substitution(less than 0.1) the alkyl ester of carboxymethyl starch can be dissolved in water.By FT-IR of carboxymethyl starch alkyl esters prepared were characterized, TG were analyzed thermal stability, XRD analysis were crystalline, HPLC determination of molecular weight products.For the synthesis of a series of alkyl esters of carboxymethyl starch, a detailed study of the surface tension of the law, CAC scope and size distribution. Carboxymethyl starch on the surface tension of the solution was measured alkyl esters found in similar esterification degree of substitution(0.12) premise, the longer the length of the carbon chain alkyl, lower the surface tension, the corresponding CAC also lower. The critical aggregation concentration of approximately in the range is 2 ~10 mg / m L. By pyrene fluorescence probe method accurately measured(DSCMS = 1.028, DSalkyl = 0.034) carboxymethyl starch caprylate,carboxymethyl starch and carboxymethyl starch laurate palmitate CAC was 2.1 mg / mL, 1.8mg / mL and 1.5 mg / mL. Carboxymethyl starch laurate were particle size analysis, particle size distribution range 150-250 nm, the concentration increases aggregate diameter also becomes large.Select similar esterification degree of substitution of carboxymethyl starch alkyl ester detailed study of the nature and impact of solubilization of insoluble material factors rutin(degree of substitution, concentration, temperature, pH, etc.). Carboxymethyl starch alkyl esters form micelles in aqueous solution, gathered in hydrophobic micro area play a key roleon the solubilization rutin, hydrophobic micro area space, the greater the number the more,the greater the solubilization effect good.The results showed that the degree of substitution in the esterification 0.034, solution concentration of 41 mg/mL, the solution temperature is 25 ?,pH = 10.5 Octanoate when carboxymethyl starch, carboxymethyl starch laurate, palmitate on carboxymethyl starch solubilizing amount of rutin were 3.05 mg/mL, 4.02 mg/mL, 4.52mg/m L.