Studies On Lipase Synthesis Of Sucrose-Based Polymers And Application

Sucrose-based polymers mean that through different responses to lead to polymer molecular chain group and to form functional polymer material. Lipase receives much concern because of its universality and wide-adaptability of catalytic function. This paper adopts enzyme-enzyme method synthesis of polymer with sucrose in the main chain and enzyme-chemistry method synthesis of polymer with sucrose in the branch chain.First, studies on enzymatic synthesis of sucrose divinyladipate esters, which was prepared by using sucrose as the raw arterial and divinyladipate as the acryl donor of transesterification, catalyzed by Novozym-435 in non-aqueous(organic phase and reverse micelle system) with the Uniform Design method and the single factor method. The structure of SMVA, SDVA, and STVA were characterized by FTIR, HPLC, HPLC-MS, NMR and TLC. They confirmed that Novozym-435 acylation preferably occurrs on C-6, then C-6' and C-1'.1. In organic phase, the effects of different solvents, the water of content of organic solvent, the reaction temperature, enzyme concentration, and mole ratio of sucrose/divinyladipate on the yield of products were investigated. At last, the optimal process conditions and practical yield for synthesis of SMVA and SDVA were obtained respectively as follows: tert-Butyl alcohol, the water content was 0, the reaction temperature was 49℃, the enzyme concentration was 30 mg/mL, the mole ratio of sucrose/divinyladipate was 1:3.2, after reaction for 4 d, the yield of SMVA reached 13.69%; acetone, the water content was 0, the reaction temperature was 47.5℃, the enzyme concentration was 30 mg/mL, the mole ratio of sucrose/divinyladipate was 1 : 3.3, after reaction for 3 d, the yield of SDVA reached 28.82%.2. In reverse micelle system, the effects of different solvents, the reaction temperature, the water contentω₀, buffer pH, AOT concentration, and enzyme concentration on the yield of products were investigated. At last, the optimal process conditions and practical yield for synthesis of SMVA was obtained as follows: AOT / acetone as reverse micelle system, the reaction temperature was 50℃, the water contentω₀ was 12, buffer pH was 7.5, the AOT concentration was 125 mmol/L, and the enzyme concentration was 35 mg/mL, after reaction for 2 d in 200r/min, the yield of SMVA reached 64.42%.After getting polymerized sucrose ester, we adopts polycondensation of SDVA and 1,8-octanediol using Novozym-435, synthesis of polymer with sucrose in the main chain; and homopolymerization of SMVA using redox initiation system, synthesis of polymer with sucrose in the branch chain. The structure of polymer was characterized by FTIR and GPC. The results confirmed the homopolymerization of SMVA was successful. The polymers had high molecular weight and narrow distribution. Studies on initiated effect of different initiation, k₂S₂O₈ /FeSO₄ is the best, and contained high molecular weight and yield. The polymer containing sucrose was biodegradable by enzyme hydrolysis.The release property of sucrose-based polymers as Fenoprofen Calcium release carrier in artificial intestinal juice was preliminary explorated. After determination of dynamic dialysis method, Fenoprofen Calcium can release slowly in artificial intestinal juice in 12h. The slow release effect is good.