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Molecular and material design of aliphatic polyesters with controlled biodegragradability

具有受控生物降解性的脂肪族聚酯的分子和材料设计

基本信息

批准号：
11217210
负责人：
KIMURA Yoshiharu
金额：
$ 31.1万
依托单位：
Kyoto Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research on Priority Areas
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2002
项目状态：
已结题

项目摘要

Various aliphatic polyesters have been synthyesized as biodegradable polymers thus far. Their biodegradability has been known to depend largely on the crystallinity as well as on the crystal size and morphology. In this research, various biodegradable polyesters having life-controlled degradability are designed and synthesized by ring-opening polymerization of new monomers and by well-controlled direct polycondensation.For example, glycolate and malate units were introduced into poly (3-hydroxybutyric acid) (PHB) to enhace the hydrolyzability of PHB and to have wide options for the functionalization of PHB. 12-Hydroxystearic acid (12HSA unti was also incorporated into poly (L-lactic acid) (PLLA) by ring-opening copolymerization of L-lactide and cyclic dimer of 12HSA in order to attain a soft PLLA derivative. Copolymerization of L-lactic acid with mandelic acid was also conducted to obtain glassy biodegradable copolymer with high glass transition temperature and increase degradability. … More Block copolymers of PLLA and poly (oxyethylene) (PEG) were prepared by the ring-opening copolymerization of PEG and L-lactide and dispersed into water to obtain core-shell nanoparticles. From these particles, a specific band structure was formed by the crystallization of the helical PLLA blocks. Sol-gel transition was found to occur on mixing the disperisions of the enationmeric A-B-A triblock copolymers, PLLA-PEG-PLLA and PDLA-PEG-PDLA. This transition was driven by the stereo-complexation of the PLLA and PDLA chains. The core-sheath bicomponent fiber consisting of poly (glycolic acid) (PGA) and PLLA as the core and sheath, respectively, was processed by melt-spinning. The fiber showed higher degradability than the single PLLA fiber.Enzymatic degradation of poly (butylene succinate) (PBS) and its derivative, poly (butylene succinate-co-terephthalate) (PBST) was studied by using a lipase originated from Pseudomonas cepacia. PBS and PBST was biodegraded by exo-type and endo-type scission of ester linkage, respectively. Less

迄今为止，各种脂肪族聚酯已被合成为可生物降解的聚合物。已知它们的生物降解性在很大程度上取决于结晶度以及晶体大小和形态。在本研究中，通过新单体开环聚合和控制良好的直接缩聚，设计和合成了各种具有生命可降解性的生物可降解聚酯。例如，在聚3-羟基丁酸（PHB）中引入乙醇酸和苹果酸，以提高PHB的水解能力，并为PHB的功能化提供了广泛的选择。通过l -丙交酯与12HSA环二聚体开环共聚，将12-羟基硬脂酸（12HSA unti）掺入聚l -乳酸（PLLA）中，得到软PLLA衍生物。l -乳酸与扁桃酸共聚得到玻璃化生物可降解共聚物，玻璃化转变温度高，可降解性提高。采用聚氧乙烯与l -丙交酯开环共聚的方法制备了更多的聚乳酸与聚氧乙烯嵌段共聚物，并将其分散到水中得到核壳纳米粒子。从这些颗粒中，通过螺旋PLLA块的结晶形成了特定的带结构。发现在混合聚类A-B-A三嵌段共聚物、pla - peg - plla和PDLA-PEG-PDLA分散体时发生了溶胶-凝胶转变。这种转变是由PLLA和PDLA链的立体络合作用驱动的。采用熔融纺丝法制备了以聚乙二醇酸（PGA）和聚乳酸（PLLA）为芯、为护套的芯-护套双组分纤维。该纤维比单一聚乳酸纤维具有更高的可降解性。利用产自洋葱假单胞菌的脂肪酶研究了聚丁二酸丁二酯（PBS）及其衍生物聚丁二酸丁二酯（PBST）的酶解过程。PBS和PBST分别通过酯链外切和内切进行生物降解。少