聚(L-丙氨酸-co-羟丙-L-谷氨酰胺)无规共聚物的两亲性及其胶束行为研究

AMPHIPHILICITY AND MICELLIZATION OF POLY(L-ALANINE-co-5,N-HYDROXYPROPYL-L-GLUTAMINE)

采用丙氨酸作为疏水聚合单体,谷氨酸作为亲水聚合单体,一步开环聚合反应,合成了具有两亲性的聚氨基酸无规共聚物.利用IR,1H-NMR等方法对所合成的聚合物进行了详细的表征,结果表明两种单体都能够按照投料比参加聚合反应生成无规共聚物.对比聚丙氨酸-聚羟丙谷氨酰胺嵌段共聚物,探讨了无规共聚物与嵌段共聚物在两亲性及结构性质上的差异和特点.研究表明,聚(L-丙氨酸-co-羟丙-L-谷氨酰胺)无规共聚物与嵌段共聚物一样,具有两亲性,在水溶液中也能够形成胶束,但胶束尺寸较嵌段共聚物要小,胶束形态也不像嵌段共聚物是规整的球形.实验发现,亲疏水单体的比例对胶束的形成有很大影响,P(A10-co-HPG40)所制得的胶束分散最为均匀.所形成的胶束以疏水的聚丙氨酸为内核,亲水的聚羟丙谷氨酰胺为外壳.

Aminolysis was used to improve the hydrophilicity of poly（ γ-benzyl-L-glutamate）, PBLG. Hydrophobie benzyl side chain groups in PBLG were changed to hydrophilie hydroxyalkyl groups by aminolysis reaction. Poly（ L- alanine- co- 5, N- hydroxypropyl- L- glutamine）, （ P （ A- co- HPG） ） and poly （ L- alanine） - b - poly （ 5, N - hydroxypropyl- L- glutamine）, （PA-b-PHPG） were synthesized in this paper, both initiated by n-propylamine. The structure and basic properties were characterized by IR and 1H-NMR. Both PA-b-PHPG and P（A-co-HPG） have the amphiphilic properties, where PA is the hydrophobic part and PHPG is the hydrophilic part. Compared with the block copolymer, the synthesis of random eopolymer P（A-co-HPG） was more simple and of high efficiency. At the same time, the mieellization processes of PA10-b-PHPG40 and P（A10-co-HPG40） were monitored by 1H-NMR. TEM results showed that both PA10-b-PHPG40 and P（A10-co-HPG40 ） could self-assembled into evenly mieelles in water. However, the size of the micelles made of random copolymers was smaller than that of block eopolymers, and the shape of random eopolymer mieelles were not regular spheres as rnicelles made of block copolymer. At the same time, it was found that the ratio between hydrophiphilic and hydrophobic monomers played a very important role in micelle formation. The most uniform mieelle size distribution was observed in P（A10-CO-HPG40 ） rnicellar solutions.