摘要/Abstract
研究了包含聚肽嵌段的两亲共聚物聚乙二醇-b-聚(L-谷氨酸)(PEG-b-PGlu)与4-甲基-4-氮杂[4]螺烯鎓离子(Me[4]H)的电荷复合自组装行为, 讨论了聚肽链段长度、谷氨酸单元与螺烯物质的量比、pH值等因素对组装体形貌的影响. 研究发现, 当刚-柔型嵌段聚合物与刚性、大尺寸并具有诱导作用的小分子共同组装时, 遵循与柔性大分子电荷复合组装完全不同的规律. PEG-b-PGlu/Me[4]H的电荷复合组装体形貌由π-π堆叠作用、两亲嵌段聚肽的亲疏水比、PGlu链段的刚硬程度共同决定, 这些作用在组装过程中相互制约, 当π-π堆叠作用占主导地位时, 得到以指针状和条带状等平面结构为主的组装形貌.
关键词: 电荷复合自组装, 两亲嵌段共聚物, 螺烯
Amphiphilic block copolypeptides of polyethylene glycol-b-poly(L-glutamic acid) (PEG-b-PGlu) were synthesized to self-assemble with 4-methyl-4-aza[4]helicene onium ion (Me[4]H) in water through charge-conjugation. The morphology of the assemblies was studied by varying PGlu block length, the molar ratio of Glu unit/Me[4]H and pH value. It was found that when rigid-flexible block copolymers were assembled together with small molecules which had rigid, large size and inductive effect, they would follow a completely different law from the charge-conjugated assembly of flexible macromolecules. The self-assemblies were controlled by the π-π stacking of helicene, together with the volume fraction of the hydrophobic parts and the rigidity of PGlu segments. These effects restricted each other in the assembly process. When π-π stacking was dominant, assembly morphologies with pointer-like and strip-like planar structures were obtained.
Key words: charge-conjugated self-assembly, amphiphilic block copolymer, helicene
PDF全文下载地址:
点我下载PDF
