Control of association and gelation behavior of ABA triblock copolymers by means of conformational transition of B block

通过 B 嵌段的构象转变控制 ABA 三嵌段共聚物的缔合和凝胶行为

• 批准号: 15550105
• 负责人: INOMATA Katsuhiro
• 金额: $ 2.3万
• 依托单位: Nagoya Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2005
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-15550105/
• 关键词: water-soluble polypeptides; association behavior; gelation; helix-coil transition; light scattering; block copolymer; amphiphilic polymers; 架橋構造; トリブロック共重合体; ネットワーク構造; アミノリシス反応

Both-ends hydrophobically-modified water-soluble polypeptide, in which hydrophobic n-dodecyl (C12) groups are bonded at the both chain ends of poly[N^5-(2-hydroxyethyl) L-glutamine] (PHEG), has been prepared. Helix-coil transition and association behavior of this associative polypeptide in water/ethylene glycol (EG) mixed solvent, which is selective for PHEG block, have been investigated.1.In dilute aqueous solution, the middle PHEG chain is in random coil state, and isolated small-size micelles were formed by association of hydrophobic C12 groups. The micellar size increased drastically with the increase of EG content in the mixed solvent. These results suggest that the increase of the helix content of PHEG induces the increase of fraction of bridge conformation connecting different C12 associated cores, which results in the change of structure from an isolated associate to a large associate including multiple associated cores connected by PHEG chains.2.The above association scheme can explain process dependencies of sample preparation on the association in dilute solutions as well as gelation behavior of semi-concentrated solutions.3.Association behavior of one-end hydrophobically-modified PHEGs was also investigated. Association strength was increased with the increase of hydrophobicity of the terminal alkyl chain. Conformational transition of PHEG chain induced a change in micellar structure, i.e., spherical shape when PHEG is in random coil state and worm-like cylinder when PHEG in α-helix conformation.4.Block copolymer of PHEG and poly(ethylene glycol) was prepared, and its association in a selective solvent for poly(ethylene glycol) was investigated. When PHEG is in α-helical state, the associate is in hollow cylindrical shape because of a packing of rigid PHEG chain. When PHEG prefer to take random-coil conformation, formation of a normal core-corona type wormlike cylinder was suggested.

制备了双末端疏水改性的水溶性多肽，其中疏水性的正十二烷基（C12）基团键合在聚[N ^-5-（2-羟乙基）L-谷氨酰胺]（PHEG）的两个链末端。研究了该缔合多肽在水/乙二醇（EG）混合溶剂中的螺旋-卷曲转变和缔合行为. 1.在稀水溶液中，中间的PHEG链处于无规卷曲状态，疏水的C12基团缔合形成孤立的小尺寸胶束.随着混合溶剂中EG含量的增加，胶束尺寸急剧增大。这些结果表明，PHEG的螺旋含量的增加导致连接不同C12缔合核心的桥构象分数的增加，2.上述缔合机理可以解释样品制备过程对稀溶液中缔合作用的依赖性，半浓溶液的凝胶化行为。3.研究了单端疏水改性PHEGs的缔合行为。缔合强度随着末端烷基链疏水性的增加而增加。PHEG链的构象转变引起胶束结构的变化，即，4.制备了PHEG与聚乙二醇的嵌段共聚物，并研究了其在聚乙二醇选择性溶剂中的缔合作用。当PHEG处于α-螺旋状态时，由于刚性PHEG链的堆积，缔合物呈空心圆柱状。当PHEG倾向于无规卷曲构象时，则形成了正常的核冠型蠕虫状圆柱体。

项目成果

Akinori Takasu: "Threo-Disyndiotactic Polymerization of (E,E)-Alkyl Sorbates Catalyzed by Bulky Organo-aluminum Lewis Acid via "Alternating Turning Over Polymerization (ATOP)" Mechanism"Macromolecules. 36・19. 7055-7064 (2003)

Akinori Takasu：“通过“交替翻转聚合（ATOP）”机制，大体积有机铝路易斯酸催化的（E，E）-烷基山梨酸酯的三元双立构聚合”36・19（2003）。

Side-chain Crystallization Behavior of Graft Copolymers Consisting of Amorphous Main Chain and Crystalline Side Chains

非晶主链与结晶侧链接枝共聚物的侧链结晶行为

• 发表时间: 2005
• 期刊: Journal of Polymer Science, Part B, Polymer Physics 43・1
• 作者: Katsuhiro Inomata;Katsuhiro Inomata;Katsuhiro Inomata;Katsuhiro Inomata;Katsuhiro Inomata;Katsuhiro Inomata;Katsuhiro Inomata;Katsuhiro Inomata;Katsuhiro Inomata
• 通讯作者: Katsuhiro Inomata

Structural study on rodlike aromatic polyimides derived by solid-state thermal and chemical imidization of poly(amic n-dodecyl ester)

• DOI: 10.1016/j.molstruc.2004.04.033
• 发表时间: 2005-04
• 期刊: Journal of Molecular Structure
• 影响因子: 3.8
• 作者: K. Inomata;Y. Ozeki;Sachio Shimomura;Y. Sakamoto;E. Nakanishi

猪股克弘: "非晶性主鎖と結晶性側鎖からなるグラフト共重合体の相挙動と高次構造"高分子加工. 53・3. 134-139 (2004)

Katsuhiro Inomata：“由非晶主链和结晶侧链组成的接枝共聚物的相行为和高阶结构” 53・3（2004）。

Helix-Coil Transition and Micellar Structure of Poly(ethylene glycol)-block-poly[N^5-(2-hydroxyethyl) L-glutamine] in Cyclohexanol/Water Mixed Solvents

环己醇/水混合溶剂中聚乙二醇-嵌段-聚[N^5-(2-羟乙基)L-谷氨酰胺]的螺旋-螺旋转变和胶束结构

• 发表时间: 2005
• 期刊: Polym.J. 37(6)
• 作者: Katsuhiro Inomata;Katsuhiro Inomata;Katsuhiro Inomata;Katsuhiro Inomata;Katsuhiro Inomata;Katsuhiro Inomata
• 通讯作者: Katsuhiro Inomata