在選擇性溶劑中具有二嵌段側鏈Am(-graft-B3Ay)n的接枝共聚物在先前已經被研究探討，可自組裝成囊泡，但預計其結構與脂質雙層有明顯不同。令人驚訝的是，在相同的共聚物濃度下，囊泡中交替的疏水性A-嵌段和親水性B-嵌段層的數量可以從單層到多層（例如七層）變化。共聚物層的面積密度在整個膜上是不均勻的。不同層之間的這種結構差異歸因於相鄰環境和層的曲率。由於不尋常的聚合物構形，聚合物體的微觀結構比脂質體複雜得多。事實上，共聚物可以貢獻一個或兩個親水層，它可以參與多達三個疏水層。還研究了主鏈長度(m)和側鏈長度(y)以及滲透動力學的影響。發現疏水層的厚度隨著側鏈長度的增加而增加，但對主鏈長度不敏感。雖然滲透時間隨著平面膜的層數而增長，但由於拉普拉斯壓力，導致球形囊泡的行為相反。

Graft copolymers with diblock side-chains Am(-graft-B3Ay)n in selective solvent have been reported to self-assemble into vesicles, but the structure is expected to differ distinctly from lipid bilayers. Surprisingly, the number of the alternating hydrophobic A-block and hydrophilic B-block layers in the vesicle can vary from monolayer to multilayer such as hepta-layer, subject to the same copolymer concentration. The area density of the copolymer layer is not uniform across the membrane. This structural difference among different layers is attributed to the neighboring environment and the curvature of the layer. Because of unusual polymer conformations, the microscopic structure of polymersome is much more intricate than that of liposome. In fact, a copolymer can contribute to a single or two hydrophilic layers and it can participate up to three hydrophobic layers. The influences of the backbone length (m) and side-chain length (y) and the permeation dynamics are also studied. The thickness of hydrophobic layers is found to rise with increasing the side-chain length but not sensitive to the backbone length. Although the permeation time grows with the layer number for planar membranes, the opposite behavior is observed for spherical vesicles owing to Laplace pressure.

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