当前位置: X-MOL 学术Macromolecules › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Tuning of Folding Height in Bilayer-Folded Lamellae by Bending Rigidity Control
Macromolecules ( IF 5.1 ) Pub Date : 2024-08-29 , DOI: 10.1021/acs.macromol.4c00298
Minjoong Shin 1 , Soon Mo Park 2, 3 , Jimin Yoo 1 , Ahjin Lee 1 , Hyungju Ahn 4 , Dong Ki Yoon 1, 2, 5 , Myungeun Seo 1, 5
Affiliation  

We investigated the bilayer-folded lamellar (Lf) mesophase appearing in the aqueous solution of amphiphilic random copolymers. A series of copolymers were synthesized by reversible addition–fragmentation chain transfer copolymerization of oligo(ethylene glycol) acrylate with alkyl acrylate with different alkyl chain lengths from octyl (C8) to octadecyl (C18). The alkyl acrylate composition was adjusted between 50–60 mol %. In the concentrated solution with the carbon number of the alkyl side chain higher than 10, the copolymers associated in water via hydrophobic interaction between the alkyl chains to produce micellar bilayers, which were periodically folded into bilayer-folded lamellae. The appearance of a small-angle X-ray scattering (SAXS) peak at a low scattering vector corresponding to >10 nm length scale clearly distinguished the bilayer-folded lamellae from the micellar lamellae with the domain spacing of 5–7 nm. Two-dimensional (2D) SAXS corroborated the presence of bilayer-folded lamellae developing perpendicularly to the micellar lamellae, which is consistent with our previous report. While the Lf phase was observed at room temperature for dodecyl (C12) and tetradecyl (C14) side chains that formed amorphous packing, crystalline hexadecyl (C16) and octadecyl (C18) chains seem to disturb bilayer folding. Heating the solution above the melting temperature of the alkyl chains produced the Lf phase with the largest folding height in the case of C16. The scaling relationship of the folding height to the carbon number supports the idea that the bending rigidity of the bilayer influences the length scale of folding.

中文翻译:


通过弯曲刚度控制调节双层折叠薄片的折叠高度



我们研究了两亲性无规共聚物水溶液中出现的双层折叠层状( L f )中间相。通过低聚(乙二醇)丙烯酸酯与具有从辛基(C8)到十八烷基(C18)不同烷基链长度的丙烯酸烷基酯的可逆加成-断裂链转移共聚合成了一系列共聚物。丙烯酸烷基酯的组成调整在50-60 mol%之间。在烷基侧链碳数大于10的浓溶液中,共聚物通过烷基链之间的疏水相互作用在水中缔合,产生胶束双层,并周期性折叠成双层折叠片层。在对应于 >10 nm 长度尺度的低散射矢量处出现小角 X 射线散射 (SAXS) 峰,可以清楚地区分双层折叠片层与域间距为 5-7 nm 的胶束片层。二维 (2D) SAXS 证实了垂直于胶束片层发育的双层折叠片层的存在,这与我们之前的报告一致。虽然在室温下观察到形成无定形堆积的十二烷基 (C12) 和十四烷基 (C14) 侧链的L f相,但结晶十六烷基 (C16) 和十八烷基 (C18) 链似乎会干扰双层折叠。将溶液加热到烷基链的熔化温度以上,产生了在 C16 的情况下具有最大折叠高度的L f相。折叠高度与碳数的比例关系支持双层的弯曲刚度影响折叠长度尺度的观点。
更新日期:2024-08-29
down
wechat
bug