A-块-B-随机-C) 聚合物在表面上具有相同的块表面能量,并与B-随机-C聚合物功能化
Hongbo Feng1, Benjamin Kash1, Soonmin Yim1
1Pritzker School of Molecular Engineering, University of Chicago, 5640 S. Ellis Avenue, Chicago, Illinois 60637, United States.
Langmuir : the ACS journal of surfaces and colloids
|October 2, 2023
概括
控制块共聚合物 (BCP) 域定向是纳米模式的关键. 这项研究表明,通过特定的硫醇化学物质调整表面能量如何影响BCP湿行为和基板上的域对齐.
科学领域:
- 聚合物科学 聚合物科学
- 材料科学 材料科学 材料科学
- 表面化学 表面化学
背景情况:
- 自组装区块共聚物 (BCP) 对于创建纳米模式至关重要.
- 在BCP薄膜中实现垂直域定向对于应用是可取的.
- 域定向取决于BCP域,基板和自由表面之间的界面相互作用.
研究的目的:
- 为了研究不同界面相互作用如何影响块共聚合物湿行为.
- 用量身定制的纳米涂层来证明在A-block-(B-random-C) BCP中对域定向的控制.
- 为了将表面能量修改与BCP域对齐相关联.
主要方法:
- 合成的A-块-(B-随机-C) 块共聚合物使用醇-环氧点击化学与特定的功能化醇 (三乙乙醇,2-mercaptopyridine,甲基糖).
- 使用相应的B-随机-C共聚合物制造的基板纳米涂层.
- 通过扫描电子显微镜,确定表面能量等 (Δγair = 0) 和与基质的界面能量等 (Δγsub = 0) 的组成比.
- 分析了基于界面能量和弗洛里-哈金斯相互作用参数 (χ) 的湿行为.
主要成果:
- 根据BCP功能化中使用的特定醇对观察到两种不同的湿行为.
- 在平衡表面能量 (Δγair = 0) 和平衡基质界面能量 (Δγsub = 0) 所需的组成比率之间,在两种醇对之间发现了显著的差异.
- 对于甲基硫糖酸盐和三乙乙醇对,确定了两个不同的组成窗口来实现Dγsub = 0,由热力学相互作用和BCP架构解释.
结论:
- 醇化学的选择显著影响到所需的条件,以实现所需的湿化行为和BCP中的域定向.
- 用特定的随机共聚物量身定制基板纳米涂层,可以控制BCP自组装.
- 了解界面能量,热力学相互作用和BCP架构之间的相互作用对于设计纳米模式策略至关重要.
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