通过活生生的自由基聚合来调整纳米特征的化学和大小的多功能方法
Timothy A von Werne1, David S Germack, Erik C Hagberg
1IBM Almaden Research Center, Center for Polymeric Interfaces and Macromolecular Assemblies, 650 Harry Road, San Jose, California 95120-6099, USA.
Journal of the American Chemical Society
|March 27, 2003
概括
这项研究引入了一种新的方法,用于精确控制纳米尺寸特征大小和表面化学,使用接触成型和活体自由基聚合. 这种技术可以为先进材料提供可调节的特征尺寸和可适应的表面特性.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 纳米技术纳米技术
背景情况:
- 对纳米尺度特征尺寸和表面化学的精确控制对于先进的材料应用至关重要.
- 现有的纳米结构制造方法在调整尺寸和化学性质同时往往缺乏多功能性.
研究的目的:
- 开发一种新的方法来操纵纳米特征的大小和化学成分.
- 为了证明能够从单个主模式调整特征大小和表面特性的能力.
主要方法:
- 利用接触成型,在晶片上将一个交联光聚合物模拟成亚微米特征.
- 将含有启动子的单体纳入聚合物网络,用于功能组放大.
- 采用活生生的自由基聚合 (原子转移激素聚合和氧化物介导聚合) 来从有图案的地方生长聚合物刷.
主要成果:
- 成功复制了从5微米到60nm以下的特征.
- 增长的聚合物刷 (聚烯,聚甲基酸,聚二乙甲基酸) 具有控制的厚度 (10-143 nm) 和分子重量 (18,000-290,000 amu).
- 调整了从100nm到20nm的特征大小,并修改了表面化学,从水友性到疏水性.
结论:
- 接触成型和活体自由基聚合的结合方法为制造可调节的纳米特征提供了一个多功能平台.
- 这种方法可以精确控制纳米结构的物理尺寸和表面化学.
- 这种技术对需要精确设计的纳米级表面特性的应用具有潜力.
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