Is Osmotic Pressure Relevant in the Mechanical Confinement of a Polymer Brush?
Is Osmotic Pressure Relevant in the Mechanical Confinement of a Polymer Brush?
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DOI：
10.1021/ma502246r
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发表时间：
2015-04-14
期刊：
影响因子：
5.5
通讯作者：
Prescott, Stuart W.
中科院分区：
文献类型：
--
作者：
Abbott, Stephen B.;de Vos, Wiebe M.;Prescott, Stuart W.
用中子反射率和表面力式仪器相结合的方法测量了聚合物电刷在约束条件下的结构。这些样品要么是聚环氧乙烷(PEO)，用于研究接枝密度的影响，要么是聚丙烯酸(PAA)，用于确定限制条件下电荷对聚合物刷子结构的影响。在没有限制的情况下，PEO和PAA刷子都被发现高度膨胀的水，>；50%v/v，与预期的抛物线刷子结构。实验发现，压缩PEO刷子只需0.5bar的限制就可以将刷子减少到密度均匀的聚合物块，该聚合物块显著脱水，
The structures of polymer brushes under confinement were measured using a combination of neutron reflectivity and a surface force type apparatus. The samples were either poly(ethylene oxide), PEO, used to investigate the effect of the grafting density or poly(acrylic acid), PAA, used to determine the effect of charge on the structure of a polymer brushes under confinement. Without confinement both PEO and PAA brushes are found to be highly swollen with water, >50% v/v, with the expected parabolic brush structure. Compression of the PEO brushes with as little as 0.5 bar of confinement is found experimentally to reduce the brush to a polymer block of uniform density that is significantly dehydrated,