Effect of block sequence and block length on the stimuli-responsive behavior of polyampholyte brushes: hydrogen bonding and electrostatic interaction as the driving force for surface rearrangement
Effect of block sequence and block length on the stimuli-responsive behavior of polyampholyte brushes: hydrogen bonding and electrostatic interaction as the driving force for surface rearrangement
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嵌段序列和嵌段长度对聚两性电解质刷刺激响应行为的影响：氢键和静电相互作用作为表面重排的驱动力
DOI：
10.1039/b805611k
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发表时间：
2009-02
期刊：
影响因子：
3.4
通讯作者：
Han, Yanchun
中科院分区：
文献类型：
--
作者：
Yu, Kai;Han, Yanchun
通过连续表面引发原子转移自由基聚合（ATRP）合成了具有不同嵌段序列（Si/SiO2/聚（丙烯酸）-b-聚（2-乙烯基吡啶）（PAA-b-P2VP）刷和Si/SiO2/P2VP-b-PAA刷）和不同嵌段长度的二嵌段聚两性电解质刷。 PAA嵌段是通过相应的聚(丙烯酸叔丁酯)水解获得的。聚两性电解质刷表现出独特的 pH 响应行为。在中间 pH 范围内，由于相反电荷块之间的静电相互作用形成聚电解质复合物，刷子表现出较低的亲水润湿行为和较粗糙的表面形态。在低pH和高pH区域，聚两性电解质刷的重排表现出对嵌段序列和嵌段长度的极大依赖性。具有P2VP-b-PAA序列的聚两性电解质刷在酸性水溶液（低pH值）和碱性水溶液（高pH值）交替处理过程中发生重排。具有PAA-b-P2VP序列的刷子没有表现出明显的重排。然而，随着 PAA-b-P2VP 刷内部 PAA 嵌段长度的增加，嵌段之间的氢键相互作用变得足够强，足以实现表面重排，并最终将内部 PAA 嵌段定位在低 pH 区域的聚合物-空气界面处。在高pH值区域，聚合物刷表面重排的机会最小。尽管内部块很长，但 P2VP 块更集中在界面处。
Diblock polyampholyte brushes with different block sequences (Si/SiO2/poly(acrylic acid)-b-poly(2-vinylpyridine) (PAA-b-P2VP) brushes and Si/SiO2/P2VP-b-PAA brushes) and different block lengths were synthesized by sequent surface-initiated atom transfer radical polymerization (ATRP). The PAA block was obtained through hydrolysis from the corresponding poly(tert-butyl acrylate). The polyampholyte brushes demonstrated unique pH-responsive behavior. In the intermediate pH region, the brushes exhibited a less hydrophilic wetting behavior and a rougher surface morphology due to the formation of polyelectrolyte complex through electrostatic interaction between oppositely charged blocks. In the low pH and high pH regions, the rearrangement of polyampholyte brushes showed great dependence on the block sequence and block length. The polyampholyte brushes with P2VP-b-PAA sequence underwent rearrangement during alternative treatment by acidic aqueous solution (low pH value) and basic aqueous solution (high pH value). The brushes with PAA-b-P2VP sequence did not show obvious rearrangement. Nevertheless, with increasing the length of inner PAA block for PAA-b-P2VP brushes, the hydrogen-bonding interaction between blocks became strong enough to implement surface rearrangement and eventually localized the inner PAA block at the polymer–air interface in the low pH region. In the high pH region, polymer brushes had least chance of surface rearrangement. P2VP block was more localized at the interface despite of the length of inner block.
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DOI：
10.1007/s101890170016
发表时间：
2001-10
期刊：
The European Physical Journal E
影响因子：
--
作者：
N. Shusharina;P. Linse
通讯作者：
N. Shusharina;P. Linse
影响因子：
5.5
作者：
Bin Zhao;W. Brittain;Wensheng Zhou;Stephen Z. D. Cheng
通讯作者：
Bin Zhao;W. Brittain;Wensheng Zhou;Stephen Z. D. Cheng
影响因子：
5.5
作者：
Amit Y. Sankhe;S. Husson;S. Kilbey
通讯作者：
Amit Y. Sankhe;S. Husson;S. Kilbey
影响因子：
5.5
作者：
Heidi R. Motzer;P. Painter;M. Coleman
通讯作者：
Heidi R. Motzer;P. Painter;M. Coleman
影响因子：
5.5
作者：
Matyjaszewski, K;Miller, PJ;Pakula, T
通讯作者：
Pakula, T