Surface priming and the self-assembly of hydrogen-bonded multilayer capsules and films
Surface priming and the self-assembly of hydrogen-bonded multilayer capsules and films
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DOI：
10.1021/ma0501895
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发表时间：
2005-05-31
期刊：
影响因子：
5.5
通讯作者：
Sukhishvili, SA
中科院分区：
文献类型：
--
作者：
Kozlovskaya, V;Yakovlev, S;Sukhishvili, SA
我们系统地研究了氢键多层膜的生长如何受到衬底形状和电荷以及聚阳离子前体层沉积条件的影响。我们对比强烈结合的聚（N-乙烯基吡咯烷酮）/聚（甲基丙烯酸）（PVPON/PMAA）和弱结合的聚（环氧乙烷））/聚（甲基丙烯酸）（PEO/PMAA）系统的生长时，这些多层膜沉积到裸或聚（乙烯亚胺）（PEI）处理表面的CdCO 3晶体，胶体二氧化硅颗粒，或硅片。与平坦基材相比，当胶体颗粒用作基材时，氢键多层膜的生长被显著抑制，这可能是由于在聚合物吸附期间通过摇动颗粒基材来增强链去除。虽然在PVPON/PMAA系统中，无论前体层的吸附历史如何，在经吸附剂处理的基底上都发生了稳健的多层沉积，但PEO/PAMA膜的生长严重依赖于PEI吸附的条件。PEO/PMAA薄膜可以生长在CdCO 3基板上时，PEI前体被允许吸附在一个pH值高于用于氢键沉积，但PEO/PMAA薄膜生长被抑制时，PEI沉积在相同的pH值用于薄膜沉积。我们合理化这种效果的前体层的氢键多层膜的生长中发挥的作用，我们证实了我们的假设，通过监测电泳迁移率，电离，和前体层内沉积的聚合物的量。最后，我们提出了两种方法来促进氢键多层膜的生长到基板上进行不利的高负电荷：建设的混合氢键多层膜和使用二价阳离子作为促进剂的PMAA结合。
We present a systematic study of how growth of hydrogen-bonded multilayers is affected by the substrate shape and charge as well as by the deposition conditions of a polycation precursor layer. We contrast growth of strongly bound poly(N-vinylpyrrolidone)/poly(methacrylic acid) (PVPON/PMAA) and weakly bound poly(ethylene oxide))/poly(methacrylic acid) (PEO/PMAA) systems when these multilayers are deposited onto bare or poly(ethylene imine) (PEI)-treated surfaces of CdCO3 crystals, colloidal silica particles, or silicon wafers. As compared to flat substrates, growth of hydrogen-bonded multilayers was significantly inhibited when colloidal particles were used as a substrate, presumably due to the enhanced chain removal by shaking the particulate substrate during the polymer adsorption. While in the PVPON/PMAA system robust multilayer deposition occurred on the precursor-treated substrate regardless of the adsorption history of the precursor layer, growth of PEO/PAMA films was critically dependent on the conditions of PEI adsorption. PEO/PMAA films could be grown on CdCO3 substrates when the PEI precursor was allowed to adsorb at a pH value higher than that used for hydrogen-bonding deposition, but PEO/PMAA film growth was inhibited when PEI was deposited at the same pH used for film deposition. We rationalize this effect in terms of the role the precursor layer plays on the growth of hydrogen-bonded multilayers, and we confirm our hypothesis by monitoring electrophoretic mobility, ionization, and the amount of polymer deposited within the precursor layer. Finally, we suggest two ways to facilitate growth of hydrogen-bonded multilayers onto substrates which carry unfavorably high negative charge: construction of hybrid hydrogen-bonded multilayers and the use of divalent cations as promoters of PMAA binding.