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首页> 外文期刊>Journal of Applied Polymer Science >Atomic force microscopy studies of admicellar polymerization polystyrene-modified amorphous silica
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Atomic force microscopy studies of admicellar polymerization polystyrene-modified amorphous silica

机译：原子聚合的聚苯乙烯改性无定形二氧化硅的原子力显微镜研究

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Atomic force microscopy was used to study polystyrene-modified silica surfaces produced by admicellar polymerization (polymerization of monomers solubilized in adsorbed surfactant aggregates). The goal was to examine changes in the location and nature of the formed polystyrene resulting from changes in the surfactant and monomer feed levels on precipitated silica. Normal tapping and phase-contrast modes in air were used to image the topography of the polystyrene-modified silica. Moderate-to-light force-tapping mode was used to differentiate between the silica surface and adsorbed water or polymer. The formed polystyrene exists primarily in the pores, with patches extending onto the exposed surface of the silica particles. At moderate tapping forces, darker phase regions were observed in the valleys and pores of the silica in both the modified and the unmodified samples. Upon higher magnification, the darker regions disappear on unmodified silicas, whereas polymer bands become evident on the modified silicas. At lower loadings of surfactant and monomer, the number and extent of polymer patches decreased, with polymer being found only in pores. The polystyrene patches observed inside the valleys of the amorphous silica varied from 1 to 10 nm in thickness. The structure of the polystyrene film formed on precipitated silica was found to be insensitive to the surfactant feed concentration. (C) 2002 Wiley Periodicals, Inc. [References: 35]
机译：原子力显微镜用于研究通过原子聚合（溶解在吸附的表面活性剂聚集体中的单体的聚合反应）产生的聚苯乙烯改性的二氧化硅表面。目的是检查由沉淀二氧化硅上表面活性剂和单体进料量的变化引起的形成的聚苯乙烯的位置和性质的变化。空气中的常规拍打和相衬模式用于对聚苯乙烯改性二氧化硅的形貌进行成像。使用轻度轻敲模式来区分二氧化硅表面和吸附的水或聚合物。形成的聚苯乙烯主要存在于孔中，斑块延伸到二氧化硅颗粒的暴露表面。在中等的攻丝力下，在改性和未改性样品中，在硅谷和孔中都观察到较暗的相区域。在较高的放大倍数下，较暗的区域在未改性的二氧化硅上消失，而聚合物带在改性的二氧化硅上变得明显。在较低的表面活性剂和单体负载量下，聚合物斑块的数量和范围减少，仅在孔中发现聚合物。在无定形硅谷内部观察到的聚苯乙烯贴片的厚度在1至10 nm之间变化。发现在沉淀的二氧化硅上形成的聚苯乙烯膜的结构对表面活性剂进料浓度不敏感。 （C）2002 Wiley Periodicals，Inc. [参考：35]

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