Drying Mechanism of Poly(N-isopropylacrylamide) Microgel Dispersions
Drying Mechanism of Poly(N-isopropylacrylamide) Microgel Dispersions
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DOI：
10.1021/la302465w
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发表时间：
2012-09-11
期刊：
影响因子：
3.9
通讯作者：
Suzuki, Daisuke
中科院分区：
文献类型：
--
作者：
Horigome, Koji;Suzuki, Daisuke
研究了聚N-异丙基丙烯酰胺(PNIPAM)微凝胶分散体的干燥机理。以N-异丙基丙烯酰胺、N，N‘-亚甲基双丙烯酰胺和水溶性引发剂为引发剂，采用程序升温自由基聚合法合成了微凝胶。用数码相机和光学显微镜观察微凝胶分散体的干燥过程，并用扫描电子显微镜观察干燥后的结构。我们发现微凝胶的存在改变了水的干燥过程的行为。特别是，微凝胶在几分钟内被选择性地吸附在空气/水界面上，而与微凝胶浓度无关。通过改变分散体的微凝胶浓度，阐明了微凝胶薄膜的干燥机理与结构之间的关系。
The drying mechanism of poly(N-isopropylacrylamide) (pNIPAm) microgel dispersions was investigated. The microgels were synthesized by temperature-programmed aqueous free radical precipitation polymerization using NIPAm, N,N'-methylenebis(acrylamide), and water-soluble initiator. Drying processes of the microgel dispersions were observed with a digital camera and an optical microscope, and the resultant dried structures were observed by scanning electron microscopy. We found that the presence of the microgels changed the behavior of the drying process of water. In particular, the microgels were adsorbed at the air/water interface selectively within a few minutes irrespective of the microgel concentration. The relationship between the drying mechanism and structure of the resultant microgel thin film has been clarified by changing the microgel concentration of the dispersions.