Drying dissipative structures of cationic gel spheres of lightly cross-linked poly(2-vinyl pyridine) (170??180?nm in diameter) in the deionized aqueous suspension

详细信息    查看全文

• 作者：Tsuneo Okubo (1)
  Syuji Fujii (2)
  Yoshinobu Nakamura (2)
  
• 关键词：Cationic gel spheres ; Poly(2 ; vinyl pyridine) ; Drying pattern ; Dissipative structure ; Ordered array ; Similar ; sized aggregates ; Convectional pattern
• 刊名：Colloid & Polymer Science
• 出版年：2013
• 出版时间：December 2013
• 年：2013
• 卷：291
• 期：12
• 页码：2805-2813
• 全文大小：
• 作者单位：Tsuneo Okubo (1)
  Syuji Fujii (2)
  Yoshinobu Nakamura (2)
  
  1. Institute for Colloidal Organization, Hatoyama 3-1-112, Uji, Kyoto, 611-0012, Japan
  2. Department of Applied Chemistry, Faculty of Engineering, Osaka Institute of Technology, 5-16-1, Ohmiya, Asahi-ku, Osaka, 535-8585, Japan
  
• ISSN：1435-1536

文摘

Drying dissipative patterns of cationic gel crystals of lightly cross-linked poly(2-vinyl pyridine) spheres (AIBA-P2VP, 170??180 nm in diameter) were observed on a cover glass, a watch glass, and a Petri glass dish. Convectional patterns were recognized with the naked eyes. Two kinds of the broad rings were observed at the outside edge and inner region in the macroscopic drying pattern, and their size at the inner regions first decreased and then turned to increase as gel concentration decreased. Formation of the similar-sized aggregates, i.e., hierarchical aggregation and their ordered arrays were observed. This work supported strongly the formation of the microscopic drying structures of (a) ordered rings, (b) flickering ordered spoke-lines, (c) net structure, and (d) lattice-like ordered structures of the aggregated particles. The ordering of the similar-sized aggregates of the cationic gel spheres (AIBA-P2VP) in this work is similar to that of the large cationic gel spheres of poly(2-vinyl pyridine) (385??400?nm in diameter) and further to that of the anionic thermosensitive gel spheres of poly(N-isopropyl acrylamide). Role of the electrical double layers around the aggregates and their interaction with the substrates during dryness are important for the ordering. The microscopic drying patterns of gel spheres were different from those of linear-type polymers and also from typical colloidal hard spheres, though the macroscopic patterns such as broad ring formation were similar to each other.