Self-Assembly of Doublets from Flattened Polymer Colloids

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• 作者：Laura Mely Ram铆rez ; Adrian S. Smith ; Deniz B. Unal ; Ralph H. Colby ; Darrell Velegol
• 刊名：Langmuir
• 出版年：2012
• 出版时间：March 6, 2012
• 年：2012
• 卷：28
• 期：9
• 页码：4086-4094
• 全文大小：467K
• 年卷期：v.28,no.9(March 6, 2012)
• ISSN：1520-5827

文摘

Bottom-up fabrication methods are used to assemble strong yet flexible colloidal doublets. Part of a spherical particle is flattened, increasing the effective interaction area with another particle having a flat region. In the presence of a moderate ionic strength, the flat region on one particle will preferentially 鈥渂ond鈥?to a flat region on another particle in a deep (鈮?0 kT) secondary energy minimum. No external field is applied during the assembly process. Under the right conditions, the flat鈥揻lat bonding strength is 鈮?0脳 that of a sphere鈥搒phere interaction. Not only can flat鈥揻lat bonds be quite strong, but they are expected to remain freely rotatable and flexible, with negligible energy barriers for rotation because particles reside in a deep secondary energy minimum with a 20鈥?0 nm layer of fluid between the 1 渭m radius particles. We present a controlled technique to flatten the particles at room temperature, the modeling of the interparticle forces for flattened spheres, and the experimental data for the self-assembly of flat鈥揻lat doublets.