Surface-Initiated Reversible Addition鈥揊ragmentation Chain Transfer (RAFT) Polymerization from Fine Particles Functionalized with Trithiocarbonates

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• 作者：Kohji Ohno ; Ying Ma ; Yun Huang ; Chizuru Mori ; Yoshikazu Yahata ; Yoshinobu Tsujii ; Thomas Maschmeyer ; John Moraes ; S茅bastien Perrier
• 刊名：Macromolecules
• 出版年：2011
• 出版时间：November 22, 2011
• 年：2011
• 卷：44
• 期：22
• 页码：8944-8953
• 全文大小：975K
• 年卷期：v.44,no.22(November 22, 2011)
• ISSN：1520-5835

文摘

Monodisperse silica particles (SiPs) were surface-modified with a newly designed reversible addition鈥揻ragmentation chain transfer (RAFT) agent having a triethoxysilane moiety, 6-(triethoxysilyl) 2-(((methylthio)carbonothioyl)thio)-2-phenylacetate (EHT). Surface-initiated RAFT polymerization of styrene was carried out with the EHT-modified SiPs in the presence of a free RAFT agent. The polymerization proceeded in a living manner, producing SiPs coated with well-defined polystyrene of a target molecular weight with a graft density as high as 0.3 chains/nm². Similarly, polymerizations of methyl methacrylate (MMA), N-isopropylacrylamide, and n-butyl acrylate were conducted, providing SiPs grafted with concentrated (high-density) polymer brushes. In all examined cases, the hybrid particles were highly dispersible in solvents for graft polymers, without causing any aggregations. Owing to exceptionally high uniformity and perfect dispersibility, these hybrid particles formed two- and three-dimensionally ordered arrays at the air鈥搘ater interface and in suspension, respectively. In addition to the surface-grafting on SiPs, the versatility of this technique was demonstrated by carrying out surface-initiated RAFT polymerization of styrene from iron oxide nanoparticles modified with EHT.