Preparation and applications of fluoroalkyl end-capped vinyltrimethoxysilane oligomeric silica/magnetite composites Hideo Sawada , Seigo Okada, Katsumi Yamashita Department of Frontier Materials Chemistry, Graduate School of Science and Technology, Hirosaki University, Hirosaki 036-8561, Japan *email: hideosaw@hirosaki-u.ac.jp It is well known that ABA triblock-type two fluoroalkyl end-capped oligomers [R F -(M) n -R F ; R F = fluoroalkyl groups; M = radical polymerizable hydrocarbon monomers] can be synthesized by using fluoroalkanoyl peroxide as a key intermediate to form the nanometer size-controlled self-assembled molecular aggregates through the aggregation of terminal fluoroalkyl segments in aqueous and organic media [1, 2]. The fluorinated oligomeric aggregates can interact with a variety of inorganic guest molecules such as silica nanoparticles to afford the colloidal stable fluorinated oligomeric aggregates/guest molecule nanocomposites [2, 3]. Thus, it is of particular interest to develop the colloidal stable magnetite nanoparticles by using two fluoroalkyl end-capped oligomers. Here we report that fluoroalkyl end-capped vinyltrimethoxysilaneoligomeric silica/magnetite composites [R F -(VM-SiO 3/2 ) n -R F / Mag ] can be prepared by the sol-gelreaction of the corresponding fluorinatedoligomer [R F -(CH 2 CHSi(OMe) 3 ) n -R F ; R F =CF(CF 3 )OC 3 F 7 : R F -(VM) n −R F ] in the presence of magnetite (Fe 3 O 4 : Mag ) nanoparticles. The R F -(VM- SiO 3/2 ) n -R F / Mag composite powders thus obtained were applied to the surface modification of glass to exhibit a superoleophilic/superhydrophobic characteristic on the modified surface. These fluorinated composite powders are also well spread over water interface, not precipitated into water. Interestingly, it was demonstrated that these composite powders were able to adsorb effectively oil droplets spread on the water interface under a magnetic field (permanent magnet). A good recyclability of the fluorinated composite powders was observed for the adsorption and desorption of the oil even after 11 cycle by the use of the similar magnetic separation technique. In addition to the removal of oil over water interface, the selective removal of fluorinated compounds from water will be demonstrated in this conference. References 1. Sawada H (1996) Chem. Rev. 96:1779-1808. 2. Sawada H (2012) Polym. Chem. 3: 46-65. 3. Oikawa Y, Saito T, Yamada S, Sugiya M, Sawada H (2015) ACS Appl. Mater. Interfaces 7: 13782-13793.
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