New Generation of Hybrid Organic-Inorganic Macrocellular Foams: Integrative Chemistry Toward Reaching Multifunctional Ma
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1007-S04-06
New Generation of Hybrid Organic-Inorganic Macrocellular Foams: Integrative Chemistry toward Reaching Multifunctional Materials Simona UNGUREANU1, Hervé DELEUZE2, Marc BIROT2, Clément SANCHEZ3, and Rénal BACKOV1 1 C.R.P.P. CNRS UPR 8641, 115 Ave. Albert Schweitzer, Pessac, F-33600, France 2 ISM-UMR CNRS 5802, Université Bordeaux-I, 351 cours de la Libération, Talence, 33045, France 3 LCMCP UMR CNRS 7574, Université Pierre et Marie Curie, 4 place Jussieu, Tour 54, E. 5, Couloir 54-55, Paris, 75252, France
ABSTRACT The elaboration of organosilica based hybrid monoliths exhibiting a hierarchically structured bimodal porous structure with tunable functionality have been processed via High Internal Polymeric Emulsion (HIPE) process for the first time. Through one pot synthesis, many organic functionalities that can act as network modifiers (Methyl, Dinitrophenylamino, Benzyl, Mercaptopropyl) or co-network formers (Pyrrol) have been anchored to the amorphous silica porous network. The resulting materials have been thoroughly characterized via a large set of techniques SEM, TEM, SAXS, mercury porosimmetry, nitrogen adsorption isotherms, FTIR, 29 Si MAS NMR. These sol-gel derived hierarchical open cell functional hybrid monoliths exhibit macroscopic void spaces ranging from 5 up to 30 µm and their accessible micro-mesoporosity, reveal hexagonal organisation for the dinitrophenylamino, benzyl, and pyrrol based hybrids. The average condensation degree for these hybrid networks ranges between 86 and 90% yielding shaped monoliths with both good integrity and sufficient mechanical properties to be usable as functional catalytic or chromatographic supports. INTRODUCTION Bio-inspired approach and induced bio-inspired materials has open new chemical strategies by combining mainly sol-gel or mineralization processes with templated growth [1]. The use of lyotropic mesophases, (biological or not), micro-emulsion and external solicitations allows thus through an intelligent and tuned coding, to develop innovative materials possessing complex hierarchical architectures. Current approaches to hierarchically structured inorganic materials include coupling of multiscale templating that makes the use of self-assembled surfactant with larger templates as emulsion droplets [2], foams [3], latex beads [4] bacterial threads [5], organogelators [6], controlled phase segregation [7], and so forth. Recently, the interface between bio-inspired approaches, hybrid organic-inorganic chemistry, when extended to both soft chemistry in general (including organic polymer and supra-molecular chemistry) and complex fluids, was coined “integrative chemistry”[8] where chemistry and process are strongly
coupled. More importantly, the assembling of a large variety of molecular precursors or nanobuilding blocks, though the “integrative chemistry” approach, into engineered hierarchical structures (bio-inspired or not) should be strongly pre-dictated in view of final function or polyfunctionalities to be reached and not vice versa. Particularly, or
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