Preparation and characterization of hyper-crosslinked resins and nanocomposites

This thesis focuses on the preparation and the adsorption study of innovative hyper-crosslinked (HCL) polymers and nanocomposites. New microporous nanocomposites were prepared including multi-walled carbon nanotubes (MWCNTs) in styrene/vinylbenzyl chloride/divinylbenzene hyper-crosslinked resins. In order to promote the embedding of the MWCNTs within the gel-type precursor, a proper surface modification strategy was set up, based on the grafting of a poly(vinylbenzyl chloride) (PVBC) resin, able to participate to the hyper-crosslinking step, onto the nanotubes surface. After dispersion of the MWCNTs into the monomer mixture, HCL nanocomposites were prepared by suspension polymerization followed by Friedel-Crafts reaction. Volumetric gas adsorption and adsorption from solution analysis revealed that, by addition of the modified MWCNTs, it was possible to modulate the pore size distribution and the adsorption properties of HCL polymers. Then, a new synthetic strategy to obtain HCL polymers and nanocomposites was proposed, based on the bulk prepolymerization of a gel type precursor followed by the traditional Friedel-Crafts alkylation step. The obtained HCL materials showed comparable properties with respect to the corresponding resins obtained by suspension prepolymerization. Moreover, the versatility of the proposed process was demonstrated through the realization of two innovative classes of advanced materials: i) HCL microporous organic polymer nanocomposites (MOPNs) and ii) polymer composites containing HCL resins and nanocomposites as fillers. In particular, MOPNs characterized by different porous structures and adsorption properties were prepared including graphene nanoplatelets (GNP) or surface modified graphene oxide (GO) into a styrene/vinylbenzyl chloride/divinylbenzene matrix. Using surface modified GO grafted with PVBC, microporous nanocomposites based on a styrene/divinylbenzene precursor, i.e. without the chlorinated monomer, were also realized. Their microporosity was only generated during the ...