3-Arm star pyrene-functional PMMAs for efficient exfoliation of graphite in chloroform: fabrication of graphene-reinforced fibrous veils.

3-Arm PMMAs end-functionalized by pyrene were designed as dispersing/stabilizing agents for the liquid-phase exfoliation of graphite in low-boiling point solvents like chloroform. The synthetic procedure comprised ARGET ATRP controlled polymerization, click chemistry and the quaternization reaction of triazole, ensuring tailor-made, well-defined pyrene-functional star PMMAs. Among a series of different pyrene-functional macromolecular topologies, the (PMMA-py2)3 proved the most efficient exfoliation agent giving relatively high graphene concentration (0.

Molecular Modeling Combined with Advanced Chemistry for the Rational Design of Efficient Graphene Dispersing Agents.

Pyrene-functional PMMAs were prepared via ATRP-controlled polymerization and click reaction, as efficient dispersing agents for the exfoliation of few-layered graphene sheets (GS) in easily processable low boiling point chloroform. In parallel, detailed atomistic simulations showed fine dispersion of the GS/polymer hybrids in good agreement with the experiment. Moreover, the molecular dynamics simulations revealed interesting conformations (bridges, loops, dangling ends, free chains) of GS/polymer hybrids and allowed us to monitor their time evolution both in solution and in the polymer nanocomposite where the solvent molecules were replaced with PMMA chains.

Thermo-Resistant Soft Glassy Suspensions of Polymeric Micellar Nanoparticles in Ionic Liquid.

We report the rheological and structural properties of a suspension comprising poly(ethylene oxide)-polystyrene-poly(ethylene oxide) core-shell micellar nanoparticles dispersed in 1-butyl-3-methylimidazolium hexafluorophosphate ionic liquid. A liquid to soft solid transition was observed at a copolymer concentration of 10 wt % above which an elastic soft material was formed, which was composed of non-ordered jammed core-shell micellar nanoparticles. In the soft solid state, a significant reduction in the size of the nanoparticles, approaching hard sphere behavior, was observed by small-angle X-ray scattering which is attributed to compression of the soft poly(ethylene oxide) coronas.