title: Effect of thermally reduced graphene sheets on the phase behavior, morphology, and electrical conductivity in poly[(α-methyl styrene)-co-(acrylonitrile)/poly(methyl-methacrylate) blends.
abstract: The effects of thermally reduced graphene sheets (TRG) on the phase separation in poly[(α-methyl styrene)-co-(acrylonitrile)]/poly(methyl-methacrylate) blends were monitored using melt rheology, conductivity spectroscopy, and electron microscopic techniques. The TRG were incorporated in the single-phase material by solution mixing. The composite samples were then allowed to phase separate in situ. The thermodynamics of phase separation have been investigated by monitoring the evolution of the storage modulus (G') as a function of temperature as the system passes through the binodal and the spinodal lines of the phase diagram. The phase separation kinetics were probed by monitoring the evolution of G' as a function of time at a quench depth well in the spinodal region. It was observed that TRG significantly influenced the phase separation temperature, the shape of the phase diagram and the rate of phase separation. The state of dispersion of TRG in the blends was assessed using electron microscopy and conductivity spectroscopy measurements. Interestingly, the composite samples (monophasic) were virtually insulators at room temperature, whereas highly conducting materials were obtained as a result of phase separation in the biphasic materials.
authors: Department of Chemical Engineering and Leuven Materials Research Center, Katholieke Universiteit Leuven, Willem de Croylaan 46, B-3001, Leuven, Belgium.
authors: Giovanni
authors: G
authors: Vleminckx
authors: Suryasarathi
authors: S
authors: Bose
authors: Jan
authors: J
authors: Leys
authors: Jan
authors: J
authors: Vermant
authors: Michael
authors: M
authors: Wübbenhorst
authors: Ahmed A
authors: AA
authors: Abdala
authors: Chris
authors: C
authors: Macosko
authors: Paula
authors: P
authors: Moldenaers
mesh_terms: D004553:Electric Conductivity; D006108:Graphite / Q000737:chemistry*; D007700:Kinetics; D008854:Microscopy, Electron; D019904:Polymethyl Methacrylate / Q000737:chemistry*; D011137:Polystyrenes / Q000737:chemistry*; D013696:Temperature; D013816:Thermodynamics
chemical_list: D011137:Polystyrenes; D006108:Graphite; D019904:Polymethyl Methacrylate