No CrossRef data available.
Article contents
Translational and Rotational Motion of Small Penetrants in AF1600 Nanocomposites
Published online by Cambridge University Press: 26 February 2011
Abstract
Translational and rotational motions of dichloromethane were observed in a composite of poly(2,2-bis(trifluoromethyl)-4,5-difluoro-1,3-dioxole-co-tetrafluoroethylene), also referred to as AF1600, with fumed silica using NMR. Pulsed field gradient diffusion measurements show that adding fumed silica to AF1600 results in a great enhancement of the diffusion coefficient of dichloromethane. The diffusion enhancement behavior is similar to that previously reported in pentane, cyclohexane, and toluene in AF1600 nanocomposites. Spin-lattice relaxation time measurements of this system indicate two domains: one containing larger free volume elements (FVEs) that support faster dynamics and one containing smaller free volume elements that support slower dynamics. Adding the fumed silica disrupts the packing of polymer chains resulting in an increase of free volume and improved connections between domains supporting rapid translation. The lattice model simulation is performed to assist in understanding the mechanism of how the addition of fumed silica improves penetrant diffusion in nanocomposite polymer systems.
- Type
- Research Article
- Information
- Copyright
- Copyright © Materials Research Society 2007