| Autor: |
Alentiev AY; A.V. Topchiev Institute of Petrochemical Synthesis RAS, 119991 Moscow, Russia., Levin IS; A.V. Topchiev Institute of Petrochemical Synthesis RAS, 119991 Moscow, Russia., Belov NA; A.V. Topchiev Institute of Petrochemical Synthesis RAS, 119991 Moscow, Russia., Nikiforov RY; A.V. Topchiev Institute of Petrochemical Synthesis RAS, 119991 Moscow, Russia., Chirkov SV; A.V. Topchiev Institute of Petrochemical Synthesis RAS, 119991 Moscow, Russia., Bezgin DA; A.V. Topchiev Institute of Petrochemical Synthesis RAS, 119991 Moscow, Russia., Ryzhikh VE; A.V. Topchiev Institute of Petrochemical Synthesis RAS, 119991 Moscow, Russia., Kostina JV; A.V. Topchiev Institute of Petrochemical Synthesis RAS, 119991 Moscow, Russia., Shantarovich VP; N.N. Semenov Federal Research Center For Chemical Physics RAS, 119991 Moscow, Russia., Grunin LY; Department of Physics, Volga State University of Technology, 424000 Yoshkar-Ola, Russia. |
| Abstrakt: |
Poly-2,6-dimethylphenylene oxide (PPO) film samples with varying degrees of crystallinity (from 0 to 69%) were obtained by means of different techniques. The films were studied by various physicochemical methods (Fourier-transform infrared spectroscopy, positron annihilation lifetime spectroscopy, X-ray diffraction, and 1 H nuclear magnetic resonance relaxation). Solubility coefficients of gases in the PPO samples were measured via sorption isotherms of gases by volumetric technique with chromatographic detection. The apparent activation energy of permeation and the activation energy of diffusion of all gases were estimated based on temperature dependences of gas permeability and diffusivity for amorphous and semi-crystalline PPO in the range of 20-50 °C. The peculiarities of free volume, density, and thermal properties of gas transport confirm the nanoporosity of the gas-permeable crystalline phase of PPO. So, the PPO can be included in the group of organic molecular sieves. |
