Effects of film thickness on density and gas permeation parameters of glassy polymers |
| |
Authors: | AM Shishatskii YuP Yampol'skii K-V Peinemann |
| |
Institution: | 1. A.V. Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, 29, Leninsky Pr., 117912, Moscow, Russian Federation;2. GKSS Forschungszentrum, Geesthacht, Max-Planck-Str., 21502 Geesthacht, Germany |
| |
Abstract: | Dense films of poly(vinyltrimethyl silane) (PVTMS) and poly(trimethylsilyl norbornene) (PTMSNB) having different thicknesses in the range l = 5–150 μm were cast from hydrocarbon solutions. It was shown that a density is inversely proportional to the film thickness. The following equation holds for the density ?: 1/? = 1/?0 − b/l. Permeability and diffusion coefficients were determined using the time lag method in respect to different gases. For all the gases, diffusion coefficients decrease when film thickness decreases and film density increases. A correlation of diffusion coefficients with fractional free volume were demonstrated. On the other hand, permeability coefficients are nearly independent of the thickness and density. Possible mechanisms of this behavior are discussed. |
| |
Keywords: | Density Diffusion coefficient Permeability Poly(vinyltrimethyl silane) Poly(trimethylsilyl norbornene) |
本文献已被 ScienceDirect 等数据库收录! |
|