Assessing the transport properties of organic penetrants in low‐density polyethylene using free volume models |
| |
| Authors: | J E Ritums B Neway F Doghieri G Bergman U W Gedde M S Hedenqvist |
| |
| Institution: | 1. School of Chemical Science and Engineering, Fiber and Polymer Technology, Royal Institute of Technology, SE‐100 44 Stockholm, Sweden;2. Corrosion and Metals Research Institute, Drottning Kristinas v?g 48, SE‐114 28 Stockholm, Sweden;3. Department of Chemical Engineering, Mining and Environmental Technologies, University of Bologna, Viale Risorgimento 2, I‐40136 Bologna, Italy;4. School of Chemical Science and Engineering, Fiber and Polymer Technology, Royal Institute of Technology, SE‐100 44 Stockholm, SwedenSchool of Chemical Science and Engineering, Fiber and Polymer Technology, Royal Institute of Technology, SE‐100 44 Stockholm, Sweden |
| |
| Abstract: | Three models, two of them relying on free volume—the Cohen–Turnbull–Fujita (CTF) model and the Vrentas–Duda (VD) model, and the third being empirical using an exponential concentration dependence of the diffusivity, were applied to desorption data for a series of alkane penetrants (2,2‐dimethylbutane, cyclohexane, n‐hexane, n‐decane, and n‐tetradecane) in low‐density polyethylene. The CTF model described the desorption data very well and better than the exponential diffusion law. The VD model with the attractive feature of being based on independently determined parameters was unsuccessful in describing the desorption data. Diffusivity data indicated that the three components outside the crystal core were less accessible to n‐tetradecane than to the other penetrants. This indication was further substantiated by solubility data. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 723–734, 2007 |
| |
| Keywords: | diffusion free‐volume polyethylene theory |
|
|
