Predicting solubility and diffusivity of gases in polymers under high pressure: N2 in polycarbonate and poly(ether-ether-ketone)Show others and affiliations
2013 (English)In: Industrial & Engineering Chemistry Research, ISSN 0888-5885, E-ISSN 1520-5045, Vol. 52, no 26, p. 8655-8663Article in journal (Refereed) Published
Abstract [en]
The aim of this study was to develop a model that predicts the gas solubility and the sorption and desorption kinetics in polymer granulates over large temperature and pressure intervals. Besides the part predicting the solubility and diffusivity, the model involves the simultaneous solution of the diffusion equation and the heat equation in three dimensions using a finite element method (FEM). When the temperature- and pressure-dependent solubility of a specific polymer/gas combination is not known, an improved version of the non-equilibrium lattice fluid model (NELF) is used to predict the solubility. The improvement of the NELF model includes the use of Hansen's solubility parameters, and it uses pressure-volume-temperature (PVT) data from two new empirical models, which accurately estimate polymer densities over a wide range of temperatures and pressures. The new solubility model predicted the solubility-pressure data of N2 in poly(ethyl methacrylate) and N 2 and CH4 in polycarbonate (PC) at pressures below 4.5 MPa, without using any adjustable interaction parameters. The model was used to predict the solubility of N2 in poly(ether-ether-ketone) (PEEK) and PC at a very high pressure (67 MPa). Experimental N2 solubility data were obtained with a specially built reactor yielding high pressure and temperature. For PEEK, it was possible to predict the very high pressure solubility using a gas-polymer interaction parameter obtained from data taken at low pressures. In addition, a new free-volume-based diffusivity model requiring no adjustable interaction parameters was developed, and it successfully predicted the desorption kinetics of N2 from PEEK and PC.
Place, publisher, year, edition, pages
2013. Vol. 52, no 26, p. 8655-8663
Keywords [en]
Desorption, Diffusion, Ethers, Forecasting, Ketones, Partial differential equations, Polycarbonates, Polymers
National Category
Natural Sciences
Identifiers
URN: urn:nbn:se:ri:diva-26571DOI: 10.1021/ie300975hScopus ID: 2-s2.0-84879862466OAI: oai:DiVA.org:ri-26571DiVA, id: diva2:1053574
Note
A3210
2016-12-082016-12-082021-06-18Bibliographically approved