Free volume and transport properties of homogeneous poly (ethylene-co-octene)s
2004 (English)In: Polymer, ISSN 0032-3861, E-ISSN 1873-2291, Vol. 45, no 11, 3913-3922 p.Article in journal (Refereed) Published
Liquid and vapour n-hexane sorption/desorption were studied on homogeneous poly(ethylene-co-octene)s produced by metallocene-catalyzed polymerisation covering a crystallinity range from 3.5 to 72.4%. Crystal core contents determined by Raman spectroscopy were lower than those determined by density assessments, particularly at low degrees of crystallinity. The solubility showed deviation from Henry's law. The solubilities of n-hexane in the homogeneous copolymers depended in a non-linear manner on the content of penetrable polymer component and were lower than those earlier reported for heterogeneous copolymers at the same contents of penetrable component. The concentration dependence of the thermodynamic diffusivity predicted by the Cohen-Turnbull-Fujita free volume theory was confirmed by the data obtained by the differential method and the differences between the results obtained from the integral and differential methods were within the margins of experimental error. The fractional free Volume of the penetrable polymer fraction increased with increasing fraction of penetrable polymer and with relative proportion of liquid-like component in the penetrable polymer fraction. The homogeneous copolymers showed a decreasing trend in the geometrical impedance factor with increasing degree of crystallinity.
Place, publisher, year, edition, pages
2004. Vol. 45, no 11, 3913-3922 p.
n-hexane diffusion, poly(ethylene-co-octene), free volume, molecular-dynamics simulation, semicrystalline polymers, penetrant diffusion, polyethylene, morphology, desorption, liquids, dependence, transition, membranes
IdentifiersURN: urn:nbn:se:kth:diva-23425DOI: 10.1016/j.polymer.2003.12.083ISI: 000221486300040ScopusID: 2-s2.0-2342662625OAI: oai:DiVA.org:kth-23425DiVA: diva2:342123
QC 20100525 QC 20111020. Symposium on Coupling Simulations and Experiments in Polymer Science. Univ Utah, Salt Lake City, UT. MAY 15-17, 20032010-08-102010-08-102011-10-25Bibliographically approved