Abstract
A method is proposed for calculating thermodynamic characteristics of flexible lattice model chains of finite length in slit pores with arbitrary energy of interaction between chain units and the pore surface. Molecular weight dependences were calculated for the combined state of chains with pore surface θ N and the free conformation energy of chains in pores F N . It was confirmed that the critical energy which separates molecular-sieve and adsorption ranges in chromatography of polymers is independent of chain length (number of N units) and pore width D. It was found that θ N and F N / N reach limiting asymptotic values in the adsorption region, independent of pore width and are only determined by the energy of adsorption, while in the exclusion region, 1when adsorption effects are suppressed, only depend on the ratio of chain dimensions and pore width. For short chains (or wide pores) F N ∼ ( R 2) 1 2 /D , while for long molecules, F N ∼ R 2/D 2 ( R 2 is the rms radius of inertia of macromolecules). Transition from one dependence to the other takes place when ( R) 2 1 2 D≅0·11 . Experimental results were analysed by chromatography of dextran on porous glass and these results confirmed theoretical predictions.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
