Ageing processes of alkyl bonded phases in HPLC; a chromatographic and spectroscopic approach

Abstract

Document VersionPublisher's PDF, also known as Version of Record (includes final page, issue and volume numbers)Please check the document version of this publication:• A submitted manuscript is the author's version of the article upon submission and before peer-review. There can be important differences between the submitted version and the official published version of record. People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website.• The final author version and the galley proof are versions of the publication after peer review.• The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publication Citation for published version (APA):Claessens, H. A., Cramers, C. A. M. G., Haan, de, J. W., Otter, den, F. A. H., Ven, van de, L. J. M., Andree, P. J., ... Zeeman, J. (1985). Ageing processes of alkyl bonded phases in HPLC; a chromatographic and spectroscopic approach. Chromatographia, 20(10), 582-586. DOI: 10.1007/BF02263215General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.• Users may download and print one copy of any publication from the public portal for the purpose of private study or research.• You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal ? Take down policyIf you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. Key WordsReversed-phase HPLC Ageing processes Solid state NMR FTIR Chain dynamics Summary Laboratory use of HPLC columns packed with C8 and C18 bonded phases leads to changes in selectivities and retention volumes. FTI R, 1 H N M R of hydrolysed bonded phases and solid state 13C-and 29Si NMR were applied to characterize the materials. The results of the various techniques are in fair agreement except solid state NMR. Loss of silane and hydrolysis of surface siloxane groups have been observed for the C8 bondes phase, while for the C18 material the latter process seems to dominate. The solid state NMR results have been tentatively explained in terms of changing chain arrangements and mobilities.

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