Chain mobility in polymer systems : on the borderline between solid and melt 3. Phase transformations in nascent ultrahigh molecular weight polyethylene reactor powder at elevated pressure as revealed by in-situ Raman spectroscopy

L. Kurelec, S. Rastogi, R.J. Meier, P.J. Lemstra

    Research output: Contribution to journalArticleAcademicpeer-review

    78 Citations (Scopus)
    2 Downloads (Pure)

    Abstract

    The phase transformations under elevated pressure have been followed in situ by X-ray and Raman spectroscopy for ultrahigh-molecular-weight polyethylene (UHMW-PE) reactor powder. Using the in situ X-ray as a reference for the Raman work, it has been shown that Raman spectroscopy is a convenient method to follow phase transformations in polyethylene under pressure. The distinction has been made between different solid phases in polyethylene (monoclinic, orthorhombic, and hexagonal phases) and the melt by studying the conformational changes occurring within the skeletal mode (1000-1200 cm-1) upon the phase transformations. The crystal field splitting (1415/1440 cm-1) in the -CH2- bending mode of the Raman spectrum of polyethylene, related to the orthorhombic unit cell, was confirmed to be sensitive to transformations between different crystal structures. By following the changes occurring in the methylene bending mode together with the changes within the C-C skeletal mode, it has been shown that the crystalline phases and the melt can be mutually distinguished.
    Original languageEnglish
    Pages (from-to)5593-5601
    Number of pages8
    JournalMacromolecules
    Volume33
    Issue number15
    DOIs
    Publication statusPublished - 2000

    Fingerprint Dive into the research topics of 'Chain mobility in polymer systems : on the borderline between solid and melt 3. Phase transformations in nascent ultrahigh molecular weight polyethylene reactor powder at elevated pressure as revealed by in-situ Raman spectroscopy'. Together they form a unique fingerprint.

    Cite this