The crystallinity of chemically bonded PA-PTFE-oil compounds by X-ray diffraction and DSC

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Thanh Duong Nguyen - , Chair of Organic Chemistry of Polymers, Leibniz Institute of Polymer Research Dresden (Author)
  • Negin Farshchi - , Chair of Polymer Materials, Leibniz Institute of Polymer Research Dresden (Author)
  • Tim Johannes Thomas Ulbricht - , Leibniz Institute of Polymer Research Dresden (Author)
  • Anne-Katrin Leopold - , Chair of Polymer Materials, Leibniz Institute of Polymer Research Dresden (Author)
  • Thomas Schmidt - , Leibniz Institute of Polymer Research Dresden (Author)
  • Kai Uhlig - , Leibniz Institute of Polymer Research Dresden (Author)
  • Markus Stommel - , Chair of Polymer Materials, Leibniz Institute of Polymer Research Dresden, TUD Dresden University of Technology (Author)
  • Brigitte Voit - , Chair of Organic Chemistry of Polymers, Leibniz Institute of Polymer Research Dresden, TUD Dresden University of Technology (Author)
  • Michaela Gedan-Smolka - , Leibniz Institute of Polymer Research Dresden (Author)

Abstract

One of the major shortcomings of compounding polyamide (PA), polytetrafluoroethylene (PTFE), and olefinic oils is the fact that they are incompatible. To overcome this issue, using energy radiation in the presence of oxygen leads to the breakage of the PTFE chain to generate hydrophilic functional groups (COF, COOH) and peroxy radicals. The created functional groups and radicals can be used to induce a chemical bond between PA and PTFE as well as between PTFE and olefinic oil molecules. In addition, the hardness of compounds significantly influences the application of materials as solid-lubricant. It is well known that crystallinity affects the hardness of materials. In the presented study, the effects of the chemical bonding PA-PTFE/PA-PTFE-oil on the crystallization behavior of various types of PA in chemically bonded PA-PTFE-oil-chemically bonded compounds, which were prepared by reactive two-step extrusion, were investigated via DSC and X-ray diffraction. The crystallite size of PA46 and PA66 in PA-PTFE-chemically bonded (cb) compounds was significantly increased compared with pure PA. At the same time, the d-spacings of the PA segment in PA-PTFE compounds were significantly narrower. Due to the chemical coupling, the compounds showed a slight change in hardness compared with pure PA.

Details

Original languageEnglish
Pages (from-to)1828-1842
Number of pages15
JournalJournal of Polymer Science
Volume61
Issue number16
Early online dateMar 2023
Publication statusPublished - 15 Aug 2023
Peer-reviewedYes

External IDs

Scopus 85151422852
ORCID /0000-0002-4531-691X/work/148608052
unpaywall 10.1002/pol.20230035
Mendeley 7d20f834-0f5e-3bd6-849b-63dd9ce8c673

Keywords

Keywords

  • Chemically bonded polyamide-polytetrafluoroethylene-oil, Crystallization, Hardness, Mechanical properties, chemically bonded polyamide-polytetrafluoroethylene-oil, crystallization, hardness, mechanical properties