Relationships between crystallization behavior and application properties of chemically coupled PAI-PTFE coatings
Researchers found that chemically bonded PAI-PTFE coatings exhibit optimized antifriction properties through controlled cooling behavior and homogenized PTFE distribution.
Poly(tetrafluoroethylene) (PTFE) is well known for its very low friction coefficient and thus widely used for antifriction applications, e.g., sliding lacquers, for many years. Because of the high wear rate and cold flow of the original polymer, PTFE is usually added in higher amounts to other polymer matrices as a lubricant. However, the incompatibility of PTFE requires lots of efforts to perform a homogeneous breaking down of agglomerates and particle distribution as well as dispersion stabilization of the physical mixtures during application and curing. PTFE can be functionalized by high energy irradiation and subsequently compatibilized with a polymer matrix by reactive extrusion resulting in chemical bonding of both polymers via suitable reactive groups.
Event Tip: Anticorrosive Coatings
What principles determine the corrosion of metals and how can protective coatings help to prevent corrosion? In this tutorial, the basics of electrochemical processes will be explained, and typical ingredients and formulation features of corrosion protection coatings will be presented and discussed. We will answer these questions online on 05 Sep 2024 in the EC Short Course “Introduction to Anticorrosive Coatings”.
In this manner, poly(amide imide) (PAI) was coupled to γ-radiation modified PTFE micro-powder prior to the dispersion procedure. This study deals with the thermal and crystallization behavior of the PTFE lubricant in chemical bonded (cb) PAI-PTFEcb compound thin layers in comparison with those of the plain radiation modified PTFE depending on the cooling rate by DSC, Flash-DSC and WAXS. A morphological characterization of the extrudate as well as the coating gives information about the fragmentation and distribution of the PTFE phase in the PAI matrix. Furthermore, mechanical and surface properties of sliding lacquer films were analyzed after application on steel substrates by varying dry film thickness and curing.
Journal of Coatings Technology and Research, Volume 21, pages 623–654, (2024)
