Modification of Ultra-High-Molecular Weight Polyethylene by Various Fluorinating Routes

Chemical-physical properties of ultra-high-molecular weight polyethylene (UHMWPE) treated by direct fluorination, direct fluorination accompanied with UV irradiation, by XeF2 and by TbF4, were tested by FTIR spectroscopy, visible spectroscopy, 19F and 13C NMR, scanning electron microscopy, XRD, and EPR. Surface energy measurements were carried out. The direct fluorination of UHMWPE is a diffusion-controlled process, but treatment with XeF2 is a kinetically controlled one. Direct fluorination and direct fluorination accompanied with UV irradiation results mainly in a formation of-CF2-groups. On the contrary, -CHF- groups are prevailing in UHMWPE treated with XeF2 and TbF4. Surface texture of UHMWPE treated with XeF2 and with F-2 is quite different. Direct fluorination results in a higher polarity of the polymer surface when compared with treatment with XeF2. For the case of direct fluorination, both long-lived peroxy and fluoroalkylradicals are formed. For the case of treatment with XeF2, only fluoroalkylradicals were detected. (C) 2011 Wiley Periodicals, Inc. J PolymSci Part A: PolymChem 49: 3559-3573, 2011