10 research outputs found
Influence of mean distance between fibers on the effective gas thermal conductivity in highly porous fibrous materials
This work was supported by the Russian Goverment Grant No. 14.Z50.31.0036.Peer reviewedPostprin
Production of Molecular Composites Based on Polytetrafluoroethylene and Titanium Dioxide
Structure of ultradispersed powders obtained by thermal decomposition of ftoroplast-4 in presence of ammonium hydrogen difluoride
Application of Low-Temperature Postradiation Polymerization of Polytetrafluoroethylene for Hydrophobization of Porous Ceramic Materials Based on Oxide Fibers
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 F2 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. © 2011 Wiley Periodicals, Inc.SCOPUS: ar.jinfo:eu-repo/semantics/publishe