Modification of expanded polytetrafluoroethylene by UV irradiation in reactive and inert atmosphere

VUV treatment combined with mechanical strain of stretchable polymer foils resulting in cell alignment

“…Another study showed that the extreme sensitivity of the soft segments to UV irradiation could be the reason for the rapid degradation of polyether based PU upon exposure to sun [35]. In our previous work, we found that also the VUV light of the 172 nm Xe 2 * excimer lamp can strongly decrease the mechanical stability of polymer materials [36]. To assess the effect of the VUV treatment on the mechanical stability of the PU foils under investigation, we performed tensile tests.…”

Non-thermal ablation of expanded polytetrafluoroethylene with an intense femtosecond-pulse laser

“…In general, processing soft porous materials such as foams and sponges requires precise processing technology. Various techniques have been proposed and investigated for the micromachining of ePTFE, including mechanical processing, synchrotron radiation [2], and nanosecond laser ablations [3,4]. However, sufficiently precise processing has not been realized due to the low melting temperature of ePTFE (T m = 327°C) and its non-uniform bond strength due to its surface roughness [5].…”

Photochemical surface modification of polymers for biomedical applications

“…The high wettability of treated surfaces is ascribed to polar groups incorporated into the PTFE surface by substitution of F atoms. The subtraction of F is mediated via atomic H which is generated in the dissociation reaction NH 3 + hν → NH 2 + H [15]. An irradiation in 5 mbar C 2 H 2 leads to effective photo-dissociation, resulting in the deposition of polymerized a:C-H (amorphous hydrogenated carbon) films at polymer samples placed in the reactor [17].…”