Article

Functionalisation of polypropylene non-woven fabrics (NWFs)

Journal of Thermal Analysis and Calorimetry (Impact Factor: 1.98). 109(2):1-14. DOI: 10.1007/s10973-011-1940-8

ABSTRACT Surface oxyfluorination had been carried out on polypropylene non-woven fabric (PP NWF) samples of different morphologies
and pore sizes. The modified surfaces were characterised by Attenuated Total Reflectance Fourier Transform InfraRed (ATR-FTIR)-spectroscopy,
FTIR imaging microscopy, X-Ray Photoelectron Spectroscopy (XPS), Electron Spin Resonance (ESR) spectroscopy, Differential
Scanning Calorimetry (DSC), X-Ray Diffraction (XRD) analysis, Scanning Electron Microscopy (SEM), dynamic rheometry and Thermo-Gravimetry
(TG). ATR-FTIR and XPS techniques revealed the presence of –CF, –CF2, –CHF and –C(O)F groups. The formed –C(O)F groups mostly got hydrolysed to –COOH groups. The C=O groups of alpha-haloester,
and the C=C stretching of the formed –CF=C(OH)– groups could also be detected. Long-lived radicals could be detected on the
functionalised surfaces as middle-chain peroxy radicals by ESR spectroscopy. SEM micrographs showed slight roughening of the
oxyfluorinated surfaces. Oxyfluorination had no significant effect on the crystalline structure and phase composition of the
PP NWF samples supported by DSC and XRD measurements. The molecular mass of the samples were unaffected by the oxyfluorination
treatment as proved by oscillating rheometry. The surface modification, however, significantly affected the thermal decomposition
but not affected the thermo-oxidative decomposition of PP NWFs. Different morphologies and pore sizes of PP NWF samples resulted
in reproducibility of the findings, although did not substantially affect surface functionalisation.

KeywordsOxyfluorination–PP non-woven fabrics–ATR-FTIR–FTIR-imaging–XPS–ESR–SEM–DSC–WAXS–Dynamic rheometry–TG

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