Photoactivated surface grafting from PVDF surfaces

Abstract

International audienceEconomic and easy methods to tune surface properties of polymers as Poly(vinylidene fluoride) (PVDF) without altering bulk properties are of major interest for different applications as biotechnological devices, medical implant device. . . UV irradiation appears as one of the simplest, easy and safe method to modify surface properties. In the case of self-initiated grafting, it is generally assumed that the pretreatment of the PVDF surface with UV irradiation can yield alkyl and per-oxy radicals originating from breaking bonds and capable of initiating the subsequent surface grafting polymerizations. Surprisingly, the present work shows that it is possible to obtain polymer grafting using low energetic UV-A irradiation (3.1-3.9 eV) without breaking PVDF bonds. An EPR study has been performed in order to investigate the nature of involved species. The ability of the activated PVDF surface to graft different kinds of hydrophilic monomers using the initiated surface polymerization method has been tested and discussed on the basis of ATR FT-IR, XPS and NMR HRMAS results

Structure and pH‐sensitive properties of poly (vinylidene fluoride) membrane changed by blending poly (acrylic acid) microgels

“…The two peak components of about equal intensities (with BEs at 286.2 eV for the CH 2 species and at 290.6 eV for the CF 2 species) are assigned to the PVDF main chains. The new peaks with the BEs at 288.5, 286.2 and 284.8 eV are, respectively, assigned to the O–C = O species, the CO species whose BE is equal to that of CH 2 (PVDF) and the hydrocarbon backbone of the PAA microgels …”

Novel PVDF-g-NMA Copolymer for Fabricating the Hydrophilic Ultrafiltration Membrane with Good Antifouling Property

“…The improvement in the hydrophilicity of the PVDF membrane is generally considered to be a solution to the problem of membrane fouling, which minimizes the interaction of polymer and foulants. , In recent decades, PVDF membrane has a variety of hydrophilic modifications. Surface modification does not change the properties of the pristine membrane, which maintains good mechanical property and chemical stability. − In blending modification, membrane’s hydrophilic property is improved by the addition of hydrophilic polymer, inorganic nanoparticles, and amphiphilic copolymer, thereby improving the antifouling performance of the PVDF membrane. − The addition of amphiphilic copolymers can improve the hydrophilicity of the PVDF membrane, where hydrophilic chains spontaneously migrate to membrane’s surface due to self-assembly effects . Amphiphilic copolymers, such as PVDF- g -poly­(oxyethylene methacrylate) (PVDF- g -POEM), PVDF- g -4-methacrylamidobenzenesulfonic acid (PVDF- g -PMABS), PVDF- g -poly­(ethylene glycol) methyl ether methacrylate (PVDF- g -PEGMA), PVDF- g -polyacryloylmorpholine (PVDF- g -PAMCO), and PVDF- g -(polyacryloylmorpholine-(polyacrylic acid)) (PVDF- g -(PAMCO-PAA)), have been successfully synthesized, which effectively improve the hydrophilic and antifouling properties of PVDF membranes. − In addition, the higher the viscosity of the PVDF casting solution, the more difficult it is to defoam.…”

Electron beam modification of anode materials for high-rate lithium ion batteries

“…The highly electronegative fluorine substituents shift the binding energy of the C 1s level, and the C 1s spectrum of PVDF contained two main peaks at 285.8 and 290.2 eV corresponding to the CH 2 and CF 2 groups, respectively. An additional two peaks were also apparent at 287.8 and 292 eV for CF 2 eCOeCH 2 (CF 2 eCOeCF 2 ) and CF 3 , respectively [16,17]. After EB irradiation, a new peak at approximately 282 eV was observed, which was attributed to eHeCeCeFe produced by crosslinking during EB irradiation [18].…”