Tailoring bulk and surface grafting of poly(acrylic acid) in electron-irradiated PVDF

Marie-Claude Clochard (1) , J Bègue (1) , A Lafon (1) , D Caldemaison (2) , C Bittencourt (3) , J.-J Pireaux (3) , N Betz (1)

1 LSI - Laboratoire des Solides Irradiés - Irradiated Solids Laboratory
2 LMS - Laboratoire de mécanique des solides
3 LISE

Endowing conventional hydrophobic poly(vinylidene fluoride) (PVDF) films with hydrophilic properties was conducted using electron beam irradiation. Grafting of acrylic acid (AA) in/onto pre-irradiated PVDF films was investigated. Reaction parameters, monomer concentration and inhibitor concentration were examined. Radiation grafted films (PVDF-g-PAA) were synthesized with various grafting yields ranging from 12 to 130 wt % in presence of Mohr's salt (25 wt %). Below 80 wt % of monomer concentration, the degree of swelling was found to increase with the grafting yield. The PAA was arranged randomly in all PVDF matrix (grafting through). Above 80 wt % of monomer concentration, the PAA was grafted only onto the surface of PVDF films leading to a highly dense layer of PAA. Grafting through or surface grafting processes were achieved by varying the water fraction in the initial monomer solution. Water molecule acts not only as a carrier for the monomer but also as a plasticizer expanding the film in the three dimensions. Evidences of grafting through and surface grafting were produced using FTIR in ATR mode, SEM coupled to X-ray detection and XPS. An accurate quantification of AA units was possible up to the micromole via a Cu 2C –EDTA complex analyzed by UV–vis spectroscopy. q

Mots clés: Acrylic acid; Radiation grafting; PVDF

Domaines: Polymères

Marie-Claude Clochard, J Bègue, A Lafon, D Caldemaison, C Bittencourt, et al.. Tailoring bulk and surface grafting of poly(acrylic acid) in electron-irradiated PVDF. Polymer, 2004, 45, pp.8683. ⟨10.1016/j.polymer.2004.10.052⟩. ⟨hal-01129036⟩