Electrical and other properties of mutual radiation‐induced methacrylic acid grafted polyethylene films

Abstract

SynopsisThe radiation-induced grafting of methacrylic acid onto polyethylene films was applied to the synthesis of ion-exchange membranes. The grafting yield increased at first then decreased with the increase in the irradiation dose. The surface area, thickness, volume, and the water uptake of the grafted film increased linearly with the increase in grafting yield. The distribution pattern of carboxyl groups of graft chains in the direction of film thickness followed by EPMA line profiles of potassium which combined with carboxyl groups showed that a homogeneous distribution was not obtained until the grafting yield was more than 10%. When DC current was supplied to the membrane in NaOH solution, the reciprocal of the electric resistance increased with the increase in NaOH concentration. The specific electric resistance decreased exponentially with the increase in the content of ionic functional groups in the membrane. The steady state concentration of Na+ in catholyte and the current efficiency were ca. 15 and 20%, respectively.

Ion exchange membranes: State of their development and perspective

“…In such route, two functional acidic groups were mainly identified as fixed ionic groups that confer the membrane its cation character, namely carboxylic (weakly acidic) and sulfonic acid (strongly acidic) groups. The former can be prepared either by direct grafting of acrylic monomers like acrylic [40][41][42][43][44], methacrylic acids [45][46][47][48][49] and their mixtures with acrylonitrile [50,51] and vinylacetate [52] or by grafting of epoxy acrylate monomers, such as glycidyl acrylate or glycidyl methacrylate onto polymer films followed by the conversion of the epoxy group into carboxylic group, such as iminodiacetate groups which were obtained by post-grafting ring opening reaction [53]. Strongly acidic membranes are commonly prepared by grafting of styrene onto polymer films and the resulted graft copolymer films are subsequently sulfonated [54][55][56][57][58][59][60][61].…”

Development of Membranes by Radiation‐Induced Graft Polymerization of Monomers onto Polyethylene Films

“…The x-ray microprobe analysis (XMA) has been very useful in investigating the graft distribution as observed in methacrylic acid grafted PE films. [59] Sugiyama et al [61] carried out the grafting of sodium styrenesulfonate and acrylic acid mixture into PE hollow fibre and films. The cross-sections of grafted matrix were analyzed by SEM and XMA.…”

Hydrophilic and adhesive properties of methacrylic acid‐grafted polyethylene plates

“…Omichi et al studied the radiation-grafting of MAA to PE films and found that the water uptake increased linearly with the grafting yield. 16 Hegazy et al studied the preirradiation-grafting of AA into poly ( tetrafluoroethylene-hexafluoropropylene) films and reported that no effect of grafting conditions such as preirradiation dose, grafting temperature, and monomer concentration on the swelling behavior was observed and the degree of swelling depended mainly on the amount of the hydrophilic group in the films.17 For the grafted PE plates prepared at lower monomer concentrations, the amount of water per monomer segment increased gradually and then increased drastically with the grafted amount. On the other hand, for the PE plates grafted at higher monomer concentrations above 1.2 mol/dm3, no such behavior was observed.…”