Surface reaction on polyvinylidenefluoride (PVDF) irradiated by low energy ion beam in reactive gas environment

Abstract

Polyvinylidenefluoride (PVDF) was irradiated by a keV Ar ϩ ion in O 2 environment for improving adhesion between PVDF and Pt, and reaction between PVDF and the ion beam has been investigated by X-ray photoelectron spectroscopy (XPS). The adhesion test between Pt and the modified PVDF was carried out by boiling test, in which the specimens were kept in boiling water for 4 h. Two failure modes (buckling up due to weak adhesion and crack formation due to strong adhesion) of Pt films have been observed in the system. Contact angle of PVDF was reduced to 31 from 75°by the irradiation of 1 ϫ 10 15 Ar ϩ ions/cm 2 with oxygen flow rate of 8 sccm. The surface of the irradiated PVDF became more rough as ion dose increased. The improved adhesion mechanism and identification of newly formed chemical species have been confirmed by Carbon 1s and Fluorine 1s X-ray photoelectron core-level spectra. The main reaction occurred at the irradiated PVDF surface is an ion-beam-induced oxidation accompanied with preferential sputtering of fluorine. Newly formed chemical species at interface are regarded as ester and carboxyl groups. Adhesion of the Pt-PVDF interface was improved by ion irradiation in O 2 environment. This improvement is originated from the presence of carbon-oxygen bonds on the irradiated PVDF surface. Comparison of failure modes on the irradiated PVDF at various conditions after the boiling test shows that adhesion of Pt film is largely affected by the product of ion-assisted reaction.

Surface modification of polyfluoroolefin films by glow discharge

“…It should be noted that dc discharge treatment results in smaller contact angles and higher adhesion works and surface energies than other known methods of polyfluoroolefin modifications [1][2][3][4][5][6][7][8][9]25].…”

“…treatment on the anode [9]; similar results were also obtained with F4MB and F50. With PVDF films lower θ values were obtained on their treatment on the cathode [20]; the same was the case with F62 and F40.…”

“…This result is probably explained by the fact that the surface roughness enhanced due to etching, whereas its chemical composition remained almost the same. At the same time, treatment of poly(vinylidene fluoride) (PVDF) films in the afterglow of an oxygen plasma [8], as well as their bombardment with argon ions [9] decreased the contact angle from 90° to 71° and 31°, respectively.…”

Integration of Polypyrrole Electrode into Piezoelectric PVDF Energy Harvester with Improved Adhesion and Over-Oxidation Resistance

“…Despite these advances, there are obstacles preventing the use of PPy as an electrode material for PVDF, such as the weak adhesion force between the PVDF and PPy. PVDF is a fluorocarbon material with a very low surface energy that adheres poorly to other materials [20,21,22,23]. It has also been reported that the adhesion force between the PPy and hydrophobic surfaces is weak [24,25].…”

Modification effects of amphiphilic comb-like polysiloxane containing polyether side chains on the PVDF membranes prepared via phase inversion process

“…As a result, modifications to improve the hydrophilicity are urgently required for preparing PVDF membranes with outstanding performance characteristics [1][2][3]. At present, the main modification methods focus on surface modification [4][5][6][7] and blending with hydrophilic components [8][9][10][11]. Among the various surface modification methods, smearing glycerol or surfactant has short-term modification effect and may lead to filtrates with high organic concentration.…”