Plasma surface modification of polystyrene and polyethylene

Abstract

Polystyrene (PS) and polyethylene (PE) samples were treated with argon and oxygen plasmas. Microwave Electron Cyclotron Resonance (ECR) was used to generate the argon and oxygen plasmas and these plasmas were used to modify the surface of the polymers. The samples were processed at different microwave powers and treatment time and the surface modification of the polymer was evaluated by measuring the water contact angle of the samples before and after the modification. Decrease in the contact angle was observed with the increase in the microwave power for both polystyrene and polyethylene. Plasma parameters were assessed using Langmuir probe measurements.Fourier transform infrared spectroscopy showed the evidence for the induction of oxygen based functional groups in both polyethylene and polystyrene when treated with the oxygen plasma. Argon treatment of the polymers showed improvement in the wettability which is attributed to the process called as CASING, on the other hand the oxygen plasma treatment of the polymers showed surface functionalization. Correlation between the plasma parameters and the surface modification of the polymer is also discussed * Corresponding author: gmrao@isu.iisc.ernet.in

Competitive and synergistic effects between excimer VUV radiation and O radicals on the etching mechanisms of polyethylene and fluoropolymer surfaces treated by an atmospheric He–O2post-discharge

“…In those cases, the treatments were sufficient to abstract H atoms and to form free radicals at or near the surface. Those radicals could then interact to form the crosslinks and unsaturated groups with the chain scission [53]. Due to their too short lifetime, the He2* excimers cannot reach the polyethylene surface.…”

Surface Patterning with Colloidal Monolayers

“…Surface functionalization, related to chemical etching, has been reported to only occur due to water impurities in the argon plasma or by environmental oxygen after the plasma treatment. [211,215] …”

Gas-Phase Surface Engineering of Polystyrene Beads Used to Challenge Automated Particle Inspection Systems

“…Traditional CVD uses heat as the energy source required for functionalization, although CVD variants using plasma or UV light are preferred to functionalize substrates sensitive to heat 22 such as polystyrene. Radio frequency 23 and microwave [24][25] plasma CVD efficiently functionalize polystyrene both at low pressure 3 or atmospheric pressure, 26 using either oxygen (O 2 ), 25,27 argon (Ar), 23,25,[28][29] air 30 or helium/nitrogen mixtures (He/N 2 ) 31 as gas precursors. In order to maximize functional groups retention, keep a better control on the process and save costs, one would prefer to replace plasma CVD by luminous CVD, since the latter employs a lower energy source such as light.…”