Surface Activation of Poly(Methyl Methacrylate) with Atmospheric Pressure Ar + H2O Plasma

Essam Abdel–Fattah

doi:10.3390/coatings9040228

Abstract

The atmospheric pressure of Ar + H 2 O plasma jet has been analyzed and its effects on the poly(methyl methacrylate) (PMMA) surface has been investigated. The PMMA surface treatment was performed at a fixed gas flow-rate discharge voltage, while varying the plasma treatment time. The Ar + H 2 O plasma was studied with optical emission spectroscopy (OES). Optimum plasma conditions for PMMA surface treatment were determined from relative intensities of Argon, hydroxyl radical (OH), oxygen (O) I emission spectra. The rotational temperature T rot of Ar + H 2 O plasma was determined from OH emission band. The PMMA surfaces before and after plasma treatment were characterized by contact angle and surface free energy measurements, X-ray photoelectrons spectroscopy (XPS), atomic force microscope (AFM) and UV-spectroscopy. The contact angle decreased and surface free energy increased with plasma treatment time. XPS results revealed the oxygen to carbon ratio (O/C) on plasma-treated PMMA surfaces remarkably increased for short treatment time ≤60 s, beyond which it has weakly dependent on treatment time. The carbon C1s peak deconvoluted into four components: C–C, C–C=O, C–O–C and O–C=O bonds and their percentage ratio vary in accordance with plasma treatment time. AFM showed the PMMA surface roughness increases with plasma treatment time. UV-visible measurements revealed that plasma treatment has no considerable effect on the transparency of PMMA samples.

Highlights

Polymethyl methacrylate (PMMA) has attracted more and more attention in various industrial applications due to its low cost, ease of processing, excellent physical and chemical properties [1]
Its light transmittance is similar to glass, its mechanical properties such as rigidity and low density make poly(methyl methacrylate) (PMMA) more preferable for the use in implantable ophthalmic lenses and hard contact lenses [2]
PMMA is used in gate dielectric [3], and various biomedical devices including eye glasses, drug delivery agent, facial prosthesis, artificial bone, jaw implants, nasal stents and others [4]

Summary

Introduction

Polymethyl methacrylate (PMMA) has attracted more and more attention in various industrial applications due to its low cost, ease of processing, excellent physical and chemical properties [1]. Its light transmittance is similar to glass, its mechanical properties such as rigidity and low density make PMMA more preferable for the use in implantable ophthalmic lenses and hard contact lenses [2]. Despite the excellent PMMA bulk properties, its surface inherited hydrophobic nature limits its compatibility when it is used as implant bio-material. The poor interfacial adhesion between the PMMA optical cylinder and the donor corneal tissue can produce various medical problems. Perpetual blinking and eyeball movement can exacerbate corneal tissue, causing the PMMA cylinder to become loose, providing an opportunity for the invasion of bacteria and inflammatory cells [6]

Methods

Results

Conclusion