Abstract
Generally most plastic materials are intrinsically hydrophobic, low surface energy materials, and thus do not adhere well to other substances. Surface treatment of polymers by discharge plasmas is of great and increasing industrial application because it can uniformly modify the surface of sample without changing the material bulk properties and is environmentally friendly. The plasma processes that can be conducted under ambient pressure and temperature conditions have attracted special attention because of their easy implementation in industrial processing. Present work deals with surface modification of polycarbonate (PC) by a dielectric barrier discharge (DBD) at atmospheric pressure. The treatment was performed in a parallel plate reactor driven by a 60Hz power supply. The DBD plasmas at atmospheric pressure were generated in air and nitrogen. Material characterization was carried out by contact angle measurements, and X-ray photoelectron spectroscopy (XPS). The surface energy of the polymer surface was calculated from contact angle data by Owens-Wendt method using distilled water and diiodomethane as test liquids. The plasma-induced chemical modifications are associated with incorporation of polar oxygen and nitrogen containing groups on the polymer surface. Due to these surface modifications the DBD-treated polymers become more hydrophilic. Aging behavior of the treated samples revealed that the polymer surfaces were prone to hydrophobic recovery although they did not completely recover their original wetting properties.
Highlights
Polymers are frequently applied in modern industry owing to their high performance, relatively low cost and easy recycling
The dielectric barrier discharge (DBD) discharge used for PC treatment operates in filamentary mode i.e. it is constituted by many tiny streamers distributed over entire area of the dielectric barrier
In case of filamentary DBD driven by a sinusoidal power source the typical shape of its Q-V curve is a parallelogram [6]
Summary
Polymers are frequently applied in modern industry owing to their high performance, relatively low cost and easy recycling. To enhance the surface energy of polymers, their surface should be activated by some kind of chemical or plasma treatment [3]. The chemical effect of plasma treatment consists of reactions between the plasma species and polymer surface can form different polar groups, such as, -OH, C-O, C-OH, C=O etc.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have