The polycarbonate film (PC) surface was treated using glow discharge low-pressure air plasma. The modified surface was characterized by contact angle, FTIR, XRD, AFM, and XPS analysis. The surface-modified samples were further investigated using T-peel test for technical applications. The surface energy of the sample was estimated by measuring contact angle. The results show that, after plasma treatment, the root mean square (RMS) roughness of PC film was gradually increased with exposure time. Plasma treatment modified the chemical composition of the polymer surface and it made the surface to be highly hydrophilic. It was found that the air plasma treatment increases the polar component of PC film. 1. Introduction Polymers are generally macromolecules formed by the repeated linking of large number of small molecules. Polymers are widely used in automobile, defense, electrical, and computer components and so forth [1]. Nowadays organic polymers are usually replaced by traditional engineering material such as metals, glasses, and ceramics because of their good characteristic features in physical and chemical aspects [2]. The low-surface energy of polycarbonate results in poor adhesion of additional coatings, which leads the manufacturers to face more technical challenges [3]. Because of their superior performance and low-cost the polymer-based materials are used in many areas. To modify polymer surfaces low temperature, low-pressure plasma is commonly used [4]. In modern days, various methodologies were developed to convert polymer surface for enhanced wettability, adhesion, and so forth, [5]. To modify the surface properties of polymers, low-pressure cold plasma treatment is commonly used as a dry process. The effect of plasma treatment depends on internal and external parameters like type of plasma (DC, RF, or microwave), the discharge power density, pressure, and flow rate of the gas or gas mixture and exposure time [6]. The surface of the polymer is activated during plasma treatment, which brings about the chain session of the existing groups on the surface of the polymer and creates new functional groups such as –OH and –OOH [7, 8]. Air plasma is used to increase polar functional groups (hydroxyl, carboxyl, ether, carbonyl, etc.) which can successfully increase the surface free energy of the polymer [9]. In the recent years the surface treatment of PC was performed by many researchers to make suitable polymer surfaces for adhesion [10]. In this work PC films were treated with DC glow discharge air plasma under different exposure times with an
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