الفهرس 
Theoretical BackgroundOnly 14 pages are availabe for public view
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Abstract
Plasma is a partly ionised gas that is formed of ions, neutrals, and charged particles. It is regarded to be the 4th state of matter. Plasmas are capable of conducting electric currents and producing magnetic fields. When energy is coupled to a gaseous medium in order to form plasma, a temperature and pressure are applied across the medium in order to generate the plasma. This is the common principle that is used to generate plasma. Plasma can be produced either naturally, as in the case of stars and lightning, or artificially, like in fluorescent and neon lights, plasma televisions, and other similar electronic devices. Non-thermal plasma and thermal plasma are two distinct types of plasma, based on the mechanism employed to generate the plasma. There are many different types of gas discharges, and they are categorized according to frequency as follows: alternating current (ac) discharge, direct current (dc) discharge, microwave discharge, radio frequency discharge, pulsed glow discharge, and dielectric barrier discharge. Some of the topics that are discussed in this thesis include how to convert a microwave oven into a plasma reactor. A microwave oven-based plasma generation process is disclosed that is both easy and low-cost. Polyvinyl alcohol (PVA) polymer’s excellent properties, it can be used in many fields, including food packaging and agriculture, after plasma treatment. A solution-casting approach was used to create pure polyvinyl alcohol (PVA) film, and Oxygen plasma treatment was used to modify the PVA surface at a constant power of 1000W with different O2 flow rates and pressures. XRD, ATR-FTIR, SEM, AFM, contact angle, work of adhesion, XPS, and UV-vis spectra were used to examine PVA films’ surface properties. An X-ray study revealed that pure PVA film is semicrystalline and increases its amorphous nature after oxygen plasma treatment. However, there is no discernible difference in the structure of plasma treated PVA films when compared to untreated PVA films. The transmission of PVA film using ATR FTIR is measured by varying oxygen flow rate, pressure, and treatment time. The transmission peaks of the oxygen treated PVA film are more intense at 15 sec, 26 mbar, and 6 L/min. At 26 mbar which are the optimal parameters that will be used in all the following results. A slight peak shift towards higher wavenumbers is observed, corresponding to the C-O stretching of acetyl groups by ATR-FTIR measurement. After plasma treatment, it was discovered that the contact angle had decreased from 39º ± 0.4 to 20.8º ±0.2, in addition, the work adhesion is increased from 128.2 mN/m to 140 mN/m after oxygen plasma treatment.it suggests that the PVA film surface is modified to a hydrophilic due to an increase in roughness and the introduction of oxygen. This is demonstrated by measurements carried out with an AFM, as well as by the fact that the oxygen treatment led to an increase in wettability. The results of XPS confirm that the material is hydrophilic. Under the same settings that were optimized for the ATR-FTIR. The UV region has the highest transmittance at nearly 64%, and the visible region has 85.55% of the UV-vis spectrum. Because of these findings, PVA became a transparent material. All these steps show that oxygen plasma treatment changes the ”hydrophilicity, wettability, adhesion, and transmission” properties of PVA film so that it can be used in greenhouses, food packaging, and coating.