Thesis Type: Postgraduate
Institution Of The Thesis: Gazi University, Fen Bilimleri Enstitüsü, Turkey
Approval Date: 2010
Thesis Language: Turkish
Student: Nagihan DEMİRCİ
Supervisor: NURSEL DİLSİZ
Abstract:Polymers have been frequently used in manufacture of medical devices. Poly(vinyl chloride) (PVC) which is used in production of catheter have a hydrophobic characteristic. During the usage of catheter to prevent to form of trauma and infection in ureatra, catheter should to be coated with a hydrophilic polymer and have lubrious effect when contact with water. These surfaces are preferred to have anti-microbial properties too. In this study, PVC surface modified with plasma using N-vinyl-2- pyrolidone, allylamine and N,N-dimethylacrylamide monomers which have hydrophilic characters. Coated surfaces were dipped solution of poly(vinyl pyrollidone) and the effect of plasma treatment time on slippery and drying time was investigated. In addition, according to be used to cover of catheter surfaces, studies of synthesis of a new hydrogel were done. Chitosan which is a natural polymer and have a anti-microbial characteristic was used to synthesize hydrogel. Hydrophilic characteristics, chemical structure characteristics, thermal characteristics and surface morphology of samples were investigated with in turn in order contact angle measurements, surface energy calculations, FTIR spectroscopy, Thermogravimetric Analysis (TGA) and Differential Thermogravimetric Analysis (DTGA), Atomic Force Microscopy (AFM). In addition, swelling kinetics of hydrogels were investigated. It was observed when contact angle of original PVC was 116.4° after plasma treatment this value decreased at about 0°. So hydrophilic characteristic was gained at PVC surfaces. Slippery and drying time of catheters after dipping at PVP solution were increased with dependent on hydrophilic characteristics. It was seen with AFM , when surface roughness of samples increased after plasma treatment, surface of samples were smooth after solution of PVP coating. Catheters were coated with poly(vinyl alcohol)/chitosan hydrogel which showed most hydrophilic and swelling degree. It was observed that slippery of coated surface and surface adhesion of coating were good. Consequently, for having both hydrophilic and anti-microbial characteristics of PVC catheters, the method which was used beforehand was developed and a new method was attempted and it was exposed that this method was available.