Thesis (Ph.D.) - Cairo University - Faculty of Science - Department of Biophysics

In this work, Polyethylene terephthalate films were divided into three groups, each group was exposed to a type of radiation.The first group was exposed to microwave with different powers (180, 360, 540 and 720 W).The second one exposed to UV with wavelengths (254 and 365 nm). The third group exposed to ND-YAG laser (1.046 om) radiation with powers (0.3, 3 and 6 W).There was another group of new blends based on PET (polyethylene terephthalate) and chamomile oil with different concentrations (50, 100 and 200 oL). All the samples were studied through dielectric measurements, ATRFTIR (Attenuated total reflection- fourier transform infrared) and contact angle measurements. Monitoring of the platelets adhesion on the surface of the samples was carried out by SEM (Scanning electron microscope) using platelets rich plasma method. The anticoagulant properties of the films were studied through PT (Prothrombin time), PTT (partial thromboplastin time) and INR (International normalized ratio) measurements. In addition, hematological studies were carried out on the blood samples that contact the treated samples. The results were discussed and compared with each other to find out the best properties suitable for use in blood contact applications. Results revealed that all the tested techniques increased the hydrophilicity of the PET as evaluated by the decreasing of contact angle values (78.90{u00BA}) for the un-irradiated PET. The super hydrophilic PET films obtained by irradiation the samples with 0.3W Nd:YAG 1.046 om laser and the lowest reading of contact angle 45.85o is found at 0.3 W. Microwave irradiation with power does not exceed 360 W regarded as a new, safe and cheap strategy for surface modification for PET. Incorporation of chamomile oil up to 100 oL into PET matrix is promising methods for PET modification as it enhances the wettability of the polymer and keeping the bulk of the polymer intake

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