الفهرس 
THEORETICAL PARTOnly 14 pages are availabe for public view
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Abstract
Nanofibers are a new class of material with unique features and a wide scope of uses. This research article studies the preparation of a novel polymer nanofiber composite from polyvinyl alcohol (PVA) (10%) blended with carboxymethyl cellulose (CMC) (2.5%) with different doses of Poly Ethylene Glycol (PEG) (0.25, 0.5, 0.75 g). Four different samples of PEG0, PEG1, PEG2 and PEG3 were prepared (6.25,7.5, 8.75 and 10 total % (w/v) respectively and fully characterized using SEM, TEM, FTIR and TGA analysis. The SEM analysis was used to observe the morphology and the average diameter of the electrospun fibers also to help in optimizing the PEG concentration and the electrospinning condition (needle-to-collector distance, voltage, and flow rate), that can be used for the preparation of nanofiber membrane composed of PVA/CMC/PEG. The results showed that the nanofiber morphology and diameters of the nanofibers (PEG1, PEG2 and PEG3) were enhanced and the beads disappeared with increasing the PEG concentration and the optimum values for the electrospinning parameters to obtain PEG3 nanofibers with less average diameter are flow rate of 1ml/h, Voltage of 25 kV and Needle-to-collector distance of 25 cm with average diameter of electrospun nanofibers 362 nm. The Water contact angle (WCA) to assess the water absorption and swelling properties of the membrane were take place and found to be 45.35. This value was evidence that the membrane had hydrophilic properties. Treatment of the PEG3 with cross linking physically was taking place using using citric acid as a vapor cross linking agent. The water uptake was studied and found to be 20 %, this indicated that the membrane did not absorb large amount of water which helps it be used in waste water applications. After Treatment with crosslinking the membrane was used for separating oil from water (O/W) emulsion and found that the highest COD removal is (10.67 g/L) for the Lubricant oil and the highest percentage of reduction in COD (81.47%) is obtained for the paraffin oil.