11745

10777

كارشناسي ارشد

پليمر

اصفهان: دانشگاه صنعتي اصفهان: دانشكده مهندسي شيمي

1395

دوازده،[89]ص.: مصور،جدول،نمودار

ص.ع.به فارسي و انگليسي

طيبه بهزاد

لاله قاسمي مباركه، عليرضا علافچيان

روح اله باقري، حسين توانايي

1395/08/19

كتابنامه

مهندسي شيمي

ID10777

Preparation and Characterization of Electrospun Poly caprolactone Nanofibers and Investigation of Cellulosic Microfibrils Addition on Hydrophobicity and Degradation Rate of Nanofibers Mohsen Zolfagharlou Kohi Mohsenzk65@gmail com Department of Chemical Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language PersianAbstractPoly caprolactone is a biocompatible and biodegradable synthetic polymer that hasmany potential applications in tissue engineering specially medical scaffollds Degradationrate of this polyester due to its semicrystalline nature is slower than other biodegradablepolymers such as polyglycolideacid PGA polylactide PDLA and their copolymers Therefore this polymer can be only used for long term usually more than one year medical applications In addition this polymer has hydrophobic nature that limited itsapplications in tissue engineering and medical Due to its low melting point goodcompatibility with other polymers and nanoparticles there have been some efforts byresearchers to modify the properties of this polymer The main objective of this research ismodification of electrospun poly caprolactone fibers using cellulose microfibrilsextracted from rice husk Initially a chemo mechanical method was applied to extractmicrofibrils from rice husk Chemical methods used to extract microfibrils includeswelling acidic and alkaline hydrolysis and then bleaching of rice husk fibers Subsequently the obtained microfibers were converted to microfibrils by applyingmechanical treatment via passing bleached fibers through supergrinder three times Theextracted rice husk microfibrils were characterized by different methods The chemicalcomposition analysis of fibers showed successful removing of non cellulosic materialsfrom fibers structure Using high performance liquid chromatography HPLC test it wasfound that cellulose content was changed from 34 67 percent for raw materials to 94 30percent for bleached fibers In addition Fourier transform infrared spectroscopy FTIR showed the successful removal of functional groups related to non cellulosic materials The scanning electron microscopy SEM was applied for morphological evaluating ofraw acidic and alkaline treated and bleached fibers Also Field Emission ScanningElectron Microscopy FE SEM showed successful converting of microfibers tomicrofibrils by applying supergrinder mechanical method By using image analysissoftware the average diameter of prepared microfibrils was determined to be less than 20nanometers Also the degree of crystallinity of nanofibers was achieved to be about 76 2percent by employing X ray diffraction analysis After characterizing of cellulose

طيبه بهزاد

لاله قاسمي مباركه، عليرضا علافچيان

روح اله باقري، حسين توانايي