تهيه و شناسايي ﴿3،4- اتيلن دي اكسي تيوفن متين﴾ ها، پلي كاپرولاكتون و نشاسته-پيوند شده-پلي كاپرولاكتون با استفاده از مايعات يوني

چكيده انگليسي :

Synthesis and characterization ofPoly 3 4 ethylendioxythiophene methine s Polycaprolactone and Starch Grafted Polycaprolactone by Using of Ionic Liquids Zahra Mohamadi z mohamadi@ch iut ac ir February 26 2012 Department of Chemistry Isfahan University of Technology Isfahan 84156 83111 I R Iran Degree M Sc Language FarsiDr A Abdolmaleki Email abdolmaleki@cc iut ac ir amirabdolmaleki@yahoo comAbstract The ionic liquids due to their remarkable properties like nonflammable high thermal negligible vaporpressure Low toxicity and their simple reusability have been widely used as solvent or catalyst inpolymerization reactions or industrial technologies So in this project four ionic liquids were prepared andcharacterized by 1H NMR and FT IR spectra They were used for synthesizing of conjugated polymers andbiodegradable polymers In the first part of the project the Poly 3 4 ethylenedioxythiophene methine s wereprepared by the acid catalyzed polymerization of the 3 4 ethylenedioxy thiophene and aldehydes in thepresence of the acidic ionic liquids N methyl 2 pyrrolidonum hydrogensulfate NMP H HSO4 andMorpholinium hydrogensulfate Mor H HSO4 The resulting polymers were obtained in good yields withinherent viscosities ranging between 0 04 and 0 1 dl g These polymers were readily soluble in commonorganic solvents such as DMF NMP CH2Cl2 p dioxane chloroform and etc The molecular weights Mw Mn for PEDOT MB and PEDOT NB were 5367 4626 and 8486 7411 respectively corresponded tomolecular weight distributions Mw Mn were rather narrow 1 16 and 1 14 respectively The polymerstructures were confirmed and studied by FT IR 1H NMR spectra and also elemental and thermo gravimetricanalysis techniques The polymers obtained were highly colored because of dehydrogenation The degree ofdehydrogenation was estimated by the 1H NMR results The thermal gravimetric analysis showed that thepolymers had a fairly good thermal stability The optical and electrochemical band gap of the conjugatedpolymers was measured by cyclic voltammetry and UV Vis spectra The polymer conductivity was tested byEIS studies using K3Fe CN 6 K4Fe CN 6 as a redox probe to evaluate the electron transfer kinetics of theelectrodes The charge transfer resistances of the reactions at electrodes were compared to the doped andundoped electrodes Regarding to the obtained results from Nyquist diagram it was found that electrodescharge transfer resistance was decreased in doping state and it was closed to the bare carbon paste electrode In the second part the biodegradable polycaprolactone was prepared by ring opening polymerization in thepresence of the ionic liquids The resulting polymer exhibited good yield and inherent viscosity was 0 12dl g The obtained polymer chemical structure was verified by the 1H NMR and FT IR spectra In thefollowing this polymer was used to improve quality level mechanical properties and hydrophilic propertyreduction of the starch so the ring opening polymerization of the caprolactone in the presence of the starchhydroxyl groups as an initiator and ionic liquid as a catalyst was done The obtained starch grafted polycaprolactone verified by 1 H NMR and FT IR spectra The resulting polymer exhibited inherent viscositywas 0 24 dl g The Scanning Electron Microscopy images of the starch and St g PCL copolymer to the verygood interfacial adhesion between the starch and the PCL chains The surfaces of the starch granules lookedsmooth whereas the surfaces of St g PCL exhibited roughness and polygonal appearance and someconnections between granules could be also seen clearly Therefore it obviously showed that the PCL waslocated on the surfaces of the starch granules which will be helpful to the improvement of the mechanicalproperties of the modified composites Keyword Ionic liquids Low band gap Conjugated polymers Electrochemistry Poly 3 4 ethylenedioxythiophenemethine s Biodegradability Caprolactone starch g polycaprolatone

محمدي، زهرا

تهيه و شناسايي ﴿3،4- اتيلن دي اكسي تيوفن متين﴾ ها، پلي كاپرولاكتون و نشاسته-پيوند شده-پلي كاپرولاكتون با استفاده از مايعات يوني

باند گپ , پليمرهاي مزدوج , زيست تخريب پذيري