سنتز غشاء پيل سوختي پليمري بر پايه پلي ايميدهاي سولفونه و مطالعه اثر ذرات سيليكا بر عملكرد آن

چكيده انگليسي :

Synthesis Sulfonated Polyimide for Polymer Electrolyte Membrane Fuel Cell and Study of the Effect of Nano Silica on its Performance Mohammad Jalil Namazi Fard mj namazifard@ce iut ac ir Date of Submission 2012 03 11 Department of Chemical Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language FarsiSupervisor Morteza sadeghi m sadeghi@cc iut ac ir Shadpour Mallakpour mallak@cc iut ac irAbstract The global supply of energy is highly dependent on fossil fuels and gives rise to global warming due to theemission of greenhouse gases such as carbon dioxide Fuel cells are emerging technologies for clean powergeneration in place of the combustion of fossil fuels Particularly polymer electrolyte membrane fuel cells PEMFCs can be used as alternatives to internal combustion engines in vehicles as well as power supplies instationary and portable applications Furthermore for PEMFC based applications to achieve commercial success the membrane must be capable of performing well under increasingly stringent operating conditions e g hightemperature low relative humidity Even Nafion currently the most widely used membrane does notsatisfactorily meet all of these criteria Sulfonated polyimides SPI have been considered as promisingalternative for Nafion Sulfonated polyimide has good properties but suffers from hydrolytic stability Researchers have suggested different routes to increase hydrolytic stability of polyimide Using aliphatic moetiesin polymer structure is one of important route to increase hydrolytic stabilityin polyimide In this project threekind of aliphatic ether diamine like 1 13 diamno 4 7 10 trioxatridecane TOTD 4 9 dioxa 1 12 dodecanediamine DODD and 1 8 diamino 3 6 dioxaoctane DOO be used Also 3 3 4 4 benzophenonetetracarboxylicdianhydride BTDA and 4 4 oxydianiline ODA as fully aromatic dianhydride and diamine has been used Post sulfonation was applied for sulfonation of polyimide At first step polyamic acid prepared from diamine anddianhydride and then Polyamic acid treated with concentrated sulfuric acid for two hours for carring out post sulfonation method Then sulfonated polyimide membrane was prepared by thermal imidization of casted film This project based on two parts At the first of the project four membranes prepared Because two of themembranes were broken The characteristic parameters of the membranes were not measured Fully aromatic SPImembrane and SPI membrane contain 20 DOO diamine successfully prepared and characterized Water uptakeresult showed that both membranes could absorb 5 4 water while is lower than Nafion But average number ofwater molecules per sulfonic acid group is higher than Nafion Hydrolytic stability for SPI contains 20 molealiphatic ether moiety was measured about 60 hours and it was 48 hours for fully aromatic structure Ionexchange capacity IEC for fully aromatic structure was 0 379 equiv gram and it was higher than SPIcontain 20 mole aliphatic ether moieties but both of them have lower IEC than Nafion Proton conductivityincreased from 1 5 10 3 mZ cm for SPI contain 20 mole aliphatic ether moieties to 2 10 3 for fullyaromatic SPI measured proton conductivity for Nafion was 10 4 So both synthesis membranes had higherconductivity than Nafion At second part of project nanocomposite membrane prepared by addition nano silica tofully aromatic SPI at various weight percentage Micrograph photo observation indicated phase separationbetween Ionic and non Ionic sequence IEC for nanocomposite membranes contain 2 4 and 8 wt wasrespectively 0 316 0 242 and 0 081 and proton conductivity was 10 2 2 2 10 3 and 6 1 10 2 Protonconductivity of nanocomposite membrane was higher than pristine SPI and Nafion Maximum measured wateruptake was 11 for nanocomposite membranes contain 4 wt nano silica Generally addition nano silica tosulfonated polyimide increased water uptake and than pristine SPI Keyword sulfonated polyimide post sulfonation aliphatic ethric diamine sulfonatedpolyimide n

نمازي فرد، محمد جليل

سنتز غشاء پيل سوختي پليمري بر پايه پلي ايميدهاي سولفونه و مطالعه اثر ذرات سيليكا بر عملكرد آن

پساسولفوناسيون , دي آمين آليفاتيك -اتري , ايميدازسيون گرمايي