Preparation And Properties Of Inorganic Composite And N Heterocyclic Ring For Proton Exchange Membrane Material

Proton exchange polymer membrane materials,as the"heart"of the proton exchange polymer membrane material fuel cell,deserve better attention and research to promote the development of fuel cell.Currently,Nafion polymer membrane material has been commercialized,but there are still many deficiencies.The polymer membrane material of sulfonated poly aryl ether has excellent mechanical properties,thermal properties and high proton conductivity.It is one of the most promising polymer membrane materials.However,with the evaporation loss of water at high temperature,its proton conductivity has declined rapidly,still unable to meet the requirements of fuel cell.Therefore,it is imperative to modify the polymer membrane material of sulfonated aromatic proton exchange.Therefore,in this paper,two kinds of new sulfonated poly?aromatic?proton exchange polymer membrane materials were prepared and studied.First,organic-inorganic composite proton exchange polymeric membrane materials were preparedbased on sulfonated poly aryl arylene ether ketone?SPAEK?.As a kind of sulfonated aromatic polymer,sulfonated poly aryl arylene ether ketone polymer has the advantages of high thermal stability,good mechanical property,good chemical stability and low cost.Amino propyl functionalized mesoporous silica nanoparticles?NH₂-SiO₂?were doped into the polymer matrix as inorganic particles,and the organic-inorganic compound proton exchange polymer membrane materials were prepared.NH₂-SiO₂ has the unique advantages of inorganic particles,the larger specific surface area can strengthen water retention of polymer membrane materials,make the polymer membrane materials in high temperature conditions can still have high proton conductivity;At the same time,the amino and sulfonic acid groups also have the interaction of acid-base ions,so that the polymer film materials can maintain certain mechanical properties and dimensional stability.The SPAEK/NH₂-SiO₂-7%membrane at 80?is a prominent water retention(water stripping coefficient is 1.37×10^-10 cm²/s);The SPAEK/NH₂-SiO₂-5%membrane possessed satisfactory a proton conductivity of 0.159 S cm^-1 at 100°C,which was larger than that of SPAEK(0.0413 S cm^-1).Secondly,in order to further improve the comprehensive properties of sulfonated poly aryl ether ketone polymer membrane materials,it is intended to directly modify the polymer chain to improve the proton conductivity.The nitrogen heterocyclic structure was introduced by sulfonated poly aryl ether ketone,and the proton exchange polymer membrane material containing the nitrogen heterocyclic ring was prepared.Imidazole,as a kind of N heterocyclic ring,can act as the donor and donor of the proton,and improve the proton conductivity of the polymer membrane material in the case of high and low humidity.The proton conductivity of SPI-3 was 0.109 S cm^-1 above Am-SPAEK-2.At the same time,it shows excellent mechanical properties and oxidation stability.