Properties Study And Synthesis Of P(VDF-co-CTFE)-g-pssa Proton Exchange Membrane By ATRP

In nowadays, our environment pollution and energy crisis increased seriously. Many scientific researchers pay more attention to PEMFC(Proton exchange membrane fuel cell) due to it’s advantages of long working life, low noise, high power density and no pollution to enviroment. With the proton conduction ability of proton exchange membrane, it plays an important role which can change the fuel cell’s property in PEMFC. The common business PEM is Nafion, it is a sulfonated tetrafluoroethylene-based polymerdeveloped by Dupont company.Nafion membrane has high proton conductivity and excellent thermal and mechanical stability, but the drawback of high cost and complex production process limit it’s development in fuel cell. So it is necessary to develop a new type materials of PEM to replace the Nafion’s position.In this paper, we used ATRP method to graft styrene to polyvinylidene difluoride-co-chlorotrifluoroethylene(PVDF-co-CTFE) backbone then sulfonated the graft polystrene side chains with different reaction time. Their characteristics have been tested by FTIR,TGA,EIS and so on. The influences between temperature and humidity in water/air can change the proton conductivity, the date shows it can be used in the PEMFC.At this experiment, the best reaction condition has been found by change reaction temperature, reaction time, the kind of ligand and analyzed the experiment’s complexity.The membranes are prepared by solution casting, We find the shape change and water uptake changed with the degree of sulfonation. When the side chain’s length is 25, the properties of membrane descent a lot. So we composite the properties of membrane and proton conductivity find that the suitable graft length is 12 and the degree of sulfonation is 100%. This membrane has an excellent proton conductivity(1.2×10-2S/cm), lower water uptake(30%) and good mechanical property(23MPa). It can be used in proton exchange membrane and Fuel cells.