Effect of Molecular Weight on the Application of Sulfonated Poly(arylene ether) Polymers for Proton Exchange Membrane Fuel Cells

• Main Authors: Chin-huai Teng, 鄧勤懷
• Other Authors: Wen-yao Huang
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/5bhg96

碩士 === 國立中山大學 === 光電工程學系研究所 === 106 === This thesis is mainly a continuation of the previous laboratory research( SA7 series, SA8 series, SA9 series), selected SA8 as the material for this study, by controlling the reaction time and the amount of solvent to polymerize into the appropriate molecular weight, and study the influence of the difference in molecular weight on the characteristics of the film. Discussed the microphase separation pattern under different molecular weight conditions and the effect of efficiency after assembly into fuel cell components. The structures of materials were confirmd by FT-IR, 1H -NMR, and mass.The molecular weights of different polymers were measured by GPC, ranging from 65,000 to 180,000 g/mol.The polymers show thermal degradation temperatures are higher than 510oC. Three sulfonated polymers show thermal degradation temperatures are higher than 252oC. The IEC values between 2.4 to 3.2 mmol/g. At 80oC, except SA8-3.2, the film still retains its full morphology, its water uptake is ranging from 86% to 157%, and it has good dimensional stability (17%~44%) and mechanical properties (0.29~0.46GPa). The proton conductivity is up to 225 mS/cm and much more better than Nafion 211 (151 mS/cm). Through the viscosity, TEM and DLS, this series of sulfonated polymers has a good micro-phase separation pattern. The final component efficiency section, in which SA8-3.2''s element efficiency is as high as 1.3 W/cm2, is almost the same as that of the Nafion 211. In summary, changing the molecular weight of the SA8 material will affect the micro-phase separation pattern of the film, which will result in a higher molecular weight of material has higher element efficiency.