Synthesis of inorganic-organic hybrid membranes consisting of organotrisiloxane linkages and their fuel cell properties at intermediate temperatures

Inorganic-organic hybrid membranes consisting of an aliphatic main-chain polymer and trisiloxane bond were synthesized using a simple, one-pot process from a trisiloxane derivative, phosphonic acid acrylate, and vinylbenzotriazole. 1,5-Divinyl-3-phenylpentamethyltrisiloxane )DPPMTS) was copolymerized with 2-hydroxyethyl methacrylate acid phosphate)HEMAP), and N-vinylbenzotriazole)VBT), yielding inorganic-organic hybrid composites. The formation of the inorganic-organic hybrid structure was confirmed by IR, C-13, and Si-29 NMR spectroscopy. The membranes exhibited good thermal stabilities up to 200 degrees C. The aliphatic chains of the methacrylate derivative copolymerized with trisiloxane in the hybrid membranes improved the mechanical properties of the membranes. The tensile modulus of the VBT/HEMAP/DPPMTS membrane with a composition of 1:9:5 was 1.19 GPa. The conductivities of the 1:9:5 membranes were 5.3 x 10(-2) S cm-1 and 4.1 x 10(-4) S cm(-1) at 100 and 19.3% relative humidity)RH), respectively, and 130 degrees C. The membrane electrode assembly)MEA) using the hybrid membrane exhibited a peak power of 7.8 mW cm(-2) at 140 degrees C and 30% RH.(C) 2017 Elsevier Ltd. All rights reserved.