| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a separator seal for a polymer electrolyte fuel cell that is excellent in moldability, particularly injection moldability, has low permanent compression set of cured rubber, and is also excellent in sealing property. <P>SOLUTION: Constituted is the sealing material for separator of polymer electrolyte fuel cell including: (A) a liquid polyorganosiloxane having at least two alkenyl groups bonding to silicone atoms in the molecule and a weight-average molecular weight of <100,000; (B) crude rubber-like polyorganosiloxane having a weight-average molecular weight of ≥150,000; (C) an organo-hydrogenpolysiloxane having at least three hydrogen atoms bonding to silicone atoms in a molecule; (D) a fumed silica having 50 to 400 m<SP>2</SP>/g of specific surface area by BET method; and (E) a catalyst for addition reaction, as the essential components, wherein its viscosity ranges from 20 to 200 Pa s upon a shearing velocity of 10 s<SP>-1</SP>at 25°C. As a result, the separator seal for a polymer electrolyte fuel cell that is excellent in moldability, particularly injection moldability, has low permanent compression set of cured rubber, and is also excellent in sealing property can be constituted. <P>COPYRIGHT: (C)2009,JPO&INPIT |
