| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an electromechanical transducer containing a dielectric elastomer having a high electric resistance together with a high breakdown field strength, for the purpose of giving further higher efficiency to the transducer. <P>SOLUTION: The dielectric elastomer contains polyurethane polymer with reaction product from polyisocyanate (A), and/or polyisocyanate prepolymer (B), and a compound (C) having at least two isocyanate reactive groups. The compounds (B) and/or (C) contain poly tetramethylene glycol ether unit represented by formula (I)-[O-CH<SB>2</SB>-CH<SB>2</SB>-CH<SB>2</SB>-CH<SB>2</SB>-]<SB>n</SB>, where the n in formula (I) is a number specified by an inequality n≥25, and a maximum n<SB>max</SB>and a minimum n<SB>min</SB>are selected so that a difference between the maximum n<SB>max</SB>and minimum n<SB>min</SB>is a number in the range from 0 through 4. Values of n, n<SB>min</SB>, and n<SB>max</SB>may be the same or the different numbers. The compounds (B) and (C) does not contain the poly tetramethylene glycol ether unit except the poly tetramethylene glycol ether unit represented by formula (I). <P>COPYRIGHT: (C)2011,JPO&INPIT |
