Patent ID: 7038006

Claim:
A polyamide obtained by polycondensation of a diamine component containing 2-methyl-1,5-pentanediamine and a dicarboxylic acid component containing azelaic acid, wherein the diamine component contains at least 70 mol % of 2-methyl-1,5-pentanediamine and the dicarboxylic acid component contains at least 70 mol % of azelaic acid and the polyamide is obtained by polycondensation of only the diamine component and the dicarboxylic acid component, comprising the following properties of (1) to (4), (1) when a stretched film is polarized in an electric field of 200 MV/m, a remanent polarization is at least 30 mC/m 2 , (2) the relative viscosity of a 1 g/dl solution of the polyamide in 96% concentrated sulfuric acid at 25° C. is 1.3 to 5.0, (3) the glass transition temperature, measured with a differential scanning calorimeter, of the polyamide is 80° C. or less and a calorific value at a cooling crystallization exotherm peak is 5J/g or less, and (4) the polyamide is soluble in an amount of at least 5 mass % at 25° C. in at least one member selected from the group consisting of methanol, ethanol and 2-propanol.