| 摘要 |
The invention provides a piezoelectric polymer material comprising a helical chiral polymer having a weight average molecular weight of from 50,000 to 1,000,000 and optical activity, the piezoelectric polymer material having: crystallinity as obtained by a DSC method of from 40% to 80%; a transmission haze with respect to visible light of from 0.0% to 40%; a standardized molecular orientation MORc, which is measured with a microwave transmission-type molecular orientation meter at a reference thickness of 50 µm, of from 3.5 to 15.0; and a product of the crystallinity and the standardized molecular orientation MORc of from 100 to 700, and a piezoelectric polymer material comprising a polylactic acid-based polymer and polyvinylidene fluoride, wherein a content of the polyvinylidene fluoride is from more than 0 mass% to 5 mass% with respect to the total mass of the polylactic acid-based polymer, and wherein a piezoelectric constant d 14 measured by a resonance method at 25°C is 10 pC/N or more. According to the invention, a method of producing a piezoelectric polymer material that exhibits a large piezoelectric constant d 14 and excellent transparency and dimensional stability. |
