Local piezoelectric response, structural and dynamic properties of ferroelectric copolymers of vinylidene fluoride–tetrafluoroethylene
- 162 Downloads
The characteristics of the local piezoelectric response of isotropic films of copolymers of vinylidene fluoride (VDF) were compared with 6 and 29 mol% tetrafluoroethylene (TFE) obtained by crystallization from a solution in acetone. Time dependence of the electric displacement response was analyzed after switching of the spontaneous polarization. A copolymer with a higher content of tetrafluoroethylene is characterized by higher values of electrical displacement and piezoelectric response. For interpretation of this fact, we used molecular mobility in amorphous phase dates. It is shown that the activation energy of local and cooperative liquid-like (in the amorphous phase) mobility is markedly lower in the copolymer with a higher content of TFE. Under identical conditions of the crystallization, both films of the copolymers lead to the formation of larger crystals of the polar phase and magnitude of a “long” period at a high content of copolymer of TFE. It is postulated that these structural parameters are responsible for the stable value of residual local piezoelectric activity. It is found that the rapid decay of the signal in the local piezoresponse of polarized films is controlled by the activation energy of the local and cooperative dynamics chains of the amorphous phase.
KeywordsFerroelectric polymers Structure Polarization Piezoelectricity Molecular mobility
The work was carried out with financial support in part from the Ministry of Education and Science of the Russian Federation in the framework of Increase Competitiveness Program of MISiS, RFBR research project no. 14-03-00623 A. The studies are performed on the equipment at the “Materials Science and Metallurgy” Shared Facilities Center of the National University of Science and Technology “MISiS” (ID project RFMEFI59414X0007, contract no. 14.594.21.0007).
- 11.Kochervinskii VV, Glukhov VA, Sokolov VG, Romadin VF, Murasheva EM, Ovchinnikov YK, Trofimov NA, Lokshin BV (1998) Vysokomol Soedin A 30:1969Google Scholar
- 12.Kochervinskii VV, Murasheva EM (1991) Vysokomol Soedin A 33:2096–2105Google Scholar
- 13.Kochervinskii VV, Chubunova EV, Lebedinskii YY, Shmakova NA, Khnykov AY (2011) Polymer Science Ser. A 53:929–946Google Scholar
- 15.Munoz RC, Vidal G, Mulsow M, Lisoni JG, Arenas C, Concha A (2000) Phys. Rev. B 62:4686–4697Google Scholar
- 20.Kochervinskii VV, Malyshkina IA, Pavlov AS, Bessonova NP, Korlyukov AA, Volkov VV, Kozlova NV, Shmakova NA. J Polym Sci Polym Phys In pressGoogle Scholar
- 21.Lovinger AJ, Davis DD, Cais RE, Kometani JM (1988) Macromolecules 21: 78Google Scholar
- 23.Collins L, Kilpatrick JI, Viassiouk IV, Tselev A, Weber SAL, Jesse S, Kalinun SV, Rodriguez BJ (2014) Appl Phys Letts 104:133103, 1–5Google Scholar
- 24.Murari NM, Hong S, Lee HN, Katiyar S (2011) Appl Phys Letts 99:052904, 1–3Google Scholar
- 25.Kochervinskii VV, Kiselev DA, Malinkovich MD, Pavlov AS, Kozlova NV, Shmakova NA (2014) Polym. Sci. A (Russia) 56:48–62Google Scholar
- 26.Kochervinskii VV, Kozlova NV, Bessonova NP, Shcherbina MA, Pavlov AS (2014) J Mater Sci Res 3:59–73Google Scholar
- 27.Kochervinskii VV, Pavlov AS, Kozlova NV, Shmakova NA (2014) Polymer Sci. A (Russia) 56:587–602Google Scholar