Tunable Mechanical and Electrical Properties of Coaxial Electrospun Composite Nanofibers of P(VDF-TrFE) and P(VDF-TrFE-CTFE)

• Main Authors: Tu-Ngoc Lam, Chia-Yin Ma, Po-Han Hsiao, Wen-Ching Ko, Yi-Jen Huang, Soo-Yeol Lee, Jayant Jain, E-Wen Huang
• Format: Article
• Language: English
• Published: MDPI AG 2021-04-01
• Series: International Journal of Molecular Sciences
• Subjects: coaxial electrospun core/shell nanofibers; tensile modulus; wide-angle X-ray diffraction; dielectric constant; piezoelectricity
• Online Access: https://www.mdpi.com/1422-0067/22/9/4639
• ISSN: 1661-6596; 1422-0067

The coaxial core/shell composite electrospun nanofibers consisting of relaxor ferroelectric P(VDF-TrFE-CTFE) and ferroelectric P(VDF-TrFE) polymers are successfully tailored towards superior structural, mechanical, and electrical properties over the individual polymers. The core/shell-TrFE/CTFE membrane discloses a more prominent mechanical anisotropy between the revolving direction (RD) and cross direction (CD) associated with a higher tensile modulus of 26.9 MPa and good strength-ductility balance, beneficial from a better degree of nanofiber alignment, the increased density, and C-F bonding. The interfacial coupling between the terpolymer P(VDF-TrFE-CTFE) and copolymer P(VDF-TrFE) is responsible for comparable full-frequency dielectric responses between the core/shell-TrFE/CTFE and pristine terpolymer. Moreover, an impressive piezoelectric coefficient up to 50.5 pm/V is achieved in the core/shell-TrFE/CTFE composite structure. Our findings corroborate the promising approach of coaxial electrospinning in efficiently tuning mechanical and electrical performances of the electrospun core/shell composite nanofiber membranes-based electroactive polymers (EAPs) actuators as artificial muscle implants.