Characterization and Application of PVDF and Its Copolymer Films Prepared by Spin-Coating and Langmuir–Blodgett Method

Abstract

Poly(vinylidene fluoride) (PVDF) and its copolymers are key polymers, displaying properties such as flexibility and electroactive responses, including piezoelectricity, pyroelectricity, and ferroelectricity. In the past several years, they have been applied in numerous applications, such as memory, transducers, actuators, and energy harvesting and have shown thriving prospects in the ongoing research and commercialization process. The crystalline polymorphs of PVDF can present nonpolar α, ε phase and polar β, γ, and δ phases with different processing methods. The copolymers, such as poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)), can crystallize directly into a phase analogous to the β phase of PVDF. Since the β phase shows the highest dipole moment among polar phases, many reproducible and efficient methods producing β-phase PVDF and its copolymer have been proposed. In this review, PVDF and its copolymer films prepared by spin-coating and Langmuir–Blodgett (LB) method are introduced, and relevant characterization techniques are highlighted. Finally, the development of memory, artificial synapses, and medical applications based on PVDF and its copolymers is elaborated.

Superflexible and Lead-Free Piezoelectric Nanogenerator as a Highly Sensitive Self-Powered Sensor for Human Motion Monitoring

“…Figure 1 b shows a partial magnification of the diffraction peak of the three composites. Strong diffraction peaks at 2 θ = 17.7°, 18.4°, 19.9°, and 26.5° correspond to the α crystallographic reflections: (100), (020), (110), and (021) [ 47 ], and the weak peak at 20.3° is correspond to the (110) and (120) plane of β-phase [ 48 ], indicating the dominance of α-phase in PVDF.

Fig.

…”

Biopolymer Coatings for Biomedical Applications

“…There have been reports of effective coating using PVDF and its copolymers using the spin coating and Langmuir–Blodgett (LB) methods. Yin et al reviewed studies reporting the application of PVDF and its copolymer films using the spin coating and LB methods [ 39 ]. Several studies have reported that PVDF, along with other materials, form a composite or combination of materials that offer the advantages of both materials [ 22 , 23 , 24 , 28 , 29 , 31 , 33 , 35 , 36 , 37 , 38 , 39 ].…”

Synthesis of vinyl ester resin-carrying PVDF green nanofibers for self-healing applications

“…In addition, as investigated by Mi et al, the dipoles of β crystals relating to the peaks 1401, 1274 and 840 cm −1 are in the orthogonal direction and corresponding relative intensity can be used to determine the lattice orientation 38 . Meanwhile the interaction between C–H … F–C is a dipolar dispersion force, wherein PVDF, a non-conjugated linear fluorinated hydrocarbons and TPS also contain carbon and hydrogen resulting in transient dipole moment lead a separate transient dipole moment in neighboring molecule, initiating a fleeting attraction between the C–H molecules 39 . The remaining characteristic bands were mostly contributed by PVDF which as follows: (1) 3400–3427 cm −1 : stretching vibration mode of the hydrogen-bonded O H groups of starch, (2) 1625–1629 cm −1 : double bond interaction of C to C; (3) 1185–1190 cm −1 the retain stretching vibration of C–F; and the (4) 883–884 cm −1 : confirmed the C=C bonding in bending movement.…”