Article
Polymer Science
Jia-Yi Ren, Qing-Feng Ouyang, Guo-Qi Ma, Yue Li, Jun Lei, Hua-Dong Huang, Li-Chuan Jia, Hao Lin, Gan-Ji Zhong, Zhong-Ming Li
Summary: This study proposes an efficient method to enhance the dielectric and ferroelectric properties of PVDF films through thermal treatment combined with pressure field. The appropriate pressure and temperature fields promote the alignment and phase transformation of PVDF films, resulting in films with high orientation and perfect beta-crystallites. These films exhibit enhanced dielectric and ferroelectric properties.
Article
Polymer Science
Zhubing Han, Hancheng Qin, Xin Chen, Wenhan Xu, Yang Liu, J. Bernholc, Qing Wang
Summary: The incorporation of comonomers in PVDF-based ferroelectric polymers has been widely used to modify their structures and properties. Previous studies have shown that large-sized comonomers can induce relaxor ferroelectricity, but this study demonstrates that a small-sized comonomer can preferentially adopt a polar all-trans conformation, resulting in terpolymers with robust ferroelectricity and enhanced transition temperature and coercive field. This work systematically investigates the effects of comonomer size on the microstructures and properties of ferroelectric polymers.
Article
Nanoscience & Nanotechnology
Qingqing Li, Jinghua Zhao, Baosheng He, Zhijun Hu
Summary: PVDF, a ferroelectric polymer with the polar beta-phase, has the highest dipolar moment and piezoelectric response. The development of flexible electronics highly requires effective methods for producing beta-PVDF.
Article
Polymer Science
Nikruesong Tohluebaji, Chatchai Putson, Nantakan Muensit, Jureeporn Yuennan
Summary: This study investigates the electrostrictive and structural properties of P(VDF-HFP) nanofibers modified with conductive polymer polyaniline (PANI). The composite nanofibers showed uniform fibers without bead formation, with decreased water contact angle and increased dielectric properties and electromechanical response as the PANI content increased. The results suggest that P(VDF-HFP)/PANI composite nanofibers may offer a promising route for electrostrictive applications in actuation, MEMS, and sensors.
Article
Materials Science, Multidisciplinary
Mathew Seena, Husna Jan, V. Prasad
Summary: This study reports the structural and dielectric properties of PVDF composites with FCNT prepared by hot pressing method, revealing an increase in overall polar phases and more gamma phases in the samples. The dielectric behavior and conductivity changes with hot pressing samples were studied through permittivity, electric modulus, and AC conductivity measurements.
MATERIALS CHEMISTRY AND PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
Dongxing Dun, Jingyun Luo, Minghao Wang, Xingran Wang, Hongfu Zhou, Xiangdong Wang, Bianying Wen, Yuxia Zhang
Summary: Polymeric electromagnetic interference (EMI) shielding foaming materials consisting of PVDF and CNTs are prepared in this study, with adjustable electrical conductivity and excellent EMI specific shielding effectiveness. The inclusion of CNTs enhances the performance of the composite system, and the foaming process provides a green and efficient route for the preparation of these materials.
MACROMOLECULAR MATERIALS AND ENGINEERING
(2021)
Article
Polymer Science
Wu Guo, Zhaogang Liu, Yan Zhu, Li Li
Summary: Based on a self-designed pan-mill mechanochemical reactor, a PVDF/GP nano-composite powder with high beta-phase content was prepared for micro-injection molding, resulting in micro-parts with good replication and dimensional stability. The high injection speed and small cavity of micro-injection molding induced a skin-core structure and increased crystallinity, leading to improved dielectric properties and mechanical strength of the micro-parts.
Article
Chemistry, Physical
Akanksha Adaval, Bharat B. Bhatt, Shiva Singh, Dipti Gupta, Pradip K. Maji, Mohammed Aslam, Terence W. Turney, George P. Simon, Arup R. Bhattacharyya
Summary: Two-dimensional layered nanomaterials (h-BN and EG) were incorporated into PVDF nanocomposites through high-shear solution mixing and compression molding. Ultrasonication and centrifugation were used to de-stack h-BN and EG, resulting in reduced agglomerate size. The nanocomposites showed improved dielectric properties and piezoelectric strain coefficients due to enhanced interfacial and dipolar polarizations. PVDF/EG and PVDF/h-BN nanocomposite films were further used to fabricate sensor devices with high peak-to-peak voltage values.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Seyed Mohsen Seraji, Xing Jin, Zhifeng Yi, Chunfang Feng, Nisa V. Salim
Summary: This study demonstrates the crystalline transformation of PVDF influences aerogel formation and compressible sensing properties of a graphene composite. The fabricated PVDF/graphene foams and aerogels show high sensitivity and improved compressive strength. The results provide new pathways for fabricating porous composites with lighter density and high mechanical and electrical properties.
Review
Physics, Applied
Yang Liu, Xin Chen, Zhubing Han, Huamin Zhou, Qing Wang
Summary: Defect engineering is a crucial strategy for designing high-performance ferroelectric polymers, which can tune various physical properties and structure-performance relationships. This Review summarizes the influence of defects induced by different monomers on the physical properties and structure of ferroelectric polymers, and discusses the effects of defect modification on dielectric, ferroelectric, electromechanical, and electrocaloric properties.
APPLIED PHYSICS REVIEWS
(2022)
Review
Chemistry, Multidisciplinary
Liwei Zhang, Shuangfeng Li, Zhiwen Zhu, Guanchun Rui, Bin Du, Dazhu Chen, Yan-Fei Huang, Lei Zhu
Summary: Poly(vinylidene fluoride) (PVDF)-based polymers have great potential for flexible and wearable electronics, but exhibit low piezoelectric coefficients. The improvement of PVDF's piezoelectricity involves modulating its semicrystalline structures, with debates on the primary contributor. Current methods for enhancing PVDF's piezoelectricity can be categorized as modulations of the amorphous phase, crystalline region, and crystalline-amorphous interface. This article discusses the principles, measurements, and strategies to improve PVDF's piezoelectric properties, emphasizing the crucial role of the oriented amorphous fraction at the crystalline-amorphous interface. Future developments in high-performance piezoelectric polymers are also discussed.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Polymer Science
Thulasinath Raman Venkatesan, David Smykalla, Bernd Ploss, Michael Wuebbenhorst, Reimund Gerhard
Summary: The effects of thermal processing on the micro- and nanostructural features and relaxor-ferroelectric properties of a P(VDF-TrFE-CFE) terpolymer were investigated. Annealing reduces the Curie transition temperature and shifts the ferroelectric phase fraction, leading to relaxor-ferroelectric behavior. Changes in transition temperatures are related to alterations in hysteresis curves.
Article
Materials Science, Composites
Jie Wang, Hui Li, Zeyun Wang, Dehua Xin, Jingyun Luo, Shijian Bai, Hongfu Zhou
Summary: Carbon nanotubes (CNTs) and graphene nanoplatelets (GNPs) were used as fillers in poly(vinylidene fluoride) (PVDF) composites to improve the electromagnetic interference shielding performance. The addition of CNTs and GNPs improved the conductivity and rheological properties of PVDF, and acted as nucleation agents to increase its crystallization peak temperature. The PVDF composites showed significant enhancement in storage modulus, complex viscosity, and electrical conductivity compared to pure PVDF. The new PVDF samples have potential applications as electromagnetic shielding materials due to their simple processing, low-cost, and solvent-free characteristics.
POLYMER COMPOSITES
(2022)
Article
Nanoscience & Nanotechnology
Jiale Fang, Chengqi Chen, Hongxing Qi, Jie Zhang, Xiaoxuan Hou, Likun Pan, Xianghui Wang
Summary: Developing flexible electromagnetic interference (EMI SE) shielding materials is crucial for protecting humans from harmful radiation. We designed and fabricated a flexible multilayer structure of PVDF/GNP-PVDF composite film, which exhibited high EMI SE performance (averaging 69.7 dB in X-band), excellent flexibility, and stability (98.85% retention after bending 1000 cycles at 60 degrees). The theoretical study indicates that the multiple reflection and absorption of electromagnetic waves between layers contribute to the high EMI SE performance of the PVDF/GNP-PVDF multilayer film.
ACS APPLIED NANO MATERIALS
(2023)
Article
Chemistry, Inorganic & Nuclear
Subramaniyan Vinoth, Sea-Fue Wang
Summary: The BaTiO3/PVDF nanocomposite prepared by cold sintering process showed good sintering density and microwave dielectric properties at low temperature, making it a promising candidate for microwave dielectric applications.
INORGANIC CHEMISTRY
(2023)
