Yunyun Wang,Li Chen,Yinhua Jiang,Xinyan Yang,Jiangdong Dai,Xiaohui Dai,Mingdong Dong,Yongsheng Yan
Applying polyvinylidene fluoride (PVDF) monolith for phosphates removal can improve the operability of the adsorption process compared with some other powder nanomaterials. However, as the commonly used synthesis strategy, non-solvent induced phase separation (NIPS) was deemed not environmentally friendly enough since the dissolution of PVDF often involved volatile organic compounds (VOCs). This article designed a salt sacrificial template method to fabricate a 3D porous PVDF monolith, and then in-situ growth of lamellar La(OH) 3 on the PVDF foam was realized to enhance the adsorption affinity to phosphates pollution. No VOCs were used or released during the whole synthesis process. The adsorption for phosphates was as high as 56.2 mg g −1 , and easy reusability of the novel PVDF monolith was realized. In addition, this PVDF-La(OH) 3 foam exhibited good adsorption properties in both oil and water environments, which implied it could not only adsorb phosphates in actual water samples but also separate oil contaminants from water. All these implied that this PVDF-La(OH) 3 foam could be a potential candidate for large-scale industrial adsorption and separation of phosphates. This PVDF-La(OH) 3 foam could be a potential candidate for large-scale industrial adsorption and separation of phosphates.
Wen-Gang Cui,Xiaodi Zhou,Biao Zhao,Wenbin You,Yaxiong Yang,Bingbing Fan,Limin Wu,Renchao Che
Recently, the three-dimensional (3D) porous cellular foam derived from poly (vinylidene fluoride) (PVDF) via a simple CO 2 -assisted procedure has been widely applied as electromagnetic (EM) wave absorbing materials due to its one-step preparation process and high void fraction. However, delicate control of 3D microcellular structure by decoration of dielectric/magnetic components is still virgin. Herein, the hierarchical structure of 3D PVDF foam decorated with an ultra-low content of graphene nanoplates (5.0 wt%) and Ni nanochains (2.4 wt%) was successfully fabricated. The correlation between microcellular structure, and electrical conductivity/microwave absorption was systematically investigated. After introducing the conductive and magnetic components, a strong enhancement of dielectric loss, coming from the presence of conduction loss and polarization loss of 3D network, and magnetic loss, originating from strong eddy current loss and the natural resonance, was observed. Meanwhile, a high void fraction (∼92%) greatly optimized the impedance matching of incident waves and favored the multi-scattering. As a result, the superior microwave absorption was obtained, in which the effective absorption bandwidth (frequency with 90% microwave dissipation) can cover the whole K band (18–26.5 GHz) under the thickness of 3 mm. Overall, this work provides an ameliorated strategy for porous foams applied in microwave absorption.
危险品化学品经营许可证（带存储）