Polyfvinylidene fluoride PVDF

Partially fluorinated polymers, notably polyfvinylidene fluoride) (PVDF) and its copolymers, are readily processed by conventional polymer technology and generally have chemi-... 

Most organic materials are slowly attacked by wet chlorine gas. Rubber-lined iron is successfully used up to 100 °C. At low pressure and temperature the use of plastic materials like PVC, chlorinated PVC, and reinforced polyester resins is advantageous. Polytetrafluoroethylene (PTFE), polyfvinylidene fluoride) (PVDF), and fluorinated copolymers like tetrafluoroethylene-hexafluoropropylene (FEP) are resistant even at higher temperature. Ceramics have been progressively replaced by plastics. Impregnated graphite is suitable up to 80 C the impregnation should be resistant to wet chlorine. 

Whereas ferroelectridty in polymers of the polyfvinylidene fluoride) (PVDF) type b induced by stretching and poling of polymers films and b not chaiacteristk for undisturbed samples, spontaneous polarization appears in liquid crystalline polymers with intrinsic lower symmetry Cj. 

Present researdi on physical properties, performance, and passible applications of electroactive polymers has oonceatraled < cooducting potymers because of their peculiar electrical properties, but the interest in polymers originally arose firom the rlieleciric ones. The strong piezoelectric effect in polyfvinylidene fluoride) (PVDF or PVFi) poled under high electric field was observed the first time by Kawai (1) in 1969, while its pyro-... 

Figure 1.11 SEM micrographs of the sulfonated PEEK/PVDF blend membranes with different amounts of PVDF (a) Mw = 180/XK) g/mol (b) Mw = 275,000 g/mol (c) Mw = 530,000 g/mol and (d) Mw = 130.000 g/mol PVDF-HFP (Polyfvinylidene fluoride-co-hexzafluoro propylene)). Reprinted from reference 10 with permission from International Association of Hydrogen Energy.

PCX poly(cyclohexylene terephthalate) PVDF polyfvinylidene fluoride)... 

The CH4-MDPE system, the 1,1-difluoroethylene + polyfvinylidene fluoride) C2H2F2-PVDF system, and the N2-PVDF system (all binary asymmetric systems) have been selected to illustrate the use of supercritical scanning transitiome-try [26, 29, 56]. These systems are of interest because they exhibit a pronounced nonideal behavior at elevated pressures due to the large differences in the molecular sizes of components. 

Shi, L., R. Wang, Y. Cao, D.T. Liang, and J.H. Tay. 2008. Effect of Additives on the Fabrication of PolyfVinylidene Fluoride-co-Hexafluropropylene) (PVDF-HFP) Asymmetric Micro-porous Hollow Fiber Membranes. Journal of Membrane Science 315(1/2) 195-204. doi 10.1016/j.memsci.2008.02.035. 

Prince, J.A., Singh, G., Rana, D., Matsuura, T., Anbharasi, V., Shanmugasundaram, T.S, 2012, Preparation and characterization of highly hydrophobic polyfvinylidene fluoride)-clay nanocomposite nanofiber membranes (PVDF-clay NNMs) for desalination using direct contact membrane distillation, JMemb Sci 397-398 80-86. 

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