Fluorination deposition on carbon nanofibers by PTFE decomposition as a facile method to enhance dispersion and interaction in PVDF composites

Abstract

A facile method for surface modification of nanofillers was developed in order to improve interfacial interaction and dispersion within poly (vinylidene fluoride) (PVDF) matrix. Rather than using the more conventional toxic fluorine gas method of treating nanofillers, a new method of depositing a fluorination coating from decomposition of polytetrafluoroethylene (PTFE) on a carbon nanofiber (CNF) surface was developed. The primary process parameters such as CNF/PTFE ratios and processing temperatures were studied through FTIR and morphological analysis. The fluorination coated CNFs (f-CNFs) were prepared successfully under the conditions of the CNF/PTFE ratio of 1 : 5 at 460 C. The morphological evidence showed that the enhanced dispersion of the f-CNFs and interfacial bonding with PVDF matrix were efficiently induced by the easily manipulated surface modification method. The coating effect for the CNFs was also clearly demonstrated from the electrical conductivity results by comparison of the nanocomposites with f-CNFs and as-received CNFs. Dynamic mechanical analysis results indicated that due to the surface coating on the CNFs, the contribution of the f-CNFs to the storage modulus was dramatically increased from $120 MPa to 1000 MPa at À90 C, an increase by a factor of about 8 times. This study confirmed that the new surface coating method provides a simpler way for practical modification of nanofillers, i.e. through decompositions of polymers, for treatment of nanofillers.

Effect of fluoropolymer composition on topochemical synthesis of SrMnO3−δFγ oxyfluoride films

“…These reaction temperatures are lower than the polymer decomposition temperatures, although it should be noted that decomposition begins at temperatures lower than those listed in Table 1. For example, although the decomposition temperature of PTFE is 460°C [24], slight decomposition was observed as low as to 230°C [25]; this reduced initiation temperature for decomposition is observed in PVF and PVDF [24]. We choose fluorination temperatures of 225°C and 235°C to preserve the crystallinity of the fluorinated oxyfluoride films and to prevent formation of secondary phases [19].…”

Molybdenum oxide nanoparticles: preparation, characterization, and application in heterogeneous catalysis

“…[8][9][10] Hence, studies on the degradation of waste PTFE materials are considered a matter of considerable importance. [11][12][13][14][15][16][17] Hlavaty and Kavan found that PTFE could react with alkali metals in organic solvents and produce highly reactive polyynes and metal fluorides. 15 Further, a comprehensive comparison concerning the degradation of PTFE under different conditions was reported by Gritsenko and Krasovsky.…”

Chemical and Morphological Transition of Poly(acrylonitrile)/Poly(vinylidene Fluoride) Blend Nanofibers during Oxidative Stabilization and Incipient Carbonization

“…Furthermore, the bending and stretching vibrations of CH 2 at 2935 and 1454 cm −1 , respectively, can be seen [ 19 ]. In addition, the bands at 1175, 880 and 765 cm −1 represent the symmetrical stretching of the CF 2 group, the asymmetrical stretching of C–C–C and the C–F stretching, respectively, that are commonly attributed to PVDF [ 47 , 84 , 85 , 86 ]. Therefore, the spectra show that both polymers are present in the as-spun blend nanofibers.…”

“…Another incentive is to implement persistent ingredients such as nitrogen [44], phosphorus [45] or nanofillers and particles [36,46] into the CNF to improve electrical or mechanical properties for instance. Depending on the desired field of application, this can likewise be achieved by post-treatment after carbonization by various methods [47][48][49][50]. The use of blend nanofibers produced by electrospinning binary polymer solutions can be an effective alternative route to producing differently doped carbon nanofibers with adjustable fiber morphology.…”