PVDF based nanocomposites produced by solution blow spinning, structure and morphology induced by the presence of MWCNT and their consequences on some properties

摘要

Nanocomposites based on poly(vinylidene fluoride), PVDF, filled with multiwalled carbon nanotubes, MWCNT, were prepared by solution blow spinning, SBS. PVDF was modified with MWCNT with the aim of changing final properties inducing structural and morphological variations in the polymer by the simple presence of conductive particles. Different compositions were considered (0%, 1%, 2%, 3%, and 5% by weight of MWCNT) to understand the influence of the presence of MWCNT on the polymer structure, morphology, and consequently other properties. Morphology was inspected by optical and electron (SEM and TEM) microscopies, while structure was studied by Fourier transformed infrared spectroscopy, FTIR. Thermal behavior was monitored by differential scanning calorimetry, DSC, while the surface and electrical properties were studied by contact angle and capacitance measurements, respectively. SBS allowed obtaining mats of nanocomposites constituted by submicrometric fibers where the MWCNT are uniformly dispersed and well aligned along the PVDF fibers. In this study, several aspects about structure and thermal behavior of PVDF were clarified in relation to other researches carried out up to the moment. Although MWCNT concentration did not seem to affect much the fibrous morphology of the SBS materials, the PVDF crystalline structure and surface properties of the materials were slightly modified. Dielectric behavior of PVDF was highly affected by the presence of MWCNT leading to a particular change in the permittivity and being possible to obtain a value of 0.023 for the percolation fraction.