Effect of TiO₂ nano‐filler on the electrical conductivity and free volume parameters of PSAN/TiO₂ nanocomposites

Abstract

To explore the effect of filler on the electrical conductivity of polymer nanocomposites, polystyrene coacrylonitrile and TiO 2 (PSAN/TiO 2 ) nanocomposites of different TiO 2 wt% have been prepared. The microstructural characterization has been performed by positron annihilation lifetime spectroscopy (PALS). Positron lifetime parameters viz. o-Ps lifetime (s 3 ) and free volume size (V f ) decreases up to 0.6 wt% suggests the filling of the cavities by Ti 31 and O 2 ions as well as complex formation. The increased free volume size (V f ) after 0.6 wt% of TiO 2 was attributed to the o-Ps annihilation at the interface of PSAN and TiO 2 nanoclusters. The variation of electrical conductivity at lower and higher concentration of TiO 2 is attributed to the blocking effect and space charge effect, respectively. The electrical conductivity decreases along with the free volume sizes at lower concentration of TiO 2 due to the hindrance of the ions mobility. The increased conductivity with the increased free volume sizes indicates the formation of more void space at the interface due to the formation of TiO 2 nanoclusters. The surface morphology of the nanocomposites studied by scanning electron microscopy (SEM) shows uniform dispersion at the lower wt% of TiO 2 and increased size of nanocluster formation at the higher concentration of TiO 2 nanoparticles in PSAN matrix. The crystallinity evaluated by X-ray diffraction (XRD) results also indicates the formation of TiO 2 nanoclusters between 0.6 and 1.0 wt% of TiO 2 . Fourier transform infrared spectroscopy (FTIR) suggests the improved chemical and physical interaction between the functional groups of TiO 2 and polymer side chain. POLYM. COMPOS., 00:000-000,

Positron lifetime study of PAN‐based carbon fiber‐reinforced polymer composites

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Palladium complex embedded crosslinked polystyrene nanofibers as a green and efficient heterogeneous catalyst for coupling reactions

“…PALS is a sensitive technique to measure the free volume hole size and concentration. 25,26,29 For comparison, polystyrene nanofibers (PS) and crosslinked polystyrene nanofibers (CPS) were also prepared and analyzed by PALS. As the crosslinking of polystyrene molecules would restrict the movement of polymer chain, both the size and concentration of free volume holes in these composite nanofibers were reduced after crosslinking.…”

Physico‐mechanical, thermal, and ultraviolet light barrier properties of collagen hydrolysate films from leather solid wastes incorporated with nano TiO2

“…[3,14,59] Furthermore, the observed increase of O H and N H stretching vibrations, as the concentration of TiO 2 NPs increased in the films, could be ascribed due to the number density of Ti OH bonding. [41,60] Moreover, after the addition of TiO 2 NPs, the peak was shifted to lower wavenumber of 2661 cm −1 could be ascribed to the intermolecular interactions between O H groups and N H groups from CH and TiO 2 NPs in the films. Thus, these new formed bonds indicate that TiO 2 NPs has been successfully incorporated into the CH matrix.…”

“…TiO 2 is a characteristic filler and exists in three crystalline forms; anatase, rutile, and brookite, and is obtained in different sizes, shapes, and surface features . Due to the small size and high surface area, TiO 2 NPs possess unique physical and chemical properties and can interact with the polymer to enhance the mechanical and physical properties of polymers …”

“…[36][37][38][39] Due to the small size and high surface area, TiO 2 NPs possess unique physical and chemical properties and can interact with the polymer to enhance the mechanical and physical properties of polymers. [33,40,41] However, to date, no previously report available on the reinforcement potentials of CH films extracted from leather solid wastes with TiO 2 NPs. The present article aims to investigate the effects of TiO 2 NPs on the structural, thermal, physical, and barrier properties of CH-based films.…”