The influence of shaped TiO2 nanofillers on thermal properties of polyvinyl alcohol

Abstract

PVA-based nanocomposites consisting of shaped TiO2 nanocrystals (nanoparticles, nanotubes or nanorods) were synthesized by direct blending of polymer and titania nanocrystals solution or powder. In order to elucidate the influence of shape of titania nanocrystals on thermal stability of polymer matrix and particles interaction with PVA chain, structural and thermal characterizations of PVA/TiO2 nanocomposites were performed. Faceted nanoparticles increased the thermal stability of PVA matrix. Titania nanotubes and nanorods did not show any stabilizing effect on polymer matrix in argon atmosphere. The thermo-oxidative degradation temperature of PVA increased with addition of faceted TiO2 nanoparticles. The thermo-oxidative stability of the PVA matrix was affected more by the presence of titania nanotubes and nanorods in comparison with its thermal stability in inert atmosphere. The crystallinity degree (Xc=32 %) of PVA matrix slightly decreased in the presence of faceted TiO2 nanoparticles in nanocomposite sample

Effect Adding PVA Polymer on Structural and Optical Properties of TiO2 Thin Films

“…(5) shows the variation of refractive index (n) with photon energy of the prepared thin films. The increase may be attributed to higher packing density and the changes in the particle size distribution function of TiO2 structural, this the enhancement of growth crystalline this attributed to the molecules of TiO2 come close together when add PVA polymer [3,6] . …”

“…TiO2 have the outstanding proportion of high refractive index (N2.5), excellent transmittance in visible as well as high electrical and chemical stability. It has been studied extensively for using in optoelectronic device [4,5] TiO2 was used as electron accepting material because of its non-toxic and abundance availability to indentify physical and structural properties of semiconductor material, the scope of thin films has enabled this opportunity to study semiconductors through the preparation of films [6], because of easily breaking the thin film which is does not exceed only microns thick it is deposited on certain substrate ,such as glass, silicon ,and alumina [7] . TiO2 is found naturally as white material, in three forms of crystalline, Rutile (tetragonal), Anatase (tetragonal), and Brokite (orthorhombic) [8] , TiO2 films can be prepared by different techniques, such as thermal evaporation in vacuum deposition (TEVD), chemical vapor deposition (CVD), pulse laser deposition (PLD) chemical spray pyrolysis deposition (CSPD) and other method [9,10,11] .…”

“…Polyvinyl Alcohol (PVA) is a white and granular, it is soluble in hot water but insoluble in cold water and common organic solvents for many applications [12] , this polymer chose in this research because of its relative ability for preheating (comparing with other polymers) to deposited on glass. Polyvinyl Alcohol is prepared in water solutions on evaporation of water, transparent films are formed which have high tensile strength and tear resistance [6] , PVA polymer has a melting point of 180°C [13] and it has a molecular weights (26,300, 72,000 and 30,000) g/mol [14] . The aim of this research is study adding PVA polymer on some structural and optical properties of TiO2 thin films which prepared by chemical spray pyrolysis technique.…”

Effect of fabrication technique on microstructure and electrical conductivity of polyaniline-TiO 2 -PVA composite material

“…(2004), Huyen, D. N. et al (2011), Olad, A. et al (2012), Ays, E. et al (2007) and Abduljalil, H. et al (2011), due to their potential applications in chemistry, physics, electronic, optics and biotechnology. Radoicic, M. B. et al (2012) also established that TiO 2 nano particles increased the thermal stability of PANI, whereas Hao, X. and Li, F., (2011) found that it improved the water resistance,due to strong hydrogen bonding interaction with PVA molecules. The yield of PANI was studied by Subramanian, E. et al (2012) and found that it was increased by encapsulation of TiO 2, in PVA.…”

Fabrication and characterization of electrospun PVA/CdS and PVA/TiO2 nanocomposite thin films as n-type semiconductors

“…Life of the composites and their brightness of light emission are enhanced by the existence of semiconductor nanoparticles in polymeric matrices [28]. Nanocomposites impart several advantages such as greater chemical and thermal stability, increased strength, enhanced electrical conductivity, and improved flammability properties to polymeric matrix [29].There are many reports on the synthesis of semiconductor nanoparticles embedded into polymeric matrices [27,28,[30][31][32][33][34][35][36].…”