Titania thermal analysis

Polydimethylsiloxane and Zr oxo species have been reacted to give hybrid materials which were characterized by solid-state NMR.149 TEOS/PEG (polyethylene glycol) materials are biphasic systems. The materials were studied by 13C NMR, EPR, and thermal analysis.150 Other systems studied include titania/polyvinylacetate,151 titania/PEG,152 silica/polyacrylates,153 polyimide/ silica,154"156 linseed oil alkyds/titania,157 and PVC/titania and vanadia/sulfonated polyaniline... 

The sol-gel titania-silica mixed oxide contained 20 wt% titania. The catalyst was synthesized imder acidic conditions [5]. The acidic hydrolysant was added to an isopropanohc solution of tetraisopropoxytitanitam(IV) modified by acetylacetone (molar ratio alkoxide acetylacetone =1 1) and tetramethoxysilicon(IV). The water alkoxide acid molar ratio was 5 1 0.09. The resulting gel was dried by semicontinuous extraction with supercritical COg at 40 °C and 240 bar, and stored in a closed vessel under Ar. After calcination in flowing air at 600 °C, the BET smface area was 648 m g and the specific pore volume 2.9 cm g". Details on the synthesis and characterization of the sol-gel titania-sihca by means of FTIR, Raman and UV-vis spectroscopies, Ng-physisorption, XRD, XPS, TEM and thermal analysis have been reported previously [5, 6, 14, 15]. 

In view of this, nano titanium dioxide was synthesized and prepared as suspension with PVP solution. The mixture was set to electro-spin into fibre at 18KV. The e-spun fibre was subjected to differential thermal analysis to obtain the sintering profile for the titania fibre. The titania fibre was sintered at 500°C and 1200°C. The sintered phases and microstructural of titania fibre were analysed by using X-ray diffractometer and scanning electron microscope and presented. The cross-linked titania fibre formed a web-like structure maybe reduced the nano risk as compared to the nanoparticles. 

In this framework, in the specially designed mortars consisting of binders of either lime and metakaolin or natural hydraulic lime and fine aggregates of carbonate nature, nano-titania of anatase (90 per cent) and rutile (10 per cent) form has been added (4.5-6% w/w of binder). The aim was to study the effect of nano-titania in the hydration and carbonation of the above binders and to compare the physico-chemical properties of the nano-titania mortars with those mortars without nano-titania, used as reference. Thermal analysis (DTA-TG), infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses were performed to investigate the evolution of carbonation, hydration and hydraulic compound formation during a six-month curing period. Furthermore, the stone-mortar interfaces, the adhesion resistance to external mechanical stress, relative to the physicochemical characteristics of the stone-mortar system and the role of the nano-titania as additive, were reported and are discussed in this chapter. 

Figure 3. Differential thermal analysis of ahimina-titania supports. Air atmosphere, lO C/min. Samples a) AT05 b) ATIO c) AT40.

Nishide, T., T. Tanaka, T. Yabe (2004) Temperature programmed desorption analysis of sol-gel-derived titania films. Journal of thermal analysis and calorimetry. 90,373-378. 

TOA. See Thermogravimetric analysis Theory of deformation, 437-448 Thermal analysis, 16, 549, 570, 604, 711 Thermal conductivity, 760 Thermal decomposition, 272 Thermal expansion, 506, 550, 551, 554, 702, 737, 748-751, 760, 766-767 titania silica xerogels, 295, 597, 598, 776 Thermal stress, 436, 494 Thermodynamic activity, 474 Thermodynamic barrier, 732-735, 752-753 Thermodynamics, sols, gels, glasses,... 

The structures of the gold catalysts were observed using a Hitachi H-9000 electron microscope operated at 300 kV. X-ray diffraction (XRD) analysis was made by using a Rad-B system (Rigaku Denki Co.Ltd.). Infrared spectra were taken with a Nicolet 20-SXC spectrometer. For the IR analysis, each sample was mixed with KBr( 2wt.% for magnesia 10 wt.% for titania), and pressed into a thin wafer. Differential thermal analysis (DTA) was made by using a SSC-5200 thermal analyzer (Seiko Denshi Kogyo Co.Ltd.). X-ray photoelectron spectroscopy (XPS) was measured with a SSX-100 spectrometer (Surface Science Laboratories, Inc.). 

Data showing dehydrogenation onset temperature as determined by thermal gravitational analysis (TGA) and oxide surface area for MgH2 milled for 20 h with 20 wt% of various oxides (Croston, 2007). Nomenclature of y-axis labels refers to the wt% ratio of oxides followed by the calcination temperature of the oxide particle in °C. The Ti-5Pd and Ti-IPd refer to 5 and 1 wt% Pd distributed on the 20 wt% titania. Unmarked row represents milled MgH2 with no additive. 

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