Ti-isopropoxide

The synthesis of 5 lan thick Ti02 Si02 layers on a porous support can be performed using the procedure given below. First a mixed Ti[(OMe)3]4 alkoxide is synthesized by reacting partially hydrolyzed Si(OMe)4 with Ti-isopropoxide. This inorganic polymer is hydrolyzed at pH 11.0 and treated with 2-methyl-2-4-pentanediol and a binder. This solution is then slip-cast onto a porous support, dried and calcined at 700°C. The membrane can be useful in reverse osmosis applications. 

All mesoporous titanosilicates obtained by the Ti-isopropoxide grafting exhibit the same XRD patterns and the intensity remained almost constant as those for their pure silica analogues as shown in Figure 1. These confirm that structural integrity of the mesoporous materials remained intact after TIPOT grafting treatment. 

Titanium-pillared montmorillonite may be used as a heterogeneous catalyst for the Sharpless asymmetric epoxidation of allylic alcohols (Scheme 20) (46). The enantiomeric purities of the epoxy products are comparable with those achieved using homogeneous Ti isopropoxide with molecular sieves as water scavengers (Chapter 4). Since basal spacing of the recovered catalyst after the reaction is unaltered, the catalyst can be recycled. 

Thin-film dielectrics (Ba0 92Ca108)(Ti0 92Zr0 08)O3 for the thin-film capacitors were prepared using Ba, Ca, and Zr ethoxides and Ti isopropoxide in refluxed methoxyethanol solutions as precursors. Films were deposited on a usual platinized Si substrate. Crystalline thin films after heat treatment at 800°C demonstrated dielectric permittivity of 1200, dielectric loss of0.5%, nonlinear coefficient a = 0.92, and break-down voltage of980 V [1595],... 

A. mixture of Ti isopropoxide and Zr -propoxide was hydrolysed in water. The hydroxide was thermally decomposed at different temperatures for 3 h. 

PZC/IEP of Titania-Zirconia Composite Obtained from Ti Isopropoxide and Monoclinic Zirconia... 

Iron-molybdenum-titanium oxides were prepared via the sol-gel method. Either (NH4)6Mo7024 4H20, and ferric nitrate (FeN), Fe(N03)3-9H20, or FeCb and MoOCL were used as precursors together with Ti-isopropoxide. These solids were characterised by chemical analysis and N2 adsorption. The sol-gel samples developed higher surface areas (c.a. 100 m g ), except for the sol-gel solid prepared with Fe and Mo chlorides as precursors, than those prepared by impregnation. 

Z (3S,4R)-4-Hydroxy-3,5-dimethyl-1-hexenyl N, N-diisopropylcarbamate 5.2 (E)-Butenyl carbamate 1 (408 mg, 2 mmol) diluted with pentane (2 mL) was added slowly to a solution of sparteine (514.8 mg, 2.2 mmol) and BuLi (2.5 mmol in hexane 1.6 N) in pentane/cyclohexane (7 mL + 1.5 mL) and stirred vigorously. To this precooled suspension precooled Ti isopropoxide (4-10 mmol) was added very quickly at -70°C and stirring was continued for 15 min. 2-Methylpropanal 4 (360 mg, 5 mmol) was injected and the reaction mixture was allowed to warm to 20°C. Quenching with 2N HCI (10 mL) was followed by extraction with Et20. The residue obtained after evaporation of the solvent was purified by LC (silica gel Et2Oipentane) to provide 488 mg of 5 (90%). 

In the case of MWCNT/Ti02 gas sensors, Sanchez and Rincon employed dip-coating based on a sol-gel solution. The sol-gel solution containing Ti-isopropoxide and add treated MWCNTs was either precipitated or kept as a sol by adjusting the pH and surfactant concentration. 

Precursor preparation Modify Ti-isopropoxide with acetic acid... 

Herrig and Hempelmann [256] used a reverse method, i.e. poured a microemulsion in the system Brij 30/cyclohexane/water into a solution of Ti-isopropoxide in isopropanol (1 1 volume ratio). The precipitate was collected by centrifugation and acetone washing, or Soxhlet extraction with cyclohexane. The particles, when heated at 600 C/6h, had an average crystallite size of 10 nm. 

Equimolar quantities of Ba- and Ti-isopropoxide were mixed in isopropanol and added to the microemulsion. Isopropanol and cyclohexane were evaporated at 60°C under vacuum to obtain a solid product which was purified by Soxhlet extraction with cyclohexane to obtain phase-pure BaTi03 at room temperature (particle size < 20 nm). 

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