Titanium sulfones, preparation

Chloroethyl benzoate has been prepared from benzoyl chloride and ethylene chlorohydrin from benzoic acid, ethylene glycol, and hydrogen chloride at 100° from ethylene oxide and benzoyl chloride from benzoyl chloride and dioxane in the presence of titanium tetrachloride from benzoic acid, ethylene, and chlorine in the presence of various catalysts. It has also been obtained by hydrolysis of 2-chloroethyl benzimidate " by the action of bromomagnesium benzoate on 2-chloroethyl -toluene-sulfonate and by the action of sodium benzoate on bis-(2-chloroethyl) sulfate. ... 

Ti and Zr containing polytetramethylene oxide (PTMO) ceramic hybrid materials have lately been prepared by a sol-gel technique [61, 62]. Trialkoxy silane capped organic oligomer (PTMO or polyarylene ether sulfones) backbones with titanium isopropoxide or Zr-(n-propoxide) are used in this process ... 

The preparation of nanocomposite membranes by intra-membrane growth within a proton exchange membrane was first described by Mauritz et al. [45-47]. The then novelty of this approach and the breadth and depth of these studies warrant the following discussion of the results, which in many ways laid the foundation for future work in this area. This group made use of the hydrophilic ionic cluster regions of Nafion for confined, sulfonic acid group catalysed, hydrolysis/condensation reactions of impregnated alkoxides. Nafion membranes were first swollen in ethanol/water, then tetraethoxy-silane (or aluminium, titanium and zirconium alkoxides) permeated from one side of the membrane. In addition to the concentration profile of in-... 

Bearing these considerations in mind, Reddy and Verkade prepared a titanium alkoxide complex, 72, with good stability toward moisture for the selective oxidation of sulfides to sulfones and sulfoxides with hydrogen peroxide in recyclable ionic liquid solvents at room temperature [56]. They optimized reaction conditions and recovering procedure for thioanisole 71, and used their obtained results for oxidation of different aliphatic, aromatic and xmsaturated sulfides. Their results proved the chemoselectivity... 

Polyaniline (PAn)/inorganic composites have been considered as new class of materials due to their improved properties compared with those of pure conducting polymers and inorganic materials [73-77]. For example, the combination of electrical conductivity of PAn and UV sensitivity of anatase Ti02 are expected to find applications in electrochromic devices, nonlinear optical system, and photochemical devises [73], From this point of view, it is in particular interest to prepare fluoroalkyl end-capped oligomers/PAn/titanium oxide nanocomposites. In fact, fluoroalkyl end-capped acrylic acid oligomer [Rp—(ACA) —Rp]/, 2-methacryloyloxyethane sulfonic acid oligomer [Rp—(MES) —Rp]/, 2-acrylamido-2-methylpropanesulfonic acid... 

Biodegradable copolyesters patented by BASF [62, 63] are prepared by the initial condensation of 1,4-BDO and adipic acid to afford polytetramethylene adipate. This polymer is reacted with dimethyl terephthalate, 1,4-BDO, pyromellitic dianhydride and polyethylene glycol (MW of 600), in the presence of a titanium catalyst. A sulfonate compound is optionally incorporated into the polymer. 

Devrim, Y., Erkan, S., Bac, N., and Eroglu, I. (2009) Preparation and characterization of sulfonated polysulfone/titanium dioxide composite membranes for proton exchange membrane fuel cells. Int J Hydrogen Energy, 34, 3467-3475. 

Due to these problems, research on the development of alternative PEM has been carried out to minimize the shortcomings. Developments in preparing new membranes can be classified into three different branches such as (1) synthesizing new polymers based on nonfluorinated backbones [7,8] (2) incorporating inorganic fillers such as montmorillonite (MMT) [9], palladium alloy [10], silicon [11], titanium oxide [12], and zeolite [13] into parent polymer matrices and (3) sulfonated polymers [14,15]. 

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