Functionalized siloxanes

Carbofunctional siloxane oligomers see Organo-functional siloxane oligomers Carbonionic sites, nucleophilicity 155... 

The properties and applications of five commercially important groups of silanes those containing Si-H (hydride functional silanes), Si-X (halosilanes), Si-C (organosilanes), Si-OSi (siloxanes), and Si-OR (silicon esters) are thoroughly discussed by Arkles.14 As the role of functional siloxanes grows, so does the importance of the hydrosilylation reactions in this field. A broad introduction to hydrosilylation processes as applied to the synthesis of silicone precursors and to the functionalization of siloxanes is provided in the earlier editions of COMC, and,... 

Silicone fluids can be discussed in two categories inert fluids and functional fluids, the latter including silicon-functional and organo-functional210 (modified) polymers. The methods of synthesis of functional siloxanes have recently been reviewed.378... 

Matisons, J. G. Provatas, A. Synthesis and Characterization of Amino Acid Functional Siloxanes. In Silicones and Silicone-Modified Materials-, Clarson, S. J., Fitzgerald, J. J., Owen, M. J., Smith, S. D., Eds. AGS Symposium Series 729 American Chemical Society Washington, DC, 2000 pp 128-163. 

Side chain furan functionalization has been accomplished by acetalization (Section 1.11.4.4.3) of poly(vinyl alcohol) (180) with furan-3-carbaldehyde (181 Scheme 87) (72MI11106). The adduct (182) was utilized as the diene reactant in a Diels-Alder reaction to bind vinyl-functional siloxane oligomers to the polymer. 

Another class of functional siloxane polymer that has received some attention are the fluorosiloxane materials, especially 3,3,3-trifluoropropylmethylsiloxanes. The use of conventional equilibration catalysts to produce these materials gives products which favour the cyclosiloxane in the bulk. Clarson and coworkers41 report the use of specific condensation catalysts such as stannous octanoate, potassium carbonate and barium hydroxide to prepare hydroxy terminated fluorosilicone polymers. 

Poly(methyl methacrylate)-g-poly(dimethylsiloxane) copolymers have been prepared by free radical copolymerizations of acrylate-functional siloxane macromonomers (29) with methyl methacrylate. Siloxane macromonomers (29) of between 1,000 and 20,000 molecular weight were utilized to give a range of copolymers with between 4 and 17 wt% silicone115. 

Snow, S.A., Fenton, W.N. and Owen, M.J. (1991) Zwitterionic organofunctional siloxanes as aqueous surfactants - synthesis and characterization of betaine functional siloxanes and their comparison to sulfobetaine functional siloxanes. Langmuir, 7(5), 868-71. 

Martiz, B., Keyrouz, R., Gmouh, S., Vaultier, M., and Jouikov, V. 2004. Superoxide-stable ionic liquids New and efficient media for electrosynthesis of functional siloxanes. Chemical Communications, 6 674—5. 

In a first step the epoxy-functionalized siloxanes were prepared by hydrosilylation, with allyl glycidyl ether and Lamoreaux catalyst (Pt catalyst resulting from HjPtClg.H O in octanol), at 130-145°C for 4-lOh. The reaction is quantitative. 

T. Ogawa, J. Polymer Sd., Part A Polymer Chem. 2003, 41(21), 3336-3345. Simplified synthesis of carbohydrate-functional siloxanes via transacetalation. 1. Glucose-functional siloxanes . 

We have obtained silsesquioxane-based polymer (HS-Polymer) by using the hydro-silylation reaction of vinyl-functionalized macromonomer (DD-2V) with some SiH-functionalized siloxanes (Scheme 4). 

Spectroscopic results about the interaction of the traditional spacer compound 3-aminopropyltri-ethoxysilane (APTES) with a silicon surface have already been discussed in the first part of this paper leading to the conclusion that a considerable improvement regarding the stability and durability of the amino-functionalized siloxane film is possible by using the 4-aminobutyltriethoxysilane (ABTES) rather than the propyl compound. 

Graft copolymers are obtained by subsequent radical emulsion polymerisation of olefinic unsaturated monomers in the presence of functionalized siloxane particles. Scheme 3 illustrates that the graft... 

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