Organosiloxane copolymers synthesis

The main reason for the investigation was to create convenient methods for the synthesis of organosiloxane copolymers with monocyclosiloxane fragments in the side chain. To establish the influence of the cyclic fragment on the properties of copolymers the initial difunctional organodichlorosiloxyorganocyclosiloxanes and a new class of cyclolinear copolymers, with monocyclic fragments in the side chain were synthesised. 

Synthesis of Organosiloxane Copolymers with Monocyclic Fragments in the Side Chain... 

Poojari Y, Palsule AS, Cai M, Clarson SJ, Gross RA. Synthesis of organosiloxane copolymers using enzymatic polyesterification. Eur Polym J2008 44 4139 5. 

In this section of our review, recent developments in the synthesis of organosiloxane containing multiphase copolymers and networks will be discussed. Basic structural and physical characteristics of the copolymers (e.g. spectroscopic, thermal, molecular weight, etc.), supporting the formation of the multiphase structures will be given. Mechanical and morphological characteristics of representative systems will be discussed in Chapt. 4. 

Besides their unique combination of properties, another important factor that makes organosiloxanes so attractive in the synthesis of block copolymers, is the ease of... 

Belorgey, G. Sauvet, G. Organosiloxane Block and Graft Copolymers. In Silicon-Containing Polymers. The Science and Technology of Their Synthesis and Applications Jones, R G., Ando, W., Chojnowski, J., Eds. Kluwer Dordrecht, 2000 Chapter 2, pp 43-78. 

Thus, synthesis of cyclolinear organosiloxane and carbosiloxane copolymers with monocyclic frag-ments in the backbone, obtained in HFC, hydride polyaddition and polymerization reactions, are considered in this review. The above-shown data on high-molecular polymers with regular dispo-sition of cyclic fragment in the backbone are mainly synthesized by HFC and hydride polyaddition reactions. As for polymerization of bicyclosiloxanes, they are almost useless for high polymer syn-thesis. 

Polymeric initiators based on azo or triazene modified poly(organosiloxane)s can be used to synthesize graft copolymers with silicone backbone and thermoplastic side chains. The azo functionality has some advantages such as lower thermal stability, known reaction mechanism, no homopolymer formation and cleaner graft products. However, the synthesis of the triazene polymeric initiators requires fewer synthetic steps. The graft products microseparate but form stable films. 

Ellis, S. R. M. 1971. Vapor phase extraction process. Br. Chem. Eng. 16 358. Elsbernd, C. S. 1988. Synthesis, kinetics, and supercritical fluid fractionation studies of functional organosiloxanes and their incorporation into segmented copolymers. Ph.D. diss., Virginia Polytechnic Institute and State University. 

Ibemesi, J. Gvozdic, N. Keumin, M. Tarshiani, Y. Meier, D. J., Synthesis and Properties of Copolymers of DiphenylsUoxane with Other Organosiloxanes. In Polymer-Based Molecular Composites, Schaefer, D. W. Mark, J. E., Eds. Materials Research Society Pittsburgh, PA, 1990 Vol. 171, pp 105-115. 

There is a continuing high activity in the synthesis, and stnicture/property relationships of copolymer systems in which organosiloxane forms part of the main chain, and more recently, in which silicon atoms alone form the main chain. Developments in the more important of these polymer systems are reported. 

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