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Polymer modification dimethyldioxirane solution

A series of novel styrene- and siloxane-based silanol polymers and copolymers were synthesized by a selective oxidation of the Si—H bond with a dimethyldioxirane solution in acetone from corresponding precursor polymers. The conversion of the Si—H to Si—OH in the polymer modification proceeded rapidly and selectively. The silanol polymers obtained in situ showed no tendency for self-condensation to form siloxane crosslinks in solution. Moreover, stable silanol polymers in the solid states were obtained by placing bulky substitute groups bonded directly to the silicon atom. It was found that the properties of these novel silanol polymers and copolymers depended largely on substituents bonded directly to the silicon atom and silanol composition in the copolymers as well. [Pg.179]

Polymer modification is of particular interest when the desired polymer is not readily available from its corresponding monomer by conventional polymerization methods. The primary challenge of polymer modification is to achieve a high conversion and selective modification of the appropriate functional group. In this paper, we describe a new convenient polymer modification to prepare novel silanol polymers by a rapid and selective oxidation of the Si—H bond with a dimethyldioxirane solution in acetone from their corresponding precursor polymers. [Pg.180]

A new convenient polymer modification has been developed to synthesize a series of novel silanol-containing polymers by a selective oxidation of Si—containing precursor polymers with a dimethyldioxirane solution in acetone. The silanol hydrogen bonding interactions in polymer blends as well as the silanol self-condensation to form siloxane semi-interpenetrating polymer networks in miscible polymer blends and organic-inorganic polymeric hybrids are discussed. [Pg.419]

Polymer Modification of the sSi—Containing Precursor Polymers with a Dimethyldioxirane solution in acetone. To a methyl ethyl ketone solution of sSi—H containing precursor polymers or copolymers, a cold solution (ca. -10 °C) of dimethyldioxirane in acetone was quickly added and reacted for 30 min at 0 °C. The mole ratio of dioxirane to polymer was ca. 1.2 1.3. The resulting silanol polymers or copolymers were obtained either in solution and used as is or precipitated into hexane followed by vacuum drying at 40 °C for 24 h. [Pg.421]

A new convenient polymer modification for synthesis of silanol-containing polymer was developed by the selective oxidation of the Si—H bond with a dimethyldioxirane solution in acetone. The oxyfunctionalization of the silane precursor polymers can be utilized to synthesize a wide variety of silanol-containing polymers. Control over the properties of these silanol polymers, such as stability and self-association of silanols, was realized through the placement of different substitute groups bonded directly to the silicon atom. The miscibility in either polymer blends or polymeric hybrids was achieved by the formation of strong inter-polymer hydrogen bonds between the... [Pg.430]




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Dimethyldioxirane

Polymer modification

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