POLYMERIZATION OF HEXAMETHYLCYCLOTRISILOXANE

POLYMERIZATION OF HEXAMETHYLCYCLOTRISILOXANE

PURPOSE:To obtain a polymer having an especially narrow molecular weight distribution by subjecting hexamethylcyclotrisiloxane to living-anion- polymerization in the presence of a specific chelate compound in a polar solvent by using an initiator containing lithium cation. CONSTITUTION:This polymer...

Ausführliche Beschreibung

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Bibliographische Detailangaben
Hauptverfasser: OHATA MASATOSHI, IGA NOBUO, TANABE HISANORI, YAMAMOTO MASAHARU
Format: Patent
Sprache:eng
Schlagworte:
CHEMISTRY
COMPOSITIONS BASED THEREON
MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONSONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
METALLURGY
ORGANIC MACROMOLECULAR COMPOUNDS
THEIR PREPARATION OR CHEMICAL WORKING-UP
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Beschreibung
Zusammenfassung:PURPOSE:To obtain a polymer having an especially narrow molecular weight distribution by subjecting hexamethylcyclotrisiloxane to living-anion- polymerization in the presence of a specific chelate compound in a polar solvent by using an initiator containing lithium cation. CONSTITUTION:This polymer is obtained by subjecting hexamethylcyclotrisiloxane to anion polymerization preferably (A) by using an initiator containing a lithium cation, e.g. lithium carbanion or lithium alkoxide, (B) in the presence of a chelate compound having plural tertiary amino groups, e.g. tetramethylethylenediamine which can coordinate the lithium cation and (C) in a polar organic solvent of an ether, e.g. tetrahydrofuran. The polymerization is preferably carried out in an inert gas atmosphere or under reduced pressure at -30 to 100 deg.C (especially 0-50 deg.C) for 1-24hr.