POLYMERISATION OF SILOXANES

• Main Authors: HUPFIELD PETER C, TAYLOR RICHARD G, MOLONEY GRAINNE M, SURGENOR AVRIL E
• Format: Patent
• Language: English
• Published: 25.07.2000
• Edition: 7
• Subjects: 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

PURPOSE: A polymerisation of siloxanes catalysed by certain phosphazene bases, and in particular a formation of polymeric siloxanes having amino-functionality, is provided. CONSTITUTION: A polymerisation process comprises mixing siloxane polymers with organosilicon compounds having at least one silicon-bonded group R, which is a substituent comprising at least one amine group, and with a phosphazene base catalyst and allowing the siloxanes and organosilicon compounds to polymerise to form amino-functional polyorganosiloxane polymers is claimed. Preferably the phosphazene base is selected from the following formulae: or in which R1 is hydrogen or an optionally substituted hydrocarbon group, or in which two R1 groups bonded to the same N atom may be linked to complete a heterocyclic ring, R2 is hydrogen or an optionally substituted hydrocarbon group, x is 1, 2 or 3; y is 1, 2, 3 or 4, n is an integer with a value of from 1 to 10 and A is an anion.