Use of tocopherol
AssigneeBayer Shering Pharma AG
InventorsEmilia Tiitinen, Harri Jukarainen
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Abstract
The present invention relates to the use of tocopherol as a co-catalyst in the ring opening polymerisation of cyclic siloxanes. The present invention further relates to a method for manufacturing hydrophilic polysiloxanes, wherein a hydrido-containing cyclic siloxane is reacted with a hydrophilic molecule comprising a carbon-carbon double bond, having the general formula (I) H2C═CH—(CHR)n—O—(CHR1CR2R3)mR4 or (II) H2C═CH—(CHR)n—R5, wherein n is an integer from 0 to 4, m is an integer from 0 to 5, R, R1, R2, R3 and R4 are each independently hydrogen or a C1 to C6 alkyl, R5 is a saturated cyclic hydrocarbon containing carbonyl group, in the presence of a first catalyst to obtain a monomer, and polymerising said monomer in the presence of a second catalyst and tocopherol as a co-catalyst.
Claims3
A method for manufacturing hydrophilic polysiloxanes, wherein a hydrido-containing cyclic siloxane is reacted with a hydrophilic molecule comprising a carbon-carbon double bond, having the general formula (I) or (II)
- H2C═CH—(CHR)n—O—(CHR1CR2R3)mR4 (I)
- H2C═CH—(CHR)n—R5 (II)
- wherein n is an integer from 0 to 4, m is an integer from 0 to 5, R, R1, R2, R3 and R4 are each independently hydrogen or a C1 to C6 alkyl, R5 is a saturated cyclic hydrocarbon containing carbonyl group, in the presence of a first catalyst to obtain a monomer, and polymerising said monomer in the presence of a second catalyst and tocopherol as a co-catalyst.
A method for manufacturing a hydrophilic siloxane elastomer, wherein a hydrido-containing cyclic siloxane is reacted with a hydrophilic molecule comprising a carbon-carbon double bond, having the general formula (I) or (II)
- H2C═CH—(CHR)n—O—(CHR1CR2R3)mR4 (I)
- H2C═CH—(CHR)n—R5 (II)
- wherein n is an integer from 0 to 4, m is an integer from 0 to 5, R, R1, R2, R3 and R4 are each independently hydrogen or a C1 to C6 alkyl, R5 is a saturated cyclic hydrocarbon containing carbonyl group, in the presence of a first catalyst to obtain a monomer,
- polymerising said monomer in the presence of a second catalyst and tocopherol as a co-catalyst to produce a hydrophilic polysiloxane, and
- cross-linking said polysiloxane in the presence of a cross-linking catalyst selected from the group consisting of peroxide cross-linking catalysts and platinum cross-linking catalysts.
Dependencies are inferred from the claim text.