NEW MODIFIED SILICON OIL FOR LOW TEMPERATURE CURE DIE CASTING LUBRICANTS

摘要

The present invention relates to a mixture of polyalkylsiloxanes that cure at comparably low temperatures of about 170°C while being unreactive under ambient conditions during storage or transport and which are obtainable through a hydrosilylation reaction wherein a mixture of ethylenically unsaturated olefins consisting of 1-100 % of one or more polyene(s) having one terminal double bond which is either monosubstituted or geminal disubstituted and one or more tri- or tetrasubstituted double bond(s), wherein said terminal double bond and said one or more tri- or tetrasubstituted double bond(s) are preferably non-conjugated, and 0-99 mol % of monounsaturated olefins with 6 to 15 carbon atoms is reacted with an amount of one or more polyalkylhydrosiloxanes in the presence of a hydrosilylation catalyst. Furthermore, the present invention relates to water-based compositions suitable for use in metal casting processes as a mold release agent comprising a mixture of polyalkylsiloxanes of the invention and a non-ionic surfactant having a HLB value of at least 8. In addition, the present invention relates to the use of the polyalkylsiloxanes and mixtures of polyalkylsiloxanes as defined herein.