Combination heat stabilizer/lubricant for PVC processing and method for producing the same
AssigneeMorton International, Inc.
InventorsGeorge F. Beekman, Lionel R. Price, Keith A. Mesch
Life of this patent
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Abstract
The preparation of a zinc mercaptoacid ester by the reaction of zinc oxide with the mercaptoacid ester in a wax matrix provides an improved heat stabilizer for halogen-containing polymer compositions. The process obviates the necessity of isolating and transporting the normally very viscous zinc mercaptoacid esters. The zinc mercaptoacid ester/wax matrix is also an expedient medium for the preparation and utilization of calcium stearate as a lubricant in the heat stabilizer composition and the stabilized polymer composition containing it. A paraffin wax is the preferred matrix for the preparation and use of the heat stabilizer and lubricant.
Claims6
A method for the preparation of a zinc mercaptoester comprising heating a mixture of zinc oxide, a mercaptoester having the formula HS-[CH.sub.2 C(.dbd.O)OR].sub.x --(CH.sub.2).sub.y --C(.dbd.O) OR] wherein R is a straight or branched chain saturated or unsaturated alkyl radical having from 1 to 20 carbon atoms, x=0 or 1, y=1 or 2, and y=1 when x=1, and paraffin wax to a temperature at least equal to the melting range of the wax, and removing water as it forms.
A method for making a stabilizer composition for halogen-containing polymers comprising heating a mixture of zinc oxide, a mercaptoester having the formula HS-[CH.sub.2 C(.dbd.O)OR].sub.x --(CH.sub.2).sub.y --C(.dbd.O)OR] wherein R is a straight or branched chain saturated or unsaturated alkyl radical having from 1 to 20 carbon atoms, x=0 or 1, y=1 or 2, and y=1 when x=1, and paraffin wax to a temperature at least equal to the melting range of the wax, removing water as it forms, adding calcium hydroxide and stearing acid and heating the resulting mixture to remove water.
A heat stabilizer composition consisting essentially of a paraffin wax, calcium stearate, and a zinc mercaptoester made by reacting zinc oxide with a mercaptoester having the formula HS--[CH.sub.2 C(.dbd.O)OR].sub.x --(CH.sub.2).sub.y --C(.dbd.O)OR] wherein R is a straight or branched chain saturated or unsaturated alkyl radical having from 1 to 20 carbon atoms, x=0 or 1, y=1 or 2, and y=1 when x=1 in the paraffin wax matrix.
Dependencies are inferred from the claim text.