Synergistic heat stabilizer compositions containing an antimony or a bismuth compound
AssigneeM&T Chemicals Inc.
InventorRobert D. Dworkin
Life of this patent
Estimating the term…
Abstract
The combination of a conventional antimony--or bismuth-containing heat stabilizers with certain aromatic esters or aryloxides containing boron, phosphorus, silicon, antimony, tin or zinc interacts synergistically to provide an unexpectedly high level of heat stability to halogen-containing polymers such as polyvinyl chloride (PVC). In addition the aromatic ester or aryloxide inhibits spontaneous degradation of the heat stabilizing component in the presence of heat and/or light.
Claims18
In an improved composition for imparting heat stability to halogen-containing polymers of ethylenically unsaturated hydrocarbons wherein the heat stabilizer exhibits the general formula MX.sub.3, MX.sub.n Y.sub.3-n, RM=S and R.sub.n MX.sub.3-n wherein M is antimony or bismuth, R is hydrocarbyl, n is 1 or 2 and X and Y individually represent the residue obtained by removing (1) the hydrogen atom from a carboxy (--COOH) group of a mono- or polyfunctional carboxylic acid or mercaptocarboxylic acid or (2) the hydrogen atom from the sulfur atom of a mercaptan, mercaptoalkanol, mercaptocarboxylic acid or an ester of a mercaptocarboxylic acid or mercaptoalkanol, the improvement which resides in the presence in said composition of a synergist containing at least one residue obtained by removing one or both hydrogens from the hydroxyl groups of a o-dihydric phenol, said residue being bonded through one or both oxygen atoms to an element selected from the group consisting of boron, phosphorus, silicon, antimony, tin and zinc.
Dependencies are inferred from the claim text.