Stabilisieren von polymeren Homo- oder Copolymerisaten von Alkylenoxyden

摘要

Polyalkylene oxides are stabilized by a mixture of the following compounds: (a) 1 to 5% of a compound of Formula (I) in which R represents an alkyl group of 1 to 18 carbon atoms; (b) 0.1 to 2% by weight of bis-(4 - hydroxy - 3 - t - butyl - 6 - methyl - phenyl)-sulphide; and (c) 0.1 to 2% by weight of a compound of Formula (II) R1-Sn-R2, in which n is 1 to 4, R1 and R2 are alkyl radicals of 8 to 20 carbon atoms or a group of formula -(CH2)mCOOR3, in which m is 1 to 4, and R3/t is an alkyl group of 8 to 20 carbon atoms; each percentage being based on the weight of the polyalkylene oxide. Suitable polyalkylene oxides are those obtained by polymerizing saturated alkylene oxides, halo-substituted epoxides, including epichlorohydrin, cycloaliphatic epoxides or epoxy ethers, including glycidyl ethers, or by copolymerizing saturated epoxides with unsaturated epoxides, e.g. glycidylacrylate. Typical examples of compounds of Formula (I) are 2,4,5-trihydroxyacetophenone, 2,4,5-trihydroxy caprophenone, and 2,4,5 - trihydroxy - phenyl - decyl - ketone. Typical examples of compounds of Formula (II) are di(dodecyl)sulphide, di(octadecyl) trisulphide, thiodipropionic acid octadecyl ether and tetrasulphide (diacetic acid octadecyl ether). The stabilizer may be added as a solid or in a solution. The stabilized polymers may be dissolved or caused to swell, and may be cross-linked. Swelling agents or solvents include: dimethyl formamide, tetramethylene sulphone, dioxan, methanol, benzene, and chlorinated hydrocarbons. Soots, fillers, dyes or pigments, extender oils or lubricants may also be added. The example describes the stabilization of a methanolic solution of a propylene oxide-allylglycidyl ether copolymer, thiourea, silicic acid, zinc oxide, dipentamethylene thiuram tetrasulphide, 2-mercaptobenzothiazole and titanium dioxide with a mixture of 3% of 2,4,5 - trihydroxybutyrophenone, 0.5% of bis (4 - hydroxy - 3 - t - butyl - 6 - methyl - phenyl) sulphide and 0.5% of di (octadecyl) disulphide, the percentages being based on the weight of copolymer. The resulting copolymer was spun and the filaments cross-linked.