GB910708A - A process for stabilising polyolefins - Google Patents

Abstract

Polyolefins are stabilized by incorporating therein a compound of formula <FORM:0910708/IV(a)/1> wherein R is an aryl radical which may be substituted by a chlorine atom, a nitro group or an alkyl group having 1-4 carbon atoms, R1 and R2 are substituted or unsubstituted hydrocarbon radicals or substituted or unsubstituted amino groups and R2 may also be a sulphonamide, isourea, isothiourea, guanidine, benzthiazyl or amidine radical or R1 and R2 are dialkyl-substituted amino groups wherein the alkyl groups together with the amino nitrogen may form a ring which may also contain an oxygen atom (see Group IV(b)). The compounds can be used in amounts of 0,01 to 10% based on the polyolefin and in conjunction with other stabilizers, carbon black, aluminium powder, fillers and dyes. Specified polyolefins are linear polyethylenes having a density of approximately 0,94 to 0,98 and polypropylenes. Examples of the stabilized polyolefins are described.ALSO:The invention comprises compounds of formula <FORM:0910708/IV (b)/1> wherein R is a phenyl radical which may be substituted by a chlorine atom, a nitro group or an alkyl group containing from 1-4 carbon atoms and R1 and R2 are each a dialkyl-substituted amino group and the alkyl groups together with the amino nitrogen may form a ring which may also contain an oxygen atom. The preparation of these compounds and also of compounds of the above formula wherein R is an aryl radical which may be substituted as defined above, R1 and R2 are additionally hydrocarbon radicals or amino groups which may be substituted and R3 is also a sulphonamide, isourea, isothiourea, guanidine, benzthiazyl or amidine radical and their use to stabilize polyolefins (see Group IV(a)) is described. The compounds are prepared by reacting an appropriate N-halogen-alkali metal sulphonamide with a sulphur compound such as a thiother, sulphenamide, mercaptan, disulphide or diaminomonosulphide. In an example bis(diethylamine) monosulphide is reacted in aqueous acetone with N-chloro-p-chlorophenyl-sulphonamide to give bis(diethylamino)-sulphine-p-chlorophenylsulphonylimine. Many further compounds are specified.