GB744875A - Improvements in and relating to polythene - Google Patents

Abstract

Polythene is stabilized with a dihydroxyphenol or a normal or basic aluminium, barium, calcium, magnesium, strontium or zinc salt thereof, the phenol having the formula <FORM:0744875/IV(a)/1> in which R1 and R11 are alkyl radicals of 1 to 3 carbon atoms, R2 and R21 are alkyl, cycloalkyl or alkyl substituted cycloalkyl radicals, and R3 is an alkylene radical which may contain side chain alkyl groups. Specified stabilizers are bis - (2 - hydroxy - 3,5 - dimethyl phenyl) methane; bis - (2 - hydroxy - 3 - t - butyl - 5 - methyl phenyl) methane; 1,2 - bis - (2 - hydroxy - 3 - t - butyl - 5 - methyl phenyl) ethane; 1,2 - bis - (2-hydroxy - 3,5 - dimethyl phenyl) ethane; bis-(2 - hydroxy - 3 - t - butyl - 5 - methyl phenyl) dimethyl methane; bis - (2 - hydroxy - 3,5 - dimethyl phenyl) dimethyl methane; and bis-(2 - hydroxy - 3 - 5 - methylcyclohexyl - 5 - methyl phenyl) methane. Optional additives are fillers, other stabilizers, dyes, pigments, waxes and other polymers. Small amounts of stabilizer may be more accurately incorporated in polythene by the use of a master batch containing the stabilizer in much larger amount. The products are substantially free from staining and in examples the electrical and other physical properties of moulded compositions are given. Specifications 571,943, 728,290, [Group IV (b)], and 728,291 are referred to.