STABILIZED MATERIAL AND COMPOSITION FOR HIGH-VOLTAGE CABLE INSULATION Russian patent published in 2008 - IPC C08L23/06 C08K5/372 C08K5/14 C08K5/3432 H01B3/44 

FIELD: insulation materials.

SUBSTANCE: invention relates to polyethylene composition for insulation of conductors and cables, which exhibits improved scorching resistance and consists of (i) polyethylene and scorching inhibitor having melting point under atmospheric pressure below 50°C and being compound depicted by general formula I, wherein R¹ represents optionally phenyl-substituted С₁-С₂₀-alkyl, С₂-С₂₀-alkenyl, С₃-С₂₀-alkynyl, С₃-С₉-cycloalkyl, phenyl, or tolyl; R² and R³, independently from each other, represent С₁-С₂₀-alkyl optionally substituted by following substituents: phenyl, one or two hydroxyls, cyano group, formyl, acetyl, and -O-COR⁵; R⁵ represents С₁-С₂₀-alkyl, С₂-С₂₀-alkenyl, С₃-С₂₀-alkynyl, or optionally hydroxyl-substituted С₃-С₉-cycloalkyl; phenyl, 4-chlorophenyl, 2-methoxycarbonylphenyl, p-tolyl, 1,3-benzothiazol-2-yl, -(CHR⁶)nCOOR⁷, or -(CHR⁶)nCONR⁸R⁹, wherein n=1 or 2, R⁶ represents hydrogen atom or С₁-С₆-alkyl; R⁷ С₁-С₂₀-alkyl optionally interrupted with 1-5 O or S atoms, С₅-С₇-cycloalkyl, phenyl, benzyl, or tolyl; R⁸ and R⁹ each represents hydrogen atom or С₁-С₆-alkyl; R⁴ represents hydrogen atom or methyl; and (ii) organic peroxide. Composition may be extruded with minimum preliminary cross-linking, even at sufficient cross-linking rate. Polyethylene composition for insulation of conductors and cables with improved scorching resistance is described, which composition additionally contains an amine selected from group consisting of diphenylamine, 4-tert-butyldiphenylamine, 4-tert-octyldiphenylamine, 4,4'-di-tert-butyldiphenylamine, 2,4,4'-tris-tert-butyldiphenylamine, 4-tert-butyl-4'-tert-octyldiphenylamine, o,o', m,m'- or p,p'-di-tert-octyldiphenylamine, 2,4-di-tert-butyl-4'-tert-octyldiphenylamine, 4.4'-di-tert-octyldiphenylamine, 2,4-di-tert-octyl-4'-tert-butyldiphenylamine. This composition may be extruded with minimum preliminary cross-linking, even at sufficient cross-linking rate. Method for preparing cross-linked polyethylene composition is also disclosed. (I).

EFFECT: enhanced resistance against preliminary vulcanization at simultaneously preserved satisfactory vulcanization rate and density of cross linkages formed.

3 cl, 5 tbl