Cross-linked polyethylene having excellent inhibition of sweat-out and insulation properties

A preparation method of a cross-linked polyethylene composition comprising the steps of:

• (i) mixing and processing by extrusion (A) 100 weight part of polyethylene;
• (B) 0.2-0.6 weight part of a mixture of a liquid antioxidant of Formula 1 and a hindered phenol or a thio ester solid antioxidant;
• (C) 0.2-0.9 weight part of polyethylene glycol having a molecular weight of 5,000-70,000;
• and (D) 1-4 weight part of a cross-linking agent;
• and
• (ii) performing a cross-linking of the extrudate obtained step (i) at a higher temperature than the decomposition temperature of the cross-linking agent.
• wherein,
• R1 is C1-20 alkyl substituted or non-substituted with one or more substituents selected from the group consisting of C2-20 alkenyl, C3-20 alkynyl, C5-9 cycloalkyl, phenyl or tolyl,
• R2 and R3 are independently C1-20 alkyl substituted or non-substituted with one or more substituents selected from the group consisting of phenyl, hydroxyl, cyano, formyl, acetyl and —O—COR5,
• R5 is C5-9 cycloalkyl, phenyl, 4-chlorophenyl, 2-methoxycarbonylphenyl, p-tolyl, 1,3-benzthiazole-2-yl, —(CHR6)nCOOR7 or —(CHR6)nCONR8R9 substituted or non-substituted with one or more substituents selected from the group consisting of C1-20 alkyl, C2-20 alkenyl, C3-20 alkynyl and hydroxy,
• n is 1 or 2;
• R6 is H or C1-6 alkyl;
• R7 is C1-20 alkyl, C1-20 alkyl containing 1-5 hetero atoms selected from O or S, C5-9 cycloalkyl, phenyl, benzyl or tolyl;
• R8 and R9 are independently H or C1-6 alkyl;
• R4 is H or methyl.