| 摘要 |
PROBLEM TO BE SOLVED: To obtain a high-melting and low-density polyethylene resin retaining good molding processability, high transparency, flexibility and chemical resistance essential to a polyethylene resin produced by a high-pressure radical polymerization method and improved in heat resistance. SOLUTION: This resin is produced by a high-pressure radical polymerization method and has a densityρ(g/cm<3> ) within the range of 0.910<=ρ<=0.930, a melt index MI (g/10 min) within the range of 0.01<=MI<=300, the number of short- chain branches Sb (number of methyl groups/1,000 carbon atoms) within the range of 5<=Sb<=60 and a melting point Tm ( deg.C) within the range of 118.5-0.370×Sb<=Tm<=118.5-0.170×Sb. The composition contains the resin. The molded product (a power cable insulating layer or a coaxial cable expanded layer, or the like.) is obtained from the resin or the composition. The method for producing the resin comprises polymerizing ethylene under a high reactional pressure (100-400 MPa) at a low polymerization peak temperature (180-320 deg.C).
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