POLYETHYLENE, METHOD OF PRODUCTION THEREOF, AND METHOD OF MANUFACTURING POLYETHYLENE PRODUCTS Russian patent published in 1998 - IPC

FIELD: polymer production and polymer materials. SUBSTANCE: polyethylene of invention has dustlike appearance and is characterized by intrinsic viscosity at least 4 dl/g and maximum stretch ratio at least and 20, apparent density not higher than 300 kg/cu.m, and contains 50 ppm residual catalyst. Such polymer is produced via polymerization of ethylene or mixture of ethylene with at most 5 mol % of higher olefins in presence of catalyst containing transition metal and having specific surface not higher than 150 sq.m/g, which process is distinguished by that polymerization is carried out at temperature below 80 C and ethylene pressure as high as 0.2 MPa. Dustlike polyethylene is compressed at temperature below its melting point and pressure at least 10 MPa, and a product is then formed which is stretched at temperature at least 100 C. polyethylene products are characterized by rupture strength at least 1.2 GPa and elasticity modulus at least 80 GPa. EFFECT: improved consumer characteristics. 14 cl, 2 tbl