Ethylene homopolymers and copolymers
||DD 147187 A3
||Dec 13, 1977
||Mar 25, 1981
In the manuf. of polyethylene [9002-88-4] and C2H4 copolymers by polymn. in a 1st reactor with an organometallic complex catalyst and then in a 2nd reactor with a radical catalyst, unreacted monomers sepd. from the polymer are recycled only to the 2nd reactor to prevent deactivation of the catalyst in the 1st reactor. Thus, C2H4 is polymd. at 475 K/250 MPa in a reactor contg. a suspension of Ti(CH2Ph)4/Al2O3 in paraffin oil and then at 570 K/180 MPa in a 2nd reactor in the presence of bis(2-ethylhexyl) peroxydicarbonate and BzOOCMe3, giving polymer with d. 0.941. Unreacted C2H4 is recycled to the 2nd reactor only.