CATALYST FOR THE PREPARATION OF TRANS POLYPENTENAMERS

1296167 Cycloolefin polymerization FARBENFABRIKEN BAYER AG 19 April 1971 [14 Feb 1970] 20674/71 Heading C3P A catalyst for the ring-opening polymerization of cyclomono-olefins comprises (a) the reaction product of a tungsten or tantalum halide with an acetal or ketal and (b) an organometallic compound of a metal of Groups Ia, IIa, IIIb or IVb, preferably aluminium, the molar ratio of the metal in component (a) to that in component (b) being 1 : 0À3 to 1 : 10 for tungsten and 1 : 1 to 1 : 10 for tantalum. Component (a) is soluble in hydrocarbons and halohydrocarbons; it may be prepared by mixing a solution or suspension of the metal halide in one of these solvents with the acetal or ketal. Component (a) is then mixed with component (b), preferably in the presence of the cyclo-olefin monomer. The examples describe the polymerization of cyclopentene to trans-polypentenamer using as component (a) the reaction product of WCl 6 with CH 2 (OCH 2 CH 2 Cl) 2 , CH 2 (OCH 3 ) 2 , CH 3 .CH(OC 2 H 5 ) 2 , Cl 3 C.CH(OCH 3 ) 2 or C 6 H 5 .CH(OC 2 H 5 ) 2 or TaCl 5 with CH 2 (OCH 2 CH 2 Cl) 2 , and as component (b) Et 3 Al, Et 2 AlCl, Et 3 Al 2 Cl 3 or EtAlCl 2 . In some examples butene-1 was also present as a molecular weight regulator.