Effect of Borate Cocatalysts toward Activity and Comonomer Incorporation in Ethylene Copolymerization by Half-Titanocene Catalysts in Methylcyclohexane.

Ethylene copolymerizations with 2-methyl-1-pentene, 1-dodecene (DD), vinylcyclohexane (VCH), [Me 2 Si(C 5 Me 4 )(N t Bu)]TiCl 2 ( 1 ), Cp*TiMe 2 (O-2,6- i Pr 2 -4-RC 6 H 2 ) [R = H ( 2 ), SiEt 3 ( 3 )]-borate, and [A(H)] + [BAr 4 ] - [Ar = C 6 F 5 ; A(H) + = N + (H)Me( n -C 18 H 37 ) 2 , N + (H)(CH 2 CF 3 )( n -C 18 H 37 ) 2 , HO + ( n -C 14 H 29 ) 2 ·O( n -C 14 H 29 ) 2 , HO + ( n -C 16 H 33 ) 2 ·O( n -C 16 H 33 ) 2 ; Ar = C 10 F 7 , A(H) + = HO + ( n -C 14 H 29 ) 2 ·O( n -C 14 H 29 ) 2 ( B5 ), N + (H)(CH 2 CF 3 )( n -C 18 H 37 ) 2 ] catalyst systems conducted in methylcyclohexane (MCH) exhibited better comonomer incorporation than those conducted in toluene (in the presence of methylaluminoxane (MAO) or borate cocatalysts). The activity was affected by the borate cocatalyst and 1 , 3 - B5 catalyst systems in MCH and showed the highest activity in the ethylene copolymerizations with VCH and DD.