Copolymerization of Ethylene with tert-Butylethylene Using Nonbridged Half-Titanocene-Cocatalyst Systems

Abstract

Contents 1. Selected 1 H and 13 C NMR spectra for poly(ethylene-co-t-butylethylene)s prepared by using Cp′TiCl 2 (O-2,6-i Pr 2 C 6 H 3 ) [Cp′ = Cp* (1), t BuC 5 H 4 (2), 1,2,4-Me 3 C 5 H 2 (6)]-MAO catalyst systems. 2. Selected GPC profiles for poly(ethylene-co-t-butylethylene)s prepared by using Cp′TiCl 2 (O-2,6-i Pr 2 C 6 H 3 ) [Cp′ = Cp* (1), t BuC 5 H 4 (2), 1,2,4-Me 3 C 5 H 2 (6)]-MAO catalyst systems. 3. Selected DSC thermograms for poly(ethylene-co-t-butylethylene)s 4. 13 C NMR spectra for poly(1-hexene), poly(1-hexene-co-vinyltrimethylsilane), and poly(vinyltrimethylsilane) prepared by using ( t BuC 5 H 4 )TiCl 2 (O-2,6-i Pr 2 C 6 H 3 ) (2) and CpTiCl 2 (N=C t Bu 2 ) (3)-MAO catalyst systems.

Olefin Polymerization with Half-Metallocene Catalysts

“…More recently, the tert-BuC 5 H 4 analogue (2b) exhibited rather efficient TBE incorporation in the copolymerization, whereas the Cp'-ketimide analogue (3a, b), constrained geometry catalyst (1), Cp 2 ZrCl 2 did not incorporate TBE under the same conditions (Scheme 2.8, Table 2.7) [79]. Effect of both the cyclopentadienyl fragment (Cp') and the anionic donor ligands (Y) in Cp'TiX 2 (Y) plays a crucial role for the successful copolymerization, as seen in the above copolymerization.…”

“…Efficient synthesis of high molecular weight copolymers with uniform compositions could be achieved by adopting 3a, although both the activity and the M n values seemed to decrease upon the increasing VTMS contents. The copolymerization by the constrained geometry catalyst (1) also proceeded efficiently (Copolymerization with a-olefin containing bulky substituents [79]). …”

“…Modified half-titanocenes showed unique characteristics in ethylene copolymerizations (Reviews for nonbridged half-titanocenes [19,20], Ethylene copolymerization with 2-methyl-1-pentene (disubstited a-olefin [78][79][80][82][83][84][85][86][87][88][89][90][91][92][93][94][95]), and it was demonstrated that an efficient catalyst for ethylene polymerization can be modified for efficient catalysts for syndiospecific styrene polymerization by the ligand modification (Cp') ( [42], Copolymerization with styrene with efficient styrene incorporation or in a living manner [90]). Although some M w values were different from those by the trichloride systems, the order in the M w values was similar to that by the trichloride systems [217].…”

“…Many researchers thus focused on designing the catalysts with ''constrained geometry type'' for the above reason (See Reviews for linked halftitanocenes [15][16][17]46]). Scheme 2.2, have been considered as promising candidates for the efficient catalysts (Reviews for cyclic olefin copolymers [9], See Reviews for nonbridged halftitanocenes [18][19][20][40][41][42], Our initial efforts in olefin polymerization and ethylene/a-olefin copolymerization, for example [60][61][62][63][64][65][66][67][68][69][70][71][72][73][74][75][76][77]81]), because these complex catalysts display unique characteristics especially for synthesis of new polymers (See Reviews for nonbridged half-titanocenes [19,20], Ethylene copolymerization with 2-methyl-1-pentene (disubstited a-olefin) [82,83], Copolymerization with aolefin containing bulky substituents [78][79][80], Copolymerization with norbornene [84][85][86][87], Copolymerization with cyclohexene, cyclopentene [88,89], Copolymerization with styrene with efficient...…”

Microstructure of Copolymers of Norbornene Based on Assignments of 13C NMR Spectra: Evolution of a Methodology

“…[41][42][43][44][45] In particular, 4-methylcyclohexene (4-MeCHE) and 1-methylcyclopentene (1-MeCPE) copolymers have been synthesized recently with nonbridged half-titanocenes containing anionic donor ligands of type, Cp'TiX2(Y) (Cp' = cyclopentadienyl group, Y = aryloxo, ketimide, phosphinimide etc.) [46].…”