Copolymerization of ethylene and propylene with polar monomers of the types CH2CH(CH2)nOH (n = 1–12) in order to introduce polar functionality into the resulting polymers is possible in principle if the hydroxyl groups of the polar monomers are masked such that they cannot coordinate to Lewis acidic catalyst sites and prevent η2-alkene coordination. Although the use of hydrolysable ethers of the types CH2CH(CH2)nOR (R = alkyl, silyl; n = 1–12) is a protecting group strategy, which has been investigated somewhat, in fact this approach has not been investigated systematically and little is known of the effectiveness of various R groups in hindering oxygen coordination to e.g. metallocene polymerization catalyst systems. We report here the results (a) of an NMR study of reactions of an archetypal metallocene polymerization catalyst, Cp2ZrMe(μ-Me)B(C6F5)3, with the polar monomers CH2CH(CH2)8OR (R = Me, PhCH2, Ph3C, Me3Si, Ph3Si), all protected versions of the readily available, long chain polar monomer 9-decen-1-ol, and (b) of an investigation of the copolymerization reactions of these same polar monomers with ethylene and propylene catalyzed by the well known rac-C2H4(Ind)2ZrCl2/MAO catalyst system. While increasing the steric requirements of the groups R does decrease the apparent abilities of the ethers to displace [BMe(C6F5)3]− from the [Cp2ZrMe]+ cation, there is no correlation of size of R with the degrees of incorporation of the polar monomers into copolymers of ethylene and propylene. Instead, a heretofore unsuspected role for catalyst activation by the ether linkage is suggested.
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