Premium
Polymerization of methyl methacrylate with the neutral zirconocene enolate Cp 2 ZrMe[OC(Me)=CMe 2 ]
Author(s) -
Bandermann Friedhelm,
Ferenz Michael,
Sustmann Reiner,
Sicking Willi
Publication year - 2001
Publication title -
macromolecular symposia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.257
H-Index - 76
eISSN - 1521-3900
pISSN - 1022-1360
DOI - 10.1002/1521-3900(200109)174:1<247::aid-masy247>3.0.co;2-g
Subject(s) - polymerization , methyl methacrylate , polymer chemistry , molar mass distribution , tacticity , chemistry , materials science , polymer , organic chemistry
The polymerization of methyl methacrylate (MMA) with the neutral enolate Cp 2 ZrMe[OC(OMe)=CMe 2 ] in the absence and in the presence of zirconocene cations Cp 2 ZrMe + to bypass the rate‐ limited initiation of the system was investigated. Only by itself the enolate is not active in polymerization, but as soon as the reaction system contains the cation MMA is quantitatively converted into syndiotactic‐rich PMMA with high molecular weight ( M n > 100 000 g mol −1 ) and very narrow molecular weight distribution ( M w / M n < 1.05). The rate of polymerization was found to be first order reffering to the neutral enolate and also reffering to the cation. Rate coefficents of all elementary reactions were determined and compared to those received by the kinetic investigation of the polymerization using the initiator system Cp 2 ZrMe 2 /Ph 3 CB(C 6 F 5 ) 4 . The agreement of both sets of calculated coefficients is satisfying. These results confirm that the mechanism of Collins et al. is suitable to describe the properties of the polymerization process.