Stereospecific Polymerization of Methacrylates with Ethylmagnesium Alkoxides

Reactivity of methacrylates in insertion polymerization.

Polymerization of ethylene by complexes [{(P^O)PdMe(L)}] (P^O = κ(2)-(P,O)-2-(2-MeOC(6)H(4))(2)PC(6)H(4)SO(3))) affords homopolyethylene free of any methyl methacrylate (MMA)-derived units, even in the presence of substantial concentrations of MMA. In stoichiometric studies, reactive {(P^O)Pd(Me)L} fragments generated by halide abstraction from [({(P^O)Pd(Me)Cl}μ-Na)(2)] insert MMA in a 1,2- as...

Polymerization of Alkyl Acrylates and Alkyl Methacrylates with Starch

A series of C4-C 12 alkyl acrylates and methacrylates was polymerized with starch by irradiating starch-monomer mixtures with 60CO. Homopolymers were extracted with cyclohexane. The amounts of insoluble versus soluble synthetic polymer in polymerizations run with alkyl acrylates varied less with the chain length of the alkyl substituent than in the polymerizations run with alkyl methacrylates: ...

Stereospecific carbene polymerization with oxygenated Rh(diene) species.

Polymers bearing polar functionalities are important materials, since they exhibit beneficial properties with respect to adhesion, paint/printability and surface properties. Commercial synthesis of these materials is mainly based on radical processes, which (so far) only allow poor control over the stereochemistry of the resulting polymers. 2 ] Stereo-controlled polymerisation generally require...

Highly trans-stereospecific Isoprene Polymerization by Neodymium Borohydrido Catalysts

The Mechanism of Stereoregulation in Free-Radical Polymerization of Bulky Methacrylates

Theoretical calculations are performed to explore the origin of inherent tacticity in bulky methacrylates. Geometries and conformer distributions of monomers and oligomeric propagating radicals are calculated to study the impact of steric bulk and π-stacking interactions on the preferences for meso versus isotactic propagation. Consistent with the previous qualitative analyses by Satoh and Kami...