Macromonomers anionic homopolymerization

The anionic homopolymerization of polystyrene macromonomers was carried out successfully. The methacrylic ester sites at the chain end do not require very strong nucleophiles to be initiated diphenylmethylpotassium was used, and the process was carried out at — 70 °C in THF solution24). The products are comparable with those obtained by free-radical polymerization. The molecular weight distribution should be narrower but this cannot be easily checked because these polymer species are highly branched and compact as already mentioned. 

Anionic homopolymerization of poly-THF macromonomers bearing terminal styryl, a-methylstyryl or methacryloyl groups has not been reported so far. 

A macromonomer is a macromolecule with a reactive end group that can be homopolymerized or copolymerized with a small monomer by cationic, anionic, free-radical, or coordination polymerization (macromonomers for step-growth polymerization will not be considered here). The resulting species may be a star-like polymer (homopolymerization of the macromonomer), a comblike polymer (copolymerization with the same monomer), or a graft polymer (copolymerization with a different monomer) in which the branches are the macromonomer chains. 

The ability of anionic polymerization to polymerize macromonomers has been demonstrated. co-(Methacryloyloxy)-PS macromonomers could be homopolymerized anionically to high yield using diphenylmethyl potassium as an initiator. Similar results could be obtained for co-styryl-PS macro monomers. These cylindrical bmsh species served as models for physicochemical studies. The major difficulty of this reaction... 

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