PREPARATION WELL DEFINED POLYMERS BY POLYMER-COUPLING REACTION .6. REACTION OF LIVING POLYSTYRENE WITH POLY(PARA-FLUOROMETHYLSTYRENE) AND ITS STYRENE COPOLYMER

The reaction of living polystyrene with poly(p-fluoromethylstyrene) (P(FMS)) and its styrene copolymers (P(FM-S)) was carried out under various reaction conditions as one of a series of studies on the preparation of well-defined polymers. This reaction involves the grafting reaction, the monomeric termination, and the dimeric termination of living polystyrene, being greatly affected by reaction conditions. For example, the grafting reaction of polystyryllithium (PSt-Li) takes place almost quantitatively in a tetrahydrofuran-benzene medium whereas the monomeric termination of PSt-Li occurred exclusively in benzene. When P(FMS) was used as the backbone polymer, the degree of grafting was dependent on the mole ratio of living ends to fluoromethyl groups ([LE]/[CH2F]) larger than 0.5, and at [LE]/[CH2F] = 1.15 the “grafting density” of P(FMS) went up to 71% though 38% of PSt-Li gave homopolystyrene. In the case of P(FMS-S), however, the degree of grafting was independent of the mole ratio and an amount of homopolystyrene formed was as small as 10% or less. © 1979, American Chemical Society. All rights reserved.