Initiation efficiency of anionic living polymerization of macromonomers

(p-Isopropenylphenethyl)poly (alpha -methylstyrene) macromonomer(PMSM) was polymerized with n-butyllithium (n-BuLi) n-BuLi at -78 degreesC under high vacuum by an anionic living mechanism to yield (PMSM) N star polymers having PMSM as arms. Eight initiation efficiencies (fi) determined under different polymerization conditions scattered in a range of 0.02 to 0.70. In case of fi values above 0.37, a part of initiator was killed by the impurities attached to the inside surface of polymerization glass apparatus (I-im(G) = 5.5 x 10(-5) mol) and by those contained in PMSM (I-im (PMSM) = 5.4 x 10(-5) mol . g(-1)). In case of fi values below 0.10, most of initiator appears to be killed. Taking into account the I-im(G) and I-im (PMSM) values, the molecular design using macromonomers appears to be successfully carried out.