Consideration on the Q-e scheme,3

DOI PDF Web Site 参考文献21件
  • Kawabata Nariyoshi
    Department of Synthetic Chemistry Faculty of Engineering Kyoto University
  • Tsuruta Teiji
    Department of Synthetic Chemistry Faculty of Engineering Kyoto University
  • Furukawa Junji
    Department of Synthetic Chemistry Faculty of Engineering Kyoto University

書誌事項

タイトル別名
  • Consideration on the Q-e Scheme. III. Q-e Factors in Ionic Polymerization

この論文をさがす

抄録

The authors have tried to divide the conjugation-stabilization energy between monomer and attacking polymer cation, ECM, and that between monomer and attacking polymer anion, EAM, into four terms by means of the equations ECM=ECoMo+EC+EM++E′CM and EAM=EAoMo+EA+EM−+E′AM, respectively. Here, ECoMo is the stabilization energy between polyethylene cation and ethylene monomer, EC and EM+ are the increments in the stabilization energies of systems of (substituted polyethylene cation–ethylene monomer) and (polyethylene cation–substituted ethylene monomer) with respect to ECoMo as standard. E′CM is the surplus increment in the stabilization energy of the system of substituted polyethylene cation and substituted ethylene monomer. EAoMo, EA, EA, EM− and E′AM have the significance analogous to ECoMo, EC, EM+ and E′CM, respectively. The E′CM values for most cation-monomer pairs have been found to be negligibly small. This result correlates with the experimental findings that the products of r1r2 are nearly equal to unity for all the cationic copolymerization systems investigated so far. The equation, kCM=PC+QM+exp(–eCM+), is assumed to be applicable to cationic polymerization, the e+-terms being, however, negligible for any cation-monomer pair. Here, Pc+ is the reactivity associated with polymer cation, QM+ is the general reactivity term of monomer in cationic polymerization, and e+ is the corrective term characteristic of polymer cation and monomer. On the other hand, the E′AM values were often found to play a large part in EAM. This result is consistent with some experimental findings by Szwarc et al. The relative reactivity value of vinyl monomers toward carbonium ions is considered to be the general reactivity term in cationic polymerization, Q+. A good correspondence of Q+ with EM+ has been observed.

収録刊行物

参考文献 (21)*注記

もっと見る

キーワード

詳細情報 詳細情報について

問題の指摘

ページトップへ