Stability of Propagating Species in Living Cationic Polymerization of Isobutylene

Daniela Held, B. Iván, Axel H E Müller, Feike De Jong, Teun Graafland

Research output: Contribution to journalArticle

19 Citations (Scopus)

Abstract

The stability of living polyisobutylene chains (PIB) obtained by di- and monofunctional initiators in conjunction with TiCl4 coinitiator was investigated under monomer starved conditions (i. e. after 100 % monomer conversion) in the absence and presence of different additives, such as N,N-dimethylacetamide (DMA), 2,6-di-tert-butylpyridine (DtBP), pyridine (Py) and 2,4-dimethylpyridine (DMPy), in CH2Cl2/hexane (40:60 v/v) mixture at -78 °C. Only negligible amounts of chain ends with expected double bonds were formed as verified by 1H NMR, and all the additives, with the exception of DtBP, resulted in constant molecular weights for a period of four hours. However, chain coupling occurred in the presence of DtBP. On the basis of our experimental findings this effect is interpreted by proton abstraction in a reaction between DtBP and propagating chains leading to external double bonds which further react with active chain ends. Molecular weight distribution data indicate that there are differences among the examined nucleophilic compounds in their mode of action during living polymerization of isobutylene.

Original languageEnglish
Pages (from-to)63-74
Number of pages12
JournalACS Symposium Series
Volume665
Publication statusPublished - 1997

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Cationic polymerization
Living polymerization
Monomers
Hexanes
Molecular weight distribution
Hexane
Pyridine
Protons
Molecular weight
Nuclear magnetic resonance
isobutylene
polyisobutylene
2,4-dimethylpyridine
pyridine
titanium tetrachloride
dimethylacetamide

ASJC Scopus subject areas

  • Chemistry(all)

Cite this

Held, D., Iván, B., Müller, A. H. E., De Jong, F., & Graafland, T. (1997). Stability of Propagating Species in Living Cationic Polymerization of Isobutylene. ACS Symposium Series, 665, 63-74.

Stability of Propagating Species in Living Cationic Polymerization of Isobutylene. / Held, Daniela; Iván, B.; Müller, Axel H E; De Jong, Feike; Graafland, Teun.

In: ACS Symposium Series, Vol. 665, 1997, p. 63-74.

Research output: Contribution to journalArticle

Held, D, Iván, B, Müller, AHE, De Jong, F & Graafland, T 1997, 'Stability of Propagating Species in Living Cationic Polymerization of Isobutylene', ACS Symposium Series, vol. 665, pp. 63-74.
Held, Daniela ; Iván, B. ; Müller, Axel H E ; De Jong, Feike ; Graafland, Teun. / Stability of Propagating Species in Living Cationic Polymerization of Isobutylene. In: ACS Symposium Series. 1997 ; Vol. 665. pp. 63-74.
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