Phenacyl Ethyl Carbazolium as a Long Wavelength Photoinitiator for Free Radical Polymerization

Kara M., DADASHI-SILAB S., Yagci Y.

MACROMOLECULAR RAPID COMMUNICATIONS, cilt.36, sa.23, ss.2070-2075, 2015 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 36 Sayı: 23
  • Basım Tarihi: 2015
  • Doi Numarası: 10.1002/marc.201500446
  • Dergi Adı: MACROMOLECULAR RAPID COMMUNICATIONS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.2070-2075
  • İstanbul Teknik Üniversitesi Adresli: Evet

Özet

A new phenacyl-type photoinitiator based on ethyl carbazole as a long wavelength photoinitiator is developed for free radical polymerization. Phenacyl ethyl carbazolium hexafluoroantimonate (PECH) photoinitiator is synthesized in a two-step, one-pot manner by quaternizing ethyl carbazole with phenacyl bromide and subsequent ion exchange reaction with potassium hexafluoroantimonate. Under irradiation, PECH tends to undergo homolytic bond cleavage bringing about initiating free radicals. However, as evidenced by cyclic voltammetry and real-time photobleaching studies, formation of initiating cationic species is highly unlikely as the photochemically formed charged carbazole units tend to couple.