Synthesis of polybenzoxazine precursors using thiols: Simultaneous thiol-ene and ring-opening reactions


Beyazkilic Z., Kahveci M. Ü. , Aydogan B., Kışkan B., Yağcı Y.

JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY, cilt.50, ss.4029-4036, 2012 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 50 Konu: 19
  • Basım Tarihi: 2012
  • Doi Numarası: 10.1002/pola.26202
  • Dergi Adı: JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
  • Sayfa Sayıları: ss.4029-4036

Özet

A new class of polybenzoxazine precursors of combined molecular structure of benzoxazine in the open and ring form has been developed. Thermally curable benzoxazine networks were obtained by simultaneous photoinduced thiol-ene and Catalytic Opening of the Lateral Benzoxazine Rings by Thiols (COLBERT). The thiol-ene reactions were initiated by photolysis of a free radical photoinitiator, 2, 2-dimethoxy-2-phenyl acetophenone (DMPA), and the competing COLBERT reaction was triggered by thiol compound, 1,2-ethanedithiol, present in the reaction mixture. The extent of reactions was evaluated by conducting experiments both under UV irradiation and in dark using model benzoxazines. The precursor soft films (pre-P(B-ala-DTE)) were prepared by irradiating solutions of diallyl functional benzoxazine (B-ala), 1,2-ethanedithiol and DMPA. The obtained pre-P(B-ala-DTE) films were then cured through thermally activated ring opening reaction of remaining benzoxazine groups yielding a more rigid and tough film. Thermal and mechanical properties of the films were investigated by DSC, DMA and TGA and compared with a typical polybenzoxazine, P(B-ala). (c) 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012