Thermally curable benzoxazine monomer with a photodimerizable coumarin group


Kiskan B. , Yagci Y.

JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY, vol.45, no.9, pp.1670-1676, 2007 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 45 Issue: 9
  • Publication Date: 2007
  • Doi Number: 10.1002/pola.21934
  • Title of Journal : JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
  • Page Numbers: pp.1670-1676
  • Keywords: benzoxazine, coumarin, crosslinking, photodimerization, thermal ring-opening polymerization, thermosets, NONIONIC HYDROGEL, PHENOLIC RESINS, POLYBENZOXAZINE, POLYMERIZATION, 2-METHYL-2-OXAZOLINE, POLYOXAZOLINE, COPOLYMERS

Abstract

A new monomer, 4-methyl-9-p-tolyl-9,10-dihydrochromeno[8,7-e][1,3]oxazin-2(8H)-one, possessing both benzoxazine and coumarin rings in its structure was synthesized by the reaction of 4-methyl-7-hydroxycoumarin, paraformaldehyde, and p-toluidine in methanol at 40 degrees C and characterized with spectral analysis. Upon photolysis around 300 mm, this monomer underwent dimerization via the [2 pi s+2 pi s] cycloaddition reaction. Photodimerization reactions were investigated with LTV and (1)H NMR spectroscopy measurements. The thermal ring-opening reaction of the benzoxazine ring was demonstrated with differential scanning calorimetry measurements. The thermal behavior of the cured product was also investigated with thermogravimetric analysis. (c) 2007 Wiley Periodicals, Inc.