Tao Li, Wen-hao Yang, Yu-wei Zhang, Mao-shan Niu, Ri-wei Xu, Ding-sheng Yu. Synthesis of the p-Propynyloxyphenyl-2-oxazoline(POPO) and Performance of Poly(benzoxazine/POPO)[J]. Acta Polymerica Sinica, 2014,(3):302-308.
A novel difunctional monomer p-propynyloxyphenyl-2-oxazoline(POPO) was synthesized and characterizaed by 1H-NMR
FTIR
GC-MS and elemental analysis.The curing behavior and thermal performance of POPO were explained by DSC and TGA.Consequently
its melt point is 120 ℃
the initial curing temperature(Ti)is 200 ℃ and the cured POPO shows a good thermal stability:the 5 wt% weight loss temperature is 321 ℃
the residual weight is 28 wt% at 900 ℃.Bisphenol A-benzoxazine(BZ)/POPO resins were prepared via solution blending process
and the curing mechanism and thermal properties of the cured BZ/POPO resins were studied.First
the ring-opening reaction of benzoxazine occurred
then the phenolic hydoroxyl groups generated by the ring-opening reaction of benzoxazine rings reacted with oxazoline rings.While
the polymerization reaction of the alkynyl group of POPO happened throughout the whole reaction process.The results of DSC
TGA and DMA analyses showed that the thermal properties and dynamic mechanical properties of the cured BZ/POPO resins were improved respectively for the cross-linking density of the cured BZ/POPO resins was increased.When the mass fraction of the POPO was 10 wt%
the initial curing temperature(Ti)
residual weight and glass transition temperature(Tg) of the cured BZ/POPO resin were 180 ℃
40 wt% and 186 ℃ compared with those of pure bisphenol A-benzoxazine resin (215 ℃
28 wt% and 166 ℃ respectively).POPO is a kind of good modifier for bisphenol A-benzoxazine resin by which the thermal properties and dynamic mechanical properties of the cured BZ resin can be improved to meet the demand of versatile applications.