Effects of curing on structure and thermal characteristics of polybenzoxazine based on p-nitroaniline

Date

2016-07-01

Author

Orhan Lekesiz, Tuğba
Hacaloğlu, Jale

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Among the polybenzoxazines, nitroaniline based benzoxazine polymers are not popular for which the polymerization process overlaps with the beginning of the thermal degradation. Phenol and p-nitro aniline based benzoxazine monomer was synthesized and polymerized by applying different temperatures and curing periods systematically to investigate the effect of curing program on polymerization mechanisms via direct pyrolysis mass spectrometry, DP-MS technique. In order to get a better insight on the process, low energy DP-MS analysis was also performed and the results showed that the polymerization of nitroaniline based benzoxazine mainly proceed via attack of NCH2 groups to the phenol ring, contrary to the opposing reaction pathways suggested for benzoxazine based on aniline and the radicals generated by elimination of nitroaniline during curing and/or pyrolysis combined to form unsaturated linkages, resulting a very high char yield.

Subject Keywords

Benzoxazine, Polybenzoxazine, Curing, Pyrolysis

URI

https://hdl.handle.net/11511/31485

Journal

POLYMER DEGRADATION AND STABILITY

DOI

https://doi.org/10.1016/j.polymdegradstab.2016.05.012

Collections

Graduate School of Natural and Applied Sciences, Article

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Citation Formats

T. Orhan Lekesiz and J. Hacaloğlu, “Effects of curing on structure and thermal characteristics of polybenzoxazine based on p-nitroaniline,” POLYMER DEGRADATION AND STABILITY, pp. 363–373, 2016, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/31485.