Aromatic dialdehyde-based bisbenzoxazines: The influence of relative position of oxazine rings

POLYMER

卷:216

Article

Tavernier, Romain¹  Granado, Lerys¹  Foyer, Gabriel²  David, Ghislain¹  Caillol, Sylvain¹ 

[1] Univ Montpellier, ENSCM, CNRS, ICGM, Montpellier, France

[2] ArianeGroup, Rue Touban, F-33185 Le Haillan, France

关键词: Polybenzoxazines;    Isoconversional analysis;    High char yield;    High performance thermoset;   

DOI  :  10.1016/j.polymer.2020.123270

来源: Elsevier

【 摘 要 】

Polybenzoxazines are known to have superior thermal stability. Especially, the use of aromatic aldehydes instead of formaldehyde for the synthesis of benzoxazines monomers could improve this stability. However, the increase in aromatic content of the monomer can prevent the processability. The objective of this article is to understand the relationships between the conformation of an aromatic dialdehyde and its thermal properties. Two benzoxazine monomers were synthesized, based on salicylaldehyde, furfurylamine and respectively terephthalaldehyde (TPA, para configuration) and isophthalaldehyde (IPA, meta). Structural characterizations showed differences in intramolecular interactions between the two isomers. The melting transition of meta isomer was 50 degrees C lower than for para monomer, whereas polymerization temperatures and enthalpies were nearly the same. Volatile compounds released during the polymerization were the same in both cases, as investigated by mass spectrometry (Py-GC/MS). Curing kinetics using model-free kinetic methods revealed that the E-dependency follows the same trend for both monomers. Finally, thermal degradation monitored by thermogravimetric analysis under inert atmosphere was similar, with high degradation temperatures and high char yields (64%).

【 授权许可】

Free