Publication Date:
2018-02-03
Description:
In this paper, the imidization mechanism of polyamic acid to prepare polyimide has been studied by the density functional theory (DFT) method. Our results have shown that the imidization would proceed via two different reaction paths. The activation barrier via hydrogen transfer to closer carboxylate oxygen in the COOH is 220.35 kJ/mol while the activation barrier via hydrogen transfer to hydroxyl oxygen in the COOH is 220.70 kJ/mol. Both reaction paths would run in the actual thermal imidization process with closer high activation barriers. The high energy barrier interpreted the fact that additional energy or catalyst is usually needed during imidization. Moreover, the intrinsic imidization mechanism indicated is critical to further improve the imidization process.
Print ISSN:
1757-8981
Electronic ISSN:
1757-899X
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
