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Updated: Sep 27, 2025

Efficient Synthesis of Polyfunctionalized Benzenes in Water via Persulfate-promoted Benzannulation of α,β-Unsaturated Compounds and Alkynes
Published on: December 16, 2019
Synthesis of thermally robust benzimidazolone-based wholly aromatic polyketones
Xinming Gu1, Zhipeng Wang2, Honghua Wang2
1Department of Oral Implantology, Hospital of Stomatology, Jilin University Changchun 130021 China zhouym@jlu.edu.cn.
Abstract:
A series of wholly aromatic polyketones bearing benzimidazolone moieties (PK-BI) were synthesized via N-C coupling polycondensation. Calcium carbonate coupled with potassium carbonate was used for the first time to achieve a high molecular weight, with T g of the polymer as high as 299 °C. The polymer structure was confirmed by solid state 13C NMR and FT-IR. The thermal stability of wholly aromatic polyketones with a benzimidazolone unit in the main chain was significantly improved, being higher than those of PEEKs and other amorphous PAEKs, proved by thermogravimetric analysis (TGA) and derivative thermogravimetric (DTG) analysis. The degradation activation energy (E k) values estimated by Flynn-Wall-Ozawa (FWO) and Kissinger methods were 260.33 kJ mol-1 and 282.57 kJ mol-1, respectively, which are higher than those of PEEKs.
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