Hongliang Ding, Xin Wang^*, Lei Song, Yuan Hu

Journal of Renewable Materials, Vol.10, No.4, pp. 871-895, 2022, DOI:10.32604/jrm.2022.018150 - 02 November 2021

Abstract Benzoxazines have attracted wide attention from academics all over the world because of their unique properties. However, most of the production and preparation of benzoxazine resins depends on petroleum resources now, especially bisphenol A-based benzoxazine. Therefore, owing to the environmental impacts, the development of bio-based benzoxazines is gaining more and more interest to substitute petroleum-based benzoxazines. Similar to petroleum-based benzoxazines, most of bio-based benzoxazines suffer from flammability. Thus, it is necessary to endow bio-based benzoxazines with outstanding flame retardancy. The purpose of this review is to summarize the latest advance in flame retardant bio-based benzoxazines. More > Graphic Abstract

Rumeng Li¹, Guozhu Zhan², Qi Ma¹, Yunhe Yang¹, Xiaoyun Liu^1,*, Yitong Zhang¹, Qixin Zhuang¹

Journal of Renewable Materials, Vol.9, No.12, pp. 2093-2117, 2021, DOI:10.32604/jrm.2021.015827 - 22 June 2021

Abstract To explore the influence of substituent groups on thermally induced curing, eight new bio-based benzoxazines containing different substituent groups with different electron negativity and volumes were synthesized. The thermal curing of these bio-based benzoxazines was studied in detail. Combined with the curing reaction kinetics, simulation and calculation of Highest Occupied Molecular and Lowest Unoccupied Molecular values, the spatial and electronic effects of different substituent groups on the curing of benzoxazine was explored. It was found that when the substituent was located at the position directly connected to the N atom, the steric hindrance effect of… More > Graphic Abstract

CHUNYAN LIU^*, YUNHE LIU, ZIHAN PAN, QIUTING LI, HAN XU, TAO LIU

Journal of Polymer Materials, Vol.36, No.1, pp. 87-99, 2019, DOI:10.32381/JPM.2019.36.01.7

Abstract In this work, a series of novel lignin-based bis-benzoxazine monomers were efficiently synthesized by the reaction of renewable phenols: guaiacol, vanillyl alcohol, eugenol, vanillin with ethylene diamine and paraformaldehyde. The chemical structures of these lignin-based bis-benzoxazine monomers were confirmed by ¹H-NMR, ¹³C-NMR and FTIR, indicating the formation of benzoxazine ring. The obtained bis-benzoxazine monomers were cured via thermal treatment. The curing behavior of these lignin-based bis-benzoxazine monomers were compared and analyzed via differential scanning calorimetry (DSC), showing that Va-e possessed higher ring-opening polymerization activity than G-e, while E-e and V-e had lower curing activity than G-e. More >