Gu Feng, Yang Wenjing, Xiao Guoqing, Wang Haoran, Yang Quan, Cai Zhaosheng, Wang Wangxia, Zhu J Y
School of Chemistry and Chemical Engineering, Yancheng Institute of Technology, Yancheng 224051, China.
School of Chemistry and Chemical Engineering, Yancheng Institute of Technology, Yancheng 224051, China.
Int J Biol Macromol. 2025 Mar;292:139278. doi: 10.1016/j.ijbiomac.2024.139278. Epub 2024 Dec 28.
Improving flame retardancy and mechanical strength of lignin-containing polyurethane is a great challenge. In this study, lignin with favorable reactivity and dispersity was extracted from poplar using acid hydrotrope p-TsOH in EtOH. The extracted acid hydrotrope lignin (AHL) was subsequently functionalized with nitrogen and phosphorus (FHL) and reacted with isocyanate to fabricate a fire-retardant polyurethane (FHL-PU). The resulting FHL-PU exhibited a five-fold increase in fracture toughness and remarkable reprocessability, attributable to the dual cross-linked network formed by dynamic hydrogen bonds and carbamate bonds between AHL and PU. Furthermore, the FHL can effectively prevent the release of heat and smoke through mechanisms like forming a char layer at elevated temperatures, generating non-combustible gases and sequestering free radicals. As a result, the FHL led to a reduction in the peak heat release rate and total heat release of PU from 946.8 kW/m and 86.9 MJ/m to 383.5 kW/m and 28.4 MJ/m, respectively. This acid hydrotrope lignin modified polyurethane, holds tremendous potential for a wide range of practical applications.
提高含木质素聚氨酯的阻燃性和机械强度是一项巨大挑战。在本研究中，使用乙醇中的酸性助溶剂对甲苯磺酸（p-TsOH）从杨树中提取具有良好反应性和分散性的木质素。随后，将提取的酸性助溶剂木质素（AHL）用氮和磷进行功能化（FHL），并与异氰酸酯反应制备阻燃聚氨酯（FHL-PU）。所得的FHL-PU的断裂韧性提高了五倍，且具有显著的可再加工性，这归因于AHL和PU之间通过动态氢键和氨基甲酸酯键形成的双重交联网络。此外，FHL可通过在高温下形成炭层、产生不可燃气体和捕获自由基等机制有效阻止热量和烟雾的释放。结果，FHL使PU的热释放峰值速率和总热释放量分别从946.8kW/m和86.9MJ/m降至383.5kW/m和28.4MJ/m。这种酸性助溶剂木质素改性聚氨酯在广泛的实际应用中具有巨大潜力。
