Lu Jiayi, Cai Boyu, Xu Wendi, Wang Luze, Luo Zhonglin, Wang Biaobing
Jiangsu Key Laboratory of Environmentally Friendly Polymeric Materials, School of Materials Science and Engineering, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Changzhou University, Changzhou 213164, China.
Materials (Basel). 2023 Jan 5;16(2):519. doi: 10.3390/ma16020519.
To endow synergistically epoxy resin (EP) with excellent fire resistance and high optical transparency, a nitrogen-rich DOPO-based derivate (named as FATP) was synthesized and incorporated into EP. It showed that the incorporation of the FATP reduced the fire hazard of the EP, as demonstrated by the fact that the EP/4% FATP blends gained a UL-94 V-0 rating and an LOI value of 35%, with the lowest values of the THR (86.7 MJ/m), the PHRR (1059.3 kW/m), and the TSP (89.6 MJ/m). The presence of the FATP also reduced the thermal stability and the crosslinking density whilst improving the curing reaction and the storage modulus of the EP/FATP blends. The TG-FTIR spectra showed that •HPO/•PO free radicals and some nonflammable gases (HN and NH) were produced during the pyrolysis, and the characterization (SEM, Raman spectroscopy, and XPS) of char residues confirmed that the FATP facilitated the formation of continuous and compact carbon layers of greater graphitization degree. It was thus concluded that the FATP played the flame-retardant roles in both the gas and condensed phases. Furthermore, the FREPs kept almost identical transparency as the pristine EP, and mechanical properties were also slightly enhanced. The FREPs presented in this work show promising applications in the fields of advanced optical technology.
为了协同赋予环氧树脂（EP）优异的耐火性和高光学透明度，合成了一种富氮的基于DOPO的衍生物（命名为FATP）并将其引入EP中。结果表明，FATP的引入降低了EP的火灾危险性，例如EP/4%FATP共混物获得了UL-94 V-0等级和35%的极限氧指数值，热释放总量（THR，86.7 MJ/m）、热释放速率峰值（PHRR，1059.3 kW/m）和总烟释放量（TSP，89.6 MJ/m）均为最低值。FATP的存在还降低了热稳定性和交联密度，同时改善了EP/FATP共混物的固化反应和储能模量。TG-FTIR光谱表明，热解过程中产生了•HPO/•PO自由基和一些不可燃气体（HN和NH），对残炭的表征（SEM、拉曼光谱和XPS）证实FATP促进了更高石墨化程度的连续致密碳层的形成。因此可以得出结论，FATP在气相和凝聚相中均起到阻燃作用。此外，FREPs与原始EP的透明度几乎相同，机械性能也略有提高。本文介绍的FREPs在先进光学技术领域显示出广阔的应用前景。
