Xi Xuedong, Pizzi Antonio, Lei Hong, Du Guanben, Zhou Xiaojian, Lin Yuying
Yunnan key laboratory of wood adhesives and glue products, Southwest Forestry University, Kunming 650224, China.
ENSTIB-LERMAB, University of Lorraine, 27 rue Philippe Seguin, 88000 Epinal, France.
Polymers (Basel). 2020 Mar 20;12(3):692. doi: 10.3390/polym12030692.
Synthetic foams have become an essential industrial product for a great variety of applications. Furfuryl alcohol, as a biomass chemical, was reacted with glyoxal at room temperature to prepare furanic-glyoxal rigid foams, and p-toluenesulfonic acid was used as a catalyst to initiate the reaction. Foams with different molar ratios (furfuryl alcohol/glyoxal) were prepared in this work, and uniform cells foams have been obtained. Their compression resistance, 24-h water absorption, density, and other basic properties were tested. Scanning electron microscopy (SEM) was used to observe the cellular morphology of the foams prepared, thermogravimetric analysis (TGA) helped to understand their thermal and combustion properties, and FTIR and Matrix Assisted Laser Desorption Ionisation Time of Flight (MALDI ToF) mass spectroscopy to explain the structure of the resulting foams to clarify the reactions occurring during foaming. The results show that the compression resistance of furanic-glyoxal foams declined as the furfuryl alcohol/glyoxal ratio decreases also. SEM observations revealed that foams with open-cell were obtained when furfuryl alcohol was added in greater amounts, and more closed cell structures were formed as the proportion of glyoxal increased. TGA results showed that the initial ignition temperature of furanic-glyoxal foams is ~200 °C higher than that of wood, and the smaller comprehensive combustion index S (about 0.15 × 10 (% K min)) indicates that the foam burns slowly and has poor flammability, that is, it is not easy to burn.
合成泡沫已成为用于多种应用的重要工业产品。糠醇作为一种生物质化学品，在室温下与乙二醛反应制备呋喃 - 乙二醛硬质泡沫，并使用对甲苯磺酸作为催化剂引发反应。在这项工作中制备了具有不同摩尔比（糠醇/乙二醛）的泡沫，并获得了泡孔均匀的泡沫。测试了它们的抗压性、24小时吸水率、密度和其他基本性能。使用扫描电子显微镜（SEM）观察所制备泡沫的泡孔形态，热重分析（TGA）有助于了解它们的热性能和燃烧性能，傅里叶变换红外光谱（FTIR）和基质辅助激光解吸电离飞行时间（MALDI ToF）质谱用于解释所得泡沫的结构，以阐明发泡过程中发生的反应。结果表明，呋喃 - 乙二醛泡沫的抗压性也随着糠醇/乙二醛比例的降低而下降。SEM观察表明，当糠醇添加量较大时获得了开孔泡沫泡孔，并且随着乙二醛比例的增加形成了更多的闭孔结构。TGA结果表明，呋喃 - 乙二醛泡沫的初始着火温度比木材高约200°C，较小的综合燃烧指数S（约0.15×10（%K min））表明该泡沫燃烧缓慢且易燃性差，即不易燃烧。
