麦芽糖-三聚氰胺-甲醛共缩聚树脂的热性能分析

摘要

Maltose-Melamine-Formaldehyde ( MMF) resin was synthesized by the main raw materials of malt-ose, melamine and formaldehyde in alkaline condition.The effect of maltose content (Mmal:Mmel)and the cata-lyst on thermal stabilities were studied by Thermal Gravity Analysis ( TGA) .The curing behavior and functional groups of MMF resin were measured by Different Scanning Calorimetry ( DSC ) and Fourier Transform Infrared Spectroscopy ( FT-IR) .The activation energy and model of curing behavior were calculated by Kissinger-Crane-Arrhenius equation.The results showed that MMF resin turned to be a more stable network structure and less ac-tive group after curing reaction.The TGA showed that there would be three stages in the thermal decomposition process of MMF resin.The ammonium chloride could be a good catalyst for MMF to enhance the thermal stability. The curing behavior of MMF resin was an exothermic process and easier for MMF resin in curing reaction as the more heat enthalpy will be released than MF resin.The activation energy value of MMF resin was 72.74 kJ/mol, and the model of curing behavior was dα/dt =4.26 ×1010 ×e72 740/RTp(1 -α)0.93.%麦芽糖-三聚氰胺-甲醛共缩聚( MMF)树脂是以麦芽糖、 三聚氰胺和甲醛为主要原料, 在碱性条件下合成而得. 研究了麦芽糖与三聚氰胺的摩尔比(Mmal:Mmel)以及固化剂对树脂热稳定性能的影响, 利用DSC和FT-IR 对树脂固化行为以及特征官能团的变化进行了测试分析, 并用Kissinger-Crane-Arrhenius方程对MMF树脂固化动力学进行了探讨. 结果表明: (1) MMF树脂固化后形成了稳定的三维网络结构,游离活性基团的数量明显降低; (2) MMF树脂的热分解过程可以分为3 个阶段, 以氯化铵为固化剂引入MMF树脂后, 体系的热稳定性能明显增强, 具有更好的耐久性和热稳定性; (3) MMF树脂的固化为放热过程, 相比MF树脂, MMF树脂固化放热焓值更大, 固化反应更容易进行; (4) MMF树脂样品的表观活化能为72.74 kJ/mol, MMF树脂固化体系的动力学模型为dα/dt =4.26 ×1010 ×e72740/(RTp)(1 -α)0.93 .