Thermogravimetric analyzer coupled to a mass spectrometer (TGA-MS) was used to study the thermochemical behavior of eight samples. Two varieties of straw (wheat and barley) and two others of binder (lime and plaster) have employed to design four composites. These composites can be considered as innovative insulation materials for buildings. The thermal degradation of the different specimens was studied from a temperature of 50 to 1000ºC using increased temperature of 20ºC/min. This thermal degradation is an important element to evaluate the fire behavior and predict the evolution of smoke emitted during an accidental fire for building application. Using MS analyzer, the ion currents evolutions of 16 molecule groups (shared by a m/z ratio) were followed as functions of temperature. TG curves show that the thermal decomposition of composite samples is more complex (3-4 mass loss steps) than the one of the basic materials (1-2 mass loss stages) and seems to be mostly affected by the binder nature. The highest amount of gas in pyrolysis products is associated to m/z=28 ratio and presents more than two thirds of the total quantity. The kinetic parameters were evaluated for the more important mass loss of each sample and their values are in the ranges of 8.29-64.86 kJ/mol, 0.4-3.36 and 1.78 x 10^3 -1.63 x 10^7 min^-1 for respectively the activation energy, the reaction order and the pre-exponential factor.
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机译：使用热重分析仪与质谱仪（TGA-MS）耦合来研究八个样品的热化学行为。已使用两种稻草（小麦和大麦）和另外两种粘合剂（石灰和灰泥）设计了四种复合材料。这些复合材料可被视为建筑物的创新隔热材料。使用20ºC/ min的升高温度研究了从50到1000ºC的温度下不同样品的热降解。这种热降解是评估火灾行为和预测在建筑应用中发生意外火灾期间散发的烟雾的重要因素。使用MS分析仪，追踪了16个分子组（以m / z比率共享）的离子电流随温度的变化。 TG曲线表明，复合材料样品的热分解（3-4个质量损失步骤）比基本材料之一（1-2个质量损失阶段）更复杂，并且似乎主要受粘合剂性质的影响。热解产物中气体的最高含量与m / z = 28的比例相关，占总量的三分之二以上。针对每个样品的更重要的质量损失评估了动力学参数，其动力学参数分别在8.29-64.86 kJ / mol，0.4-3.36和1.78 x 10 ^ 3 -1.63 x 10 ^ 7 min ^ -1的范围内活化能，反应阶数和指数前因子。
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