水性聚氨酯/功能化石墨烯纳米复合材料的非等温结晶动力学

采用差示扫描量热法DSC研究了水性聚氨酯/功能化石墨烯(WPU/FGNs)纳米复合材料的非等温结晶行为,分别采用Ozawa方程、莫志深方程研究复合材料的非等温结晶动力学,并通过Kissinger方程计算了结晶过程中的活化能。 结果表明,石墨烯在复合材料的结晶过程中起到异相成核剂的作用,提高了复合材料的结晶起始温度、峰值温度和结晶速率;增加石墨烯的质量分数,复合材料的结晶维数增加;石墨烯增加至0.3%,复合材料的活化能从-47.74 kJ/mol降低至-53.60 kJ/mol,继续增加石墨烯至1.0%,复合材料的活化能增加至-41.74 kJ/mol。

Non-isothermal Crystallization Kinetics of Waterborne Polyurethane/functionalized Graphene Nanocomposites

The non-isothermal crystallization behavior of waterborne polyurethane/functionalized graphene nanocomposites(WPU/FGNs) was studied by differential scanning calorimetry(DSC). The non-isothermal crystallization kinetics of WPU/FGNs was investigated by Ozawa and Mo equations, and the crystallization activation energies were calculated by Kissinger equation. The results show that FGNs can be used as heterogeneous nucleation agent to increase the onset of crystallization temperature, peak temperature and crystallization rate of WPU during non-isothermal crystallization process of WPU/FGNs. Crystallization dimension of the composites increases with the increase of the mass fraction of FGNs. When the mass fraction of FGNs increases to 0.3%, crystallization activation energy of the composite decreases from -47.74 kJ/mol to -53.60 kJ/mol. When the mass fraction of FGNs is 1.0%, the crystallization activation energy of the composite increases to -41.74 kJ/mol.