Thermographic Characterisation of Deformation und Fracture of Semicrystalline Polymers as Basis for Constitutive Modelling of the Material Behaviour

在聚合物材料的加工和变形过程中，耗散过程会产生热量，从而改变材料的力学性能。在描述聚合物的力学行为时，这种反馈往往被考虑得不够。本方案的目标是用高空间和时间分辨率的热像技术来检测聚合物在变形和断裂过程中的耗散热，并将这种热与某些分子变形机制相关联。因此，有必要使热像测量系统适应所描述的任务，并开发适当的数据处理。通过局域能量平衡建立了描述材料热行为的模型。结构表征将通过在线SAXS和WAXS、差示扫描量热仪(DSC)和显微镜并行进行。选择非晶态聚合物(聚碳酸酯，PC)和半结晶聚合物(聚对苯二甲酸乙二醇酯(PET))作为模型体系。最后，将结果进行推广，成为材料行为本构模型的一部分。通过这种方式，该项目将为增进对非晶态和半晶态聚合物的材料理解作出重要贡献。

During processing as well as deforming of polymer materials dissipative processes cause heat production, by which the mechanical properties of the materials change. Describing the mechanical behavior of polymers this feed-back is often taken into consideration only to an insufficient extent.The objective target of the present proposal is the detection of dissipative heating of polymers during deformation and fracture by thermography with high space and time resolution and the correlation of this heating to certain molecular deformation mechanisms. Therefore it will be necessary to adapt a thermography measuring system to the described task and to develop a suitable data processing. A model for the description of the thermal behavior will be developed by local energy balancing.The structure characterization will be performed by Online-SAXS and -WAXS, differential scanning calorimetry (DSC) as well as microscopy in parallel.An amorphous polymer (Polycarbonate, PC) as well as a semi-crystalline polymer (Polyethylene terephthalate, PET) were chosen as model systems.Finally, the results shall be generalized and become part of a constitutive model of the materials behavior. By this way the project will deliver essential contributions to improve material understanding of amorphous as well as semi-crystalline polymers.