Polimer kompozitlerin ısıl karakterizasyonu için fototermal radyometri yönteminin incelenmesi

Considering the advances in material technology, determining the thermophysical properties of polymer composites has great importance for engineering design. Among characterization techniques, the photothermal radiometry (PTR) method is a noncontact and nondestructive method utilized to obtain the thermophysical characterization of various materials. The basis of PTR method relies on detecting variations in infrared radiation (IR) emitted by the modulated laser absorption beam from the material surface. Polymer composites are favorable samples for PTR measurements since they have strong IR emissivity that allows obtaining thermal diffusivity at low excitation power and low frequency range. In the scope of the thesis, a specially modified modulated PTR method with a low-frequency operating range and back detection configuration is designed and developed to measure the thermal diffusivity of the polymer composites. The accuracy and validation of the experimental setup are determined. For this purpose, the experimental measurements are compared with the results from the classical PTR method. Finally, the thermal diffusivity of EPDM composites reinforced with carbon black and graphene nanoplatelets fillers and their hybrid combinations are investigated using the developed low frequency PTR method. Based on the results, the synergistic effect of carbon fillers on the thermophysical properties of hybrid polymer composites was investigated.