양방향 전도열전달을 이용한 표면 거칠기에 따른 폴리머 시편의 열물성 측정

Abstract

The polymer material can effectively utilize the excellent mechanical properties depending on the additive, and can realize a wide range of physical properties through the design of the polymer structure. In addition to mechanical properties, it has attracted attention as a material to replace metals because it has advantages such as transparency, conductivity, heat insulation, water resistance, chemical resistance, fire resistance, and mold ability. In order to apply these polymer products to the field, it is necessary to accurately measure thermal properties. Polymer composites have low thermal conductivity and therefore require high measurement sensitivity. In addition, due to the anisotropy, the processing of the sample for measurement should be minimized because variables such as the alignment and agglutination of the additives, the sample size, thickness, and fabrication conditions affect the thermal properties. Existing thermal property measuring device has a limitation that the sample must be processed in accordance with the measuring principle of the measuring device in order to measure the thermal property. The conventional 3ωmethod has a limitation in that the sensor must be deposited directly on the sample. However, the bidirectional 3ωmethod has a high spatial analysis ability as a measurement method by depositing it on an individual substrate. In addition, since the micro heat is used, it is possible to repeatedly use the sample. Therefore, the thermal properties of solid (HDPE) and semi-solid (PDMS) polymer samples were measured using the bidirectional 3ωmethod. The result of the change of contact thermal resistance according to the change of the degree of pressure and surface roughness was derived using the proven sensor. As a result, it was found that the degree of surface roughness affects the result of thermal property measurement, and it is considered that lowering the surface roughness value will be an important variable for accurate and sensitive thermal property measurement of polymer materials in the future.