Precise characterization of thermal conductivity and interfacial thermal resistance of individual polymer microparticle.

• An H-type measurement device was used for the thermophysical characterization of single microparticles. • The interfacial thermal resistance between single microparticles was analyzed by analytical thermal resistance model. • The effects of temperature and size on the heat transfer performance of microparticles were studied. • The uncertainty of the whole experimental system is about 4.4 %. With the incorporation of microparticles in composite materials becoming increasingly widespread, it is important to study the effect of the thermophysical properties and thermal contact between individual microparticles on heat transfer in composite materials. However, studies on the heat transfer performance of single microparticles are scarce, mainly because the micrometre scale size makes the measurement difficult. Furthermore, the area of contact between microparticles is smaller than the micrometre scale, further enhancing the difficulty of heat measurements. In this study, an H-type measurement device was developed for the thermophysical characterization of single microparticles. Through experimental and theoretical analyses, we obtained the thermal conductivity and thermal resistance of single microparticles of silicon dioxide, polyethylene (PE), poly ether ketone (PEEK) and polymethyl methacrylate (PMMA), apart from the interfacial thermal resistance between two PMMA particles. Furthermore, effective experimental methods were also developed for the study of the heat transfer mechanism of composite materials at the microscopic level. [ABSTRACT FROM AUTHOR]