Thermal conductivity of ethylene-vinyl acetate copolymers with different vinyl acetate contents dependent on temperature and crystallinity

In this work, the thermal conductivity of a series of ethylene-vinyl acetate copolymers (EVAs) with different vinyl acetate (VAc) contents at different temperatures are measured by the transient hot line method. It is found that the thermal conductivity of a series of EVA samples with different VAc contents decreased smoothly with increasing temperature at temperatures from -20 to 80 degrees C. Meanwhile, the crystallinity and melting point of a series of EVA samples are determined by differential scanning calorimetry (DSC), and an empirical formula between the thermal conductivity of EVA and temperature and crystallinity is established by using a data-fitting method. The theoretical calculation of thermal conductivity obtained from this empirical formula is compared with the measured results, and the error is within 5%. Therefore, this empirical formula is for guidance for predicting the thermal conductivity of EVA samples with different VAc contents at different temperatures in the future.