Poriferous PVC materials with high daytime radiation cooling property fabricated by etching SBS as template

In this study, poriferous PVC slices were prepared by etching SBS in PVC/SBS composites. The porosity increases slightly and the average pore size decreases with the increase of SBS mass fraction. With the increase of porosity, the thermal conductivity of sample E40 w% decreases by 46% from that of PVC. Although the small pores lead to relatively low scattering efficiency, the solar radiation reflectance of sample E40 w% is still high of 85.3%. The ultimate temperature of sample E40 w% is 3.3 °C lower than the average ambient temperature in outside cooling effect test. These results show that using polymer matrix poriferous materials is an effective daytime radiation passive cooling strategy.