Development of a near-infrared reflecting EVA cooling compound with flame retardant property

A high near-infrared (NIR) reflective cooling compound with flame retardant characteristics was fabricated by incorporating antimony trioxide (Sb₂O₃) and decabrominated diphenyl ethane (DBDPE) into ethylene-vinyl acetate copolymer (EVA). The solar reflectivity and cooling capacities of the control sample and EVA compounds with either Sb₂O₃ or DBDPE, and EVA composites embedded with Sb₂O₃ and DBDPE, were evaluated by ultraviolet–visible–near infrared analysis and temperature tests. The effect of Sb₂O₃ and DBDPE on the flammability, thermal behavior, and mechanical properties of EVA copolymer were determined via the UL-94 burning test, limiting oxygen index (LOI), differential scanning calorimetry, thermogravimetric analysis, and tensile and tearing tests. Compared with the glass blank, EVA compound filled with 10 wt% Sb₂O₃ and 30 wt% DBDPE showed a roughly 17.3°C and 38.0°C decrease during sunlight exposure and in indoors, respectively, accompanied by the maximum NIR reflectivity of 68.8% in all as-prepared blends. Moreover, this as-prepared compound met a UL-94 V-0 classification and reached a LOI value of 29.3%. Notably, the singular addition of either Sb₂O₃ or DBDPE improved the cooling capability of EVA but rarely fulfilled the fire retardant demand. In contrast, the incorporation of Sb₂O₃ and DBDPE improved the desirable cooling and flame retardant properties.