Magnesium hydroxide (Mg(OH)₂) as a traditional environmentally friendly flame‐retardant is widely used in polymer matrix to fabricate engineering materials. Cooling performance is important for engineering materials and can be characterized by solar reflectance and emissivity. However, solar reflectance and emissivity of Mg(OH)₂ are rarely reported. In this work, cooling properties of Mg(OH)₂ were investigated and the samples were prepared by blending a series weight ratios of Mg(OH)₂ with polymer elastomer matrix (styrene‐ethylene‐butylene‐styrene copolymer [SEBS], polypropylene [PP], and processing oil). With the introduction of 150 phr Mg(OH)₂, the solar reflectance enhanced to 47.23%, which is 31.19% higher than the polymer matrix. Simultaneously, the cooling effect of 15°C can be obtained in comparison with the polymer matrix and emissivity enhanced to 0.86. Meanwhile, an introduction of 150 phr Mg(OH)₂ increased the limit oxygen index from 17 to 26 and vertical burning test (UL‐94) attained to V‐0 rating. Thermal behaviors indicate that the composites exist multiple phase structure, where the glass transition temperature of SEBS is −55°C and melt temperature of PP is 153°C. The results show the composites can be used from −30°C to 80°C and satisfy the outdoor use conditions.

中文翻译：

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氢氧化镁作为多功能添加剂对PP / SEBS /油复合材料的高太阳反射率，热发射率和阻燃性的影响

氢氧化镁（Mg（OH）₂）是一种传统的环保阻燃剂，广泛用于聚合物基体中以制造工程材料。冷却性能对工程材料很重要，并且可以通过太阳反射率和发射率来表征。然而，很少报道Mg（OH）_2的太阳反射率和发射率。在这项工作中，研究了Mg（OH）_2的冷却性能，并通过将一系列Mg（OH）_2的重量比与聚合物弹性体基质（苯乙烯-乙烯-丁烯-苯乙烯共聚物[SEBS]，聚丙烯[ PP]，和加工油）。引入150 phr Mg（OH）₂，太阳反射率提高到47.23％，比聚合物基质高31.19％。同时，与聚合物基体相比可以获得15℃的冷却效果，并且发射率提高到0.86。同时，引入150 phr Mg（OH）₂将极限氧指数从17提高到26，并且垂直燃烧测试（UL-94）达到V-0等级。热行为表明复合材料存在多相结构，其中SEBS的玻璃化转变温度为-55°C，PP的熔融温度为153°C。结果表明，该复合材料可在−30°C至80°C的温度范围内使用，并满足户外使用条件。