Paraffins are typical organic phase change materials (PCM) used for latent heat storage. For practical applications they must be encapsulated to prevent leakage or agglomeration during fusion. In this study it is shown that eicosane (C₂₀H₄₂ = C20) in the melted state could be dissolved in the hydrophobic domains of poly(dodecyl methacrylate) (PDMA) up to concentrations of 30 wt %, avoiding the need of encapsulation. For a 30 wt % solution, the heat of phase change was close to 69 J/g, a reasonable value for its use as a PCM. The fully converted solution remained transparent at 80 °C with no evidence of phase separation but became opaque by cooling as a consequence of paraffin crystallization. Heating above the melting temperature regenerated a transparent material. A high contrast ratio and abrupt transition between opaque and transparent states was observed for the 30 wt % blends, with a transparent state at 35 °C and an opaque state at 23 °C. This behavior was completely reproducible during consecutive heating/cooling cycles, indicating the possible use of this material as a thermally reversible light scattering (TRLS) film.

中文翻译：

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聚（甲基丙烯酸十二烷基酯）用作相变材料和热可逆光散射膜的石蜡溶剂

石蜡是用于潜热存储的典型有机相变材料（PCM）。对于实际应用，必须将其封装以防止融合过程中发生泄漏或结块。在这项研究中，表明二十烷（C ₂₀ H ₄₂处于熔融状态的C20）可以溶解在聚甲基丙烯酸十二烷基酯（PDMA）的疏水域中，浓度最高为30 wt％，而无需封装。对于30 wt％的溶液，相变热接近69 J / g，对于用作PCM来说是一个合理的值。完全转化的溶液在80°C下保持透明，没有相分离的迹象，但由于石蜡结晶，冷却后变为不透明。加热至高于熔化温度，则产生了透明材料。对于30重量％的共混物，观察到高对比度和不透明状态与透明状态之间的突然转变，其中在35℃下为透明状态而在23℃下为不透明状态。在连续的加热/冷却循环中，这种行为是完全可重现的，