本研究的目的是找到擁有在固體或液體狀態熱容量增加的相轉移材料混和物。在固相或液相，熱容量的增加可以提高儲熱的部分，可在更寬的溫度範圍內使用，而不是只在熔點或凝固點附近吸收或釋放熱能。我們使用低溫差示掃描量熱法（LT-DSC）測定熔點和平衡狀態，粉末X射線衍射（PXRD）和小角X射線散射（SAXS）測定樣品的奈米結構，溫度軌跡方法測定熱性能。棕櫚酸為一種高級脂肪酸，而莰烯為一種塑晶(Plastic crystal)。1：1莫耳比的棕櫚酸/莰烯混合物形成PA1CA1。通過使用溫度軌跡方法，無水PA1CA1的熱性能是：熔點 = 322.7+0.0 (K)，液態熱含量 = 2.04+0.04 (kJ kg-1 K-1)，固態熱含量 = 2.17+0.06 (kJ kg-1 K-1)，潛熱 = 114.0+1.2(kJ kg-1) 和固態導熱性 = 0.21+0.00 (W m-1 K-1)和含水PA1CA1的熱性能是：熔點 = 324.8+0.2 (K)，液態熱含量 = 2.29+0.04 (kJ kg-1 K-1)，固態熱含量 = 2.61+0.01(kJ kg-1 K-1)，潛熱 =119.6+1.8 (kJ kg-1)，固態導熱性 = 0.21+0.01(W m-1 K-1)。總體而言，含水PA1CA1優於無水PA1CA1，因為含水PA1CA1比無水PA1CA1有較高的固態和液態熱容量增加。部分非晶相的形成(更加無序狀態)，有助於提高固態無水或含水PA1CA1的熱容量。在此研究中的棕櫚酸和莰烯混合物並不是共晶混和物，而是222到431奈米尺寸的棕櫚酸顆粒分散在非晶型莰烯基質中以形成固態分散體(Solid dispersions)。我們的系統可以用在生物氣候建築/結構的被動儲存系統和應用在離峰時段的冷卻和加熱。 Our aim is to find phase change material (PCM) mixtures which also have an increase in the heat capacity in solid or liquid state. Increasing heat capacity in liquid or solid state would enhance the part of heat storage which can be used in a wider temperature range, rather than just to absorb or release heat energy near the melting point or freezing point. We use low-temperature differential scanning calorimetry (LT-DSC) to determine the melting point and the equilibrium state, powder X-ray diffraction (PXRD) and small-angle X-ray scattering (SAXS) to determine the nano structures, temperature-history method to find the thermal properties in large-scale. 1: 1 molar ratios of palmitic acid/camphene mixture (PA1CA1) By using temperature-history method, thermal properties of anhydrous PA1CA1 are: Tm = 322.7+0.0 K, cpl = 2.04+0.04 kJ kg-1 K-1, cps = 2.17+0.06 kJ kg-1 K-1, ΔHls = 114.0+1.2 kJ kg-1, and ks = 0.21+0.00 W m-1 K-1 and the thermal properties of hydrated PA1CA1 are: Tm = 324.8+0.2 K, cpl = 2.29+0.04 kJ kg-1 K-1, cps = 2.61+0.01 kJ kg-1 K-1, ΔHls = 119.6+1.8 kJ kg-1, and ks = 0.21+0.01 W m-1 K-1. Overall, hydrated PA1CA1 is better than anhydrous PA1CA1 with increasing in both heat capacity in solid and liquid state. Partial amorphous phase formation (more disordered state) helps increase the heat capacity in solid state of anhydrous or hydrated PA1CA1. The mixture of palmitic acid and camphene in this research is not a eutectic mixture but rather palmitic acid particles nanometer-sized 222 nm ~431 nm are dispersed in partial amorphous camphene matrix to form a solid dispersion. Our systems can be used in passive storage in bio-climatic building/architecture and application in off-peak electricity for cooling and heating.
