Phase change materials solid-liquid

Beginn U (2003), Applicability of frozen gels from ultra high molecular weight polyethylene and paraffin waxes as shape persistent solid/liquid phase change materials, Macromolecular Materials and Engineering, 288(3), pp. 245-251. 

Ye H and Ge XS (2000), Preparation of polyethylene-paraffin compound as a form-stable solid-liquid phase change material, Solar Energy Materials and... 

Sari A (2004) Form-stable paraffin/high density polyethylene composites as solid-liquid phase change material for thermal energy storage preparation and thermal properties. Energy Convers Manage 45(13-14) 2033-2042. doi 10.1016/j.enconman.2003.10.022... 

Phase-change material technology utilizes encapsulated latent heat storage units, the core of which can absorb or emit heat when it changes from the solid to the liquid state and vice versa (Figure 60.21). 

For sports that have intermittent exposure to heat and cold, thermal buffers may be appropriate (Shim et ah, 2001). Some ski jackets are equipped with phase change materials that absorb body heat when liquidized and transfer heat to the body when the materials become solid. Although the effects are currently minimal in magnitude for a certain weight, new materials may have better cooling properties (Mondal, 2008). 

McCaim et al. recently introduced an approach that combined the process of melt co-axial electrospinning to encapsulate the phase change materials (PCMs) into polymer or composite sheath. PCM can help stabilize the temperature near its melting point as the material changes the state from a solid to liquid or vice versa and the enthalpy of fusion involved can absorb or release thermal energy. The nanofibers produced using such a material can be used in thermal insulation applications. The researchers used three PCMs, octadecane, hexadecane and eicosane, in melt forms as core solutions and demonstrated temperature stabilization at three different points, 17°C, 30°C and 37°C, respectively ... 

The choice of material was restricted to those having first-order solid-state phase changes in the appropriate temperature ranges. Melting points were excluded because several types of specimen holders in common use could not retain liquids. A number of recognized melting point Standards (e.g. Pb, Zn) may contaminate thermocouples and sample holders through alloy formation, and decomposition processes were considered to be unsuitable because the atmosphere could not be controlled in many types of apparatus. 

Latent heat-storage materials are also called phase change materials (PCM). PCM can absorb or release heat with a slight temperature change. PCM may be repeatedly converted between solid and liquid phases to utilize their latent heat of fusion to absorb, store and release heat or cold during such phase conversions. The latent heats of fusion are greater than the sensible heat capacities of the materials. 

Phase change materials are thermal storage materials that are used to regulate temperature fluctuations. The thermal energy transfer occurs when a material changes fi-om a solid to a hquid or from a liquid to a solid. This is called a change in state, or phase. 

Incorporating microcapsules of PCM into textile structures improves the thermal performance of the textiles. Phase change materials store energy when they change from solid to liquid and dissipate it when they... 

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