The Research Of PCM Which Is Base On EVA

This paper researched the manufacturing means of phase change materials (PCM), this PCM uses EVA as matrix and different materials as phase change working material, adopts the mean of molten blend and adds foaming agent manufacture phase change foam material. Many advanced instrument are used to analysis the PCM, such as temperature recorder, polarization microscope, FTIR-ATR, DSC, TGA and so on. The results show that the compound of LA and SA has appropriate phase-transition temperature (29.36℃) and higher enthalpy of phase change (167.69J/g), it suit used for phase change working material. The compound still has good combination property after packed by EVA. For example, mass loss rate is below1.67%, phase-transition temperature is between25℃and30℃, soaking time is between100s and1250s, there is no chemical reaction between the compound and EVA, they are have nice compatibility. The enthalpy of phase change is between137J/g and160J/g; The compound of LA and PEG4000’s soaking time is500s, phase-transition temperature is about35℃, they will form binary eutectic when the quality score reaches60%, the lowest eutectic temperature is35℃, there is no obvious black cross section of extinction in the compound of LA and PEG4000, and the crystallization is small, the infrared spectroscopic analysis show that there is some chemical reaction between LA and PEG4000, their compatibility increase because of the reactant. After the compound packed by EVA, we find that PCM’s function of keep warm is clearer and clearer along with the increase of the compound’s quality score. Phase-transition temperature is about35℃, the EVA can control the PCM’s crystallization to let its amount and size decrease. The infrared spectroscopic analysis show that there is some chemical reaction between EVA and the compound, their compatibility increase because of the reactant. TGA spectrogram analysis show that both EVA and the compound are in the PCM; The phase change foam material which adopts the mean of molten blend and adds foaming agent uses EVA as matrix and LA/PEG4000as phase change working material. It has very good toughness and tensile strength, the density of the phase change foam material which have not stretch is bigger than the stretched. The density of the phase change foam material which use water as medium is bigger than use paraffins and ethanol. The fibre of the phase change foam material still can keep very good shape at80℃, it has nice usability because its surface is very smooth, and the diameter is very uniform.The frothingpercentage of the phase change foam material can reach14.32%, fit the claim of building and wearability.