| People are always seeking for smart clothes of thermostat function. Phase change material was used to produce smart thermostat fabric. Phase change material store and release energy based on its own phase change within a certain temperature range which could achieve the storage and release of heat, ambient temperature control and other purposes.The encapsulation of phase change material was the conventiaonal method which expanded the phase change material application in many field, especially in the textile and garment field.In this dissertation, the microcapsules were prepared by Sol-gel method. At the same time, the in-situ polymerized microcapsules were modified by Sol-gel. The core and wall material of the former was paraffin and TEOS respectively. The effect caused by core-wall material ratio, pH and experimental temperature was discussed. The latter was prepared with the core of paraffin and wall of trimethylol melamine, and Sol-gel method was used to modify the in-situ polymerized microcapsulesFrom the infrared spectra, it could be fond there are characteristic peaks for all raw material such as paraffin and silica. The melting temperature and molten phase change heat were tested by Differential scanning calorimetry (DSC). It showed that the melting temperature and molten phase change heat of Sol-gel method, in-situ polymerization and Sol-gel modification method are 57.4? and 80.8J/g,58.0? and 55.0?,60.5J/g and 52.9.1/g. The scanning electron microscope (SEM) images showed microcapsules by Sol-gel method were uniform dispersed with spherical particles. Microcapsules by in-situ polymerization were spherical particles of uniform size. The particle surface was rough, but no adhesion phenomena. The grain of modificated microcapsules was spherical and smooth with reunion. The particle size obtained by a laser particle size analyzer (Ls13320) showed that the mean particle sizes of microcapsules were ranged from 1.7?m to 95.0?m. While the mean microcapsules particle size of situ polymerization was 5.896?m. The mean microcapsule particle size modificated by Sol-gel method was 62.7?m. From the analysis results, the influences sequence of micorcapsules were the core-wall material ratio, pH and experimental temperature. The optimal solution of experiments was the mass ratio of TEOS and paraffin was 1:1, pH of the reaction system was 2.3 and the reaction temperature was 70.0?.Chosen the best from the Sol-gel prepared and Sol-gel modified microcapsules. They were treated on the cotton fabric by padding. The test results showed weight gain, warmth retention, clo value all increased with the content of microcapsules in finishing liquors. Their thermal conductivity, permeability and water vapor permeability dropped. It was found the fabric thermal effect reached the best function when the microcapsules was 15%. The insulation rates were 20.6% and 41.68%. The thermal conductivity were 23.3 W/m2·K and 14.5 W/m2·K, and the col values were 0.28Clo and 0.44Clo.The warm ability of finished fabric was better than the before.Finally, the transfer model of fabric heat and moisture was introduced. And we also set up a mathematical model. This model explained the relationship between the quantity of microcapsules and thermoregulator effect. It could be used to calculate the amount of microcapsules for the designed temperature in actual production. |
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