高储能性相变微胶囊的可控制备对于相变潜热的高效利用具有重要意义。基于此,利用微流控技术,分别以石蜡和碳纳米管(CNT)复合海藻酸钠为芯材和壳材,通过乳化固化法制备得到了石蜡相变微胶囊,并研究了CNT含量对相变微胶囊性能的影响规律。结果表明:随着壳层中CNT含量的不断增加,微胶囊对石蜡的包封能力显著提高,当其含量为3%时,石蜡相变微胶囊的包封率接近96%,热焓值达206.8J/g。同时,石蜡相变微胶囊的光热转换能力也随CNT含量的增加而增强,并在光照11min后,其温度可达47℃。相关研究结果可为可控制备具有高储能性和光热转换性能的相变微胶囊提供科学指导。
Controllable preparation of phase change microcapsules with high energy storage is of great significance for efficient use of phase change latent heat.Based on this,utilizing microfluidic technology,the paraffin phase change microcapsules were successfully prepared via emulsification-solidification method using paraffin as the core and sodium alginate containing carbon nanotube (CNT) as the shell material,respectively.The effects of the mass fractions of CNT on the performance of phase change microcapsules were studied.The results showed that,the encapsulation efficiency of the microcapsules for paraffin wax significantly improved as the mass fraction of CNT in the shell increased.Specially,when the mass fraction of CNT was 3wt%,the encapsulation efficiency reached up to 96%,and the enthalpy value of the resultant phase change microcapsules was 206.8J/g.Meanwhile,the ability of photothermal conversion of paraffin phase change microcapsules was also enhanced with the increase of CNT mass fraction,and their temperature reached 47℃ after 11min of light exposure.The obtained results could provide a scientific guidance for the controllable preparation of phase change microcapsules with high energy storage and photothermal conversion properties.
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基金资助
国家自然科学基金(22278274和21922809)
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