| Abstract: | 本研究是利用液中硬化包覆法製備混合粒而用乳化添加非溶劑法製作微膠囊。膜材為乙基纖維素，芯材為海藻酸鈣與硫酸鈉結晶水混合粒。製備混合粒時，以海藻膠濃度3%；5%氯化鈣溶液經由孔徑1.06mm的針頭所製成的平均粒徑為2.48±0.03mm，最佳包覆率為75.7%。製備微膠囊時，選用乙基纖維素濃度15%置於室溫，表面成形時間需要19.6min。若欲加熱縮短其時間，溫度不可超過50℃。完成的微膠囊平均粒徑為6.50±0.50mm。相變材料硫酸鈉結晶水的含量會明顯地影響潛熱釋放／儲存的時間，但乙基纖維素濃度的高低卻不會影響。以乳化添加非溶劑法製備的微膠囊大大地降低了潛熱釋放／儲存的時間，與純粹硫酸鈉結晶水粒子比較相差約9倍之多。
In this study, ethyl cellulose (EC) microcapsules were prepared by a non-solvent added emulsion method. Ethyl cellulose was used as wall material and calcium alginate mixed with phase change material (PCM) was used as core material. In order to investigate the formation, the optimal content of PCM and the latent heat release/absorption of EC microcapsules, the concentration of alginate, calcium chloride and ethyl cellulose were discussed. The results indicated that the particle size was 2.48±0.03mm, and the optimal content is 75.7%, at the conditions of 3% sodium alginate, 5% calcium chloride solution 30ml. The particle size of EC microcapsule was 6.5±0.5mm. The latent heat release/absorption was affected by the amount of Sodium Sulfate, but was not influenced by ethyl cellulose. The time of latent heat release/absorption was strongly decreased by using a non-solvent added emulsion method, which was 9 times less than pure powders of Sodium Sulfate. |
