| 摘要: | 本研究係探討界面聚合法製備油性聚氨酯(PU)包覆正二十烷(n-Eicosane)及正二十二烷(n-Docosane)混合並包覆成相轉移材料微膠囊。相變化材料特性穩定，但其不同碳數的相變化材料有固定的相變化溫度。為了能控制其吸放熱溫度及熱焓質，本研究嘗試在極端溫度(約200℃、-5℃)以不破壞相轉移材料的情況下，使用不同比例混合改質正烷類相轉移材料，嘗試改變烷類之熱焓質與吸放熱溫度。
研究中採用掃描式電子顯微鏡、傅立葉轉換紅外線光譜儀、雷射粒徑分析儀、熱重分析儀、熱差分析儀進行結構鑑定佐證與分析，根據分析結果顯示，相變化微膠囊具有平整光滑之表面且成形性良好，在製備條件1000 rpm下所製得之微膠囊的平均粒徑為55.26±1.31μm。
由分析測試結果得知，混和改質後之正烷類中，正二十烷及正二十二烷之混和比例以1：4具最佳效果，起始吸熱溫度與起始放熱溫度會因比例的不同而有所改變，添加多碳數PCM(Phase Change Materials)比例越高時，其起始吸熱溫度與起始放熱溫度會偏向多碳數PCM之溫度。反之，添加少碳數PCM比例越高時，其起始吸熱溫度與起始放熱溫度會偏向少碳數PCM之溫度，經改質後各比例之混合PCM均有提升熱焓質之效果，提升由1.9%到10%，改質混合比例以2：1所提升效果最大，達到10%，確實達到預期之效果。混合後之正烷類再經PU包覆，測得PU/正烷類微膠囊依然擁有良好之吸放熱性質，相變化材料並未因經包覆而改變其原本的特性。
This study was to investigate the oil-based polyurethane (PU) coated with eicosane (n-Eicosane) prepared by solvent evaporation method and positive dodecane (n-Docosane) mixed and coated into a phase transfer material microcapsules. Phase change material properties of the stable, but the phase change of the number of different carbon materials have a fixed phase change temperature. In order to control the suction exothermic temperature and enthalpy of quality, this study attempts to extreme temperatures (about 200 ℃, -5 ℃) does not destroy the phase transfer material, the use of different proportions of mixed modified alkanes relative to the transfer material. try changing the enthalpy of alkanes and quality of the suction temperature heat.
Study using scanning electron microscopy, Fourier transform infrared spectroscopy, laser particle size analyzer, thermal gravimetric analysis, differential thermal analysis for the structural identification evidence and analysis to smooth the surface, according to the results of the analysis, the phase change microcapsulesand good formability, the average particle size of microcapsules obtained under the preparation conditions of 1000 rpm is 55.26 ± 1.31μm.
By the analysis of test results, after mixing modification of alkanes, eicosane and Masaji dodecane mixing ratio of 1:4 with the best results, start endothermic temperature and initial exothermic temperature duedifferent proportion may change, add more carbon and the number of PCM (phase change materials) higher the proportion of the initial endothermic temperature and the initial exothermic temperature will favor the more carbon and the number of PCM temperature. Conversely, when you add less carbon number PCM higher the proportion of the initial endothermic temperature and the initial exothermic temperature will favor less carbon number PCM temperature, after modification, the proportion of mixed PCM have raised the quality of the effect of enthalpy to enhance from 1.9% to 10%, modified mixing ratio of 2:1 to enhance the effect of 10% has certainly achieved the desired effect. Mixture of alkanes by the PU coating, the measured PU / alkanes the microcapsule still have good suction exothermic nature of the phase change material has not been by the coating to change its original features. |
