Preparation And Performance Study Of Composite Phase Change Materials

The present situation of energy question is more and more serious, how to save the energy and raise the energy use which attract people's widespread attention, the research of latent heat stored energy on phase change materials (PCM) has been valued by many countries in the world. The preparation and research of composite phase materials has become a hot spot in the region on thermal storage materials. This research took two organic phase change materials which were stearic acid and paraffin as phase change materials, modified kieselguhr and halloysite as carriers, ethanol as solvention, four kinds of composite phase change materials which were stearic acid/modified kieselguhr composite phase change material,stearic acid/halloysite composite phase change material,paraffin/modified kieselguhr composite phase change material and paraffin/halloysite composite phase change material were prepared by solution intercalated reaction. Phase change temperature and latent heat of the composite phase change materials and the thermal stability of the composite phase change materials were characterized using synthesized thermal analyzer(TG-DSC), the chemical compatibility and microstructure of composite phase change materials were characterized using SEM and FT-IR.The results of the research as follows:1. Stearic acid/modified kieselguhr composite phase change material which could be prepared with good performance. Refer to thermal storage capacity and safety, stearic acid's content in composite material should be controlled within 65%, after many times hot and cold cycles, the change of phase change temperature and phase change latent heat were little, the relationship between stearic acid and modified kieselguhr was gomphosis and there was no chemical reaction; The stearic acid/modified kieselguhr composite phase change material when stearic acid's content was 65%, phase change temperature was 62.2℃, phase change latent heat was 142.87J/g;2. Stearic acid/halloysite composite phase change material which could be prepared with good performance. Refer to thermal storage capacity and safety, stearic acid's content in composite material should be controlled within 70%, after many times hot and cold cycles, the change of phase change temperature and phase change latent heat were little, the relationship between stearic acid and halloysite was gomphosis and there was no chemical reaction; the stearic acid/halloysite composite phase change material when stearic acid's content was 70%, phase change temperature was 61.6℃, phase change latent heat was 165.46J/g.3. Paraffin/modified kieselguhr composite phase change material which could be prepared with good performance. Refer to thermal storage capacity and safety, paraffin's content in composite material should be controlled within 65%, after many times hot and cold cycles, the change of phase change temperature and phase change latent heat were little, the relationship between paraffin and modified kieselguhr was gomphosis and there was no chemical reaction; The paraffin/modified kieselguhr composite phase change material when paraffin's content was 65%, phase change temperature was 53.7℃, phase change latent heat was 142.74J/g;4. Paraffin/halloysite composite phase change material which could be prepared with good performance. Refer to thermal storage capacity and safety, paraffin's content in composite materials should be controlled within 75%, after many times hot and cold cycles, the change of phase change temperature and phase change latent heat were little, the relationship between paraffin and halloysite was gomphosis and there was no chemical reaction; the paraffin/halloysite composite phase change material when paraffin's content was 75%, phase change temperature was 52.8℃, phase change latent heat was 158.63J/g.The innovations of this paper as follows: for the first time take modified kieselguhr and halloysite as carriers of composite phase change material, preparated composite phase change materials which are of good performance, the heat storage capacity is high, after hot and cold cycles the thermal performance is stable.