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With the energy and environmental pollution problems are becoming ever more prominent, energy conservation has become one of the main themes of the development of countries. The phase transition of the phase change energy storage technologies use materials absorb, store and release energy, energy supply and demand so as to solve conflicts and to improve the utilization of energy in time and space match. Development of efficient, long-life phase change material (phase change materials, PCMs) is one of the hotspots of energy-saving technologies. The PCMS application process leaks and compatibility with the environment and other issues directly restricts its application. Therefore, PCMs packaging technology is particularly important, the main encapsulation method amorphous and microencapsulation. This article choose good chemical stability, a wide range of sources, inexpensive, green gelatin, gum arabic as a raw material, whichever polymerization reaction of polymer microcapsules of the first floor wall material, polyvinyl alcohol (PVA) is a complex layer membrane wall material, polyol PCMs microencapsulated PCMs microcapsules and prepared performance. In this paper, Span-80 Tween-80 as emulsifier, dodecanol prepared by stir-stable emulsion. Dodecanol droplets in the emulsion and allowed to stand for one month after its size is still consistent with a fresh sample, about 1-4μm. Dodecanol prepared emulsion has a viscosity (298 K, 6.4 mPa · s), high storage density (20.0-40.0 J, · g -1 ) characteristics. In stable emulsions based on gelatin - gum arabic polymer / the PCMS (dodecyl alcohol, cetyl alcohol BS) microcapsules were prepared by a phase separation method, to achieve a single-layer film-coated, Built microcapsules ΔHf 44.7 96.2 J · g -1 , 96.3 J · g -1 , 48.4 J · g -1 , the core material encapsulation efficiency wt%, 46.3 wt%, 45.7 wt%. On this basis, was added in the spray drying process of polyvinyl alcohol (PVA), PVA / gelatin - gum arabic polymer / the PCMS (dodecyl alcohol, cetyl alcohol BS) microcapsules, in order to achieve the double-layer film-coated, The ΔHf microcapsules were 111.6 J · g -1 109.7 J · g -1 61.4 J · g -1 , core material encapsulation efficiency of 51.8 wt%, 52.8 wt%, 57.7 wt%. The results showed that, with respect to a single-layer film-coated PVA Add further improve the dispersibility of the microcapsules, and effectively prevents the loss of the core material, thereby improving the thermal storage density and lifetime of the PCMs.
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