Heat Storage Performance of Disodium Hydrogen Phosphate Dodecahydrate: Prevention of Phase Separation by Thickening and Gelling Methods

• 来源期刊: 中国化学（英文版）
• 年，卷（期）: 2007,（7）
• 页码范围: 921-925
• 页数: 5页
• 语种: 英文

摘要

Disodium hydrogen phosphate dodecahydrate (Na2HPO4·12H2O) is an attractive candidate for phase change materials. The main problem for its practical use comes from incongruent melting character during thermal cycling.Additives such as thickening agent or in-situ synthesized polyacrylate sodium in the molten salt can prevent its phase separation to some extent. In the test, sodium alginate 3.0%-5.0% (w/w) thickened mixture containing Optimum conditions composed of sodium acrylate 3.0%-5.0% (w/w), cross-linking agent N,N-methylenebisparticles dispersed in the gel network at room temperature, commonly less than 2 mm. But only those sample particles with sizes less than 0.2 mm may have relatively stable thermal storage property. A problem encountered was the poor reproducibility of the synthesis method: heat storage capacity of the product was often very different even though the synthesis was carried out in the same conditions. An alternative gelling method by sodium alginate grafted sodium acrylate was tried and it showed a fairly good effect. Heat capacities and heat of fusion of