为克服 Na₂S₂O₃ ·5H₂O 存在的过冷和相分离现象，以 CaSO₄ ·2H₂O、萘酚等为成核剂，并以羧甲基纤维素( CMC) 、活性白土和水溶性石蜡为增稠剂对 Na₂S₂O₃ ·5H₂O 进行改性， 通过步冷曲线和 DSC 分析对改性后的 Na₂S₂O₃ ·5H₂O  蓄/放热性能进行研究．结果表明: CaSO₄ ·2H₂O、 萘酚以及萘酚- NaCl 对 Na₂S₂O₃ ·5H₂O  均有明显改性效果; 对于Na₂S₂O₃ ·5H₂O - CaSO₄ ·2H₂O 体系，增稠剂用量相同时，水溶性石蜡及活性白土的增稠效果优于 CMC; 经 CaSO₄ ·2H₂O 和活性白土体系改性后的 Na₂S₂O₃ ·5H₂O  最高放热温度在 43 ～48℃之间变化，放热时间最长可达 80min 以上，且均可在 27℃以上完成结晶过程并释放热量; 经萘酚- NaCl 体系改性后的 Na₂S₂O₃ ·5H₂O  具有良好的稳定性，经过不同次数吸热/放热循环后的相变温度在 41 ～46 ℃之间变化，放热时间均可维持在 70 min 以上; 改性后的 Na₂S₂O₃ ·5H₂O  相变焓在 150 ～180J/g 之间， 其蓄/放热过程无相分离现象．

In order to overcome its supercooling and phase separation,Na₂S₂O₃ ·5H₂O ,a kind of phase- changematerial,was modified,with CaSO₄ ·2H₂O,naphthol as the nucleating agents,and with carboxymethyl cellulose(CMC),activated clay and solvable paraffin as the thickening agents. Then,the thermal storage/release perfor-mance of the modified Na₂S₂O₃ ·5H₂O  was investigated by using the cooling curve and the DSC analysis.The re-sults indicate that (1) CaSO₄ ·2H₂O,naphthol and naphthol- NaCl all play important role in the modification of Na₂S₂O₃ ·5H₂O ; (2) as compared with CMC，solvable paraffin and activated clay are of higher thickening effi-ciency for Na₂S₂O₃ ·5H₂O - CaSO₄ ·2H₂O with the same dosage of thickening agent; (3) Na₂S₂O₃ ·5H₂O  modi-fied with CaSO₄ ·2H₂O and activated clay achieves the crystallization and releases thermal energy at above 27℃,with the highest exothermic temperature varying from 43 to 48℃ and with an exothermic duration being more than80min; (4) Na₂S₂O₃ ·5H₂O modified with naphthol- NaCl possesses good stability and is of a phase- change tem-perature varying from 41 to 46℃ at different times of heat storing- releasing circulation,and the heat release evenlasts for more than 70 min; and (5) the phase change enthalpy of modified Na₂S₂O₃ ·5H₂O  varies from 150 to180J/g,while no phase separation occurs in the thermal storage/release process.