新型Ag_mCu_nHgI_4可逆热致变色颜料的研究

Study of a New Type Reversible Thermochromic Paint Ag_mCu_nHgI_4

将Cu(NO3 ) 2 和AgNO3 溶液以不同比例同时加入K2 HgI4水溶液中合成了系列AgmCunHgI4(m +n =2 )可逆热致变色颜料。研究发现 :随着Ag和Cu比例的改变 ,颜料变色温度呈现出一定的变化规律 ;当m和n的比例接近 1∶1时 ,变色温度达到最低 35℃ ;降低环境温度 ,可以缩短产品的复色时间 ;差示扫描量热分析 (DSC)图谱中颜料的相变温度与目测变色温度表现出相同的规律性。在分析AgmCunHgI4颜料变色机理的基础上 ,结合晶体微观结构 ,推测得出晶体的微观对称性越低 。

By adding a solution of Cu(NO 3) 2 and a solution of AgNO 3 in different proportions to an aqueous solution of K 2HgI 4 ,a series of reversible thermochromic paints Ag m Cu n HgI 4( m+n =2)were synthesized.It is found that the thermochromic temperature of the products changes regularly with the ratio of Ag to Cu.When the ratio of m ∶ n is near to 1∶1, the paint has the lowest thermochromic temperature of 35 ℃.The phase-change temperature of the paint in DSC spectra exhibits the same rule as the thermochromic temperature.The color-recovering time of the products is reduced when the surrounding temperature is lowered.Based on the color change mechanism of Ag m Cu n HgI 4 and crystal microstructure,it can be inferred that the lower the microcosmic symmetry of the crystal,the lower the color change temperature of the paint.