改性三水合乙酸钠的制备及成核稳定性分析

PREPARATION AND NUCLEATION STABILITY ANALYSIS OF MODIFIED SODIUM ACETATE TRIHYDRATE

针对三水合乙酸钠(SAT)的过冷及相分离的问题,进行其成核与增稠优化改性实验。结果表明:十二水磷酸氢二钠是SAT的有效成核剂,其添加量为2.0%时,可有效抑制SAT的过冷,将过冷度控制在2℃以内。黄原胶可作为SAT的有效增稠剂,其添加量为1.5%时,可有效抑制SAT在融化/凝固循环过程中的相分离。此外,利用电子扫描显微镜(SEM)对所选成核剂进行微观表征,发现成核剂的成核稳定性与其表面形状存在一定关系,成核剂的表面越粗糙、孔隙率越大,则其成核稳定性越好。

Aiming at the problems of undercooling and phase separation of sodium acetate trihydrate(SAT),the optimization experiment of nucleation and thickening for SAT modification is carried out in this article.Experimental results show that disodium hydrogen phosphate is a good nucleating agent,adding 2.0%of it to SAT can effectively solve the problem of undercooling and control the degree of undercooling within 2℃.Also find that xanthan gum(XG)is good thickening agent,adding 1%to 1.5%of it to SAT can effectively inhibit the phase separation.In addition,the scanning electron microscope(SEM)is used to characterize the selected nucleating agent,and it is found that the nucleation stability of the nucleating agent is related to the surface shape.The more rough the surface of the nucleating agent and the greater porosity of the nucleating agent,the better the nucleation stability.