P(BA-MMA-AAK)对AN相稳定和吸湿性的影响研究

Influences of P(BA-MMA-AAK) on the Phase Stabilization and Moisture Absorption of Ammonium Nitrate

用合成的丙烯酸丁酯-甲基丙烯酸甲酯-丙烯酸钾三元共聚物[P(BA-MMA-AAK)]改性硝酸铵(AN),研究其对AN相稳定和吸湿性的影响。结果表明:当P(BA-MMA-AAK)的添加量为3%(质量分数)时,可以防止AN在53℃附近的相转变,并将AN 84℃左右的转晶温度提高到100℃左右;75%相对湿度时,改性后AN的24 h平均吸湿率降低10.6%。研究表明,P(BA-MMA-AAK)对AN的改性主要是由于以下两方面的影响:一方面是钾盐的影响;另一方面是P(BA-MMA-AAK)中的疏水性链段在AN表面形成疏水区的影响。

The ammonium nitrate （ AN ） was modified by using home-made butyl acrylate-methyl methacrylate-potassium acrylate [P（BA-MMA-AAK）], and the influences of P（BA-MMA-AAK） on the phase stabilization and mois-ture absorption of obtained AN were tested by DSC and XRD. Results show that when the mass fration of P （ BA-MMA-AAK） is up to 3%, theⅣ→Ⅲphase transition of AN at 53℃ is effectively eliminated, while theⅢ？Ⅱphase-transition temperature increases from 84 ℃ to 100 ℃. Furthermore, the 24 h average moisture absorption rate of AN （75% R. H. ） reduces by 10. 6%. Consequently, P （ BA-MMA-AAK） can be used as phase stabilizer of AN mainly because of the existence of potassium and the hydrophobic segments of P（ BA-MMA-AAK） which form a hydrophobic region on the surface of the ammonium nitrate.