用无乳化剂乳液聚合法制备聚丙烯醛微球

本文应用无乳化剂乳液聚合法合成了粒度均一、具有活泼醛基的聚丙烯醛微球,并对丙烯醛聚合动力学和影响微球直径,活泼醛基含量的因素进行了研究。用合成的微球同不同的氨基酸和午血清白蛋白反应,结果表明:该微球在生理pH条件下同含有伯氨基的化合物具有较高的结合容量。因此,在无乳化剂存在下,采用乳液聚合法制备聚丙烯醛微球是一种合成具有干净表面的聚丙烯醛微球的新方法。

PREPARATION OF POLYACROLEIN MICROSPHERES BY MEANS OF EMULSIFIER-FREE EMULSION POLYMERIZATION

Monodisperse polyacrolein (PA) microspheres were prepared by means of emulsifier-free emulsion polymerization of acrolein in aqueous medium using sodium hydroxide as catalyst. The diameter of PA microspheres prepared was in the range from 1.45 to 2.21um, the capacity of reactive aldehyde groups was in the range from 2.591 to 5.199 mmol per gram PA microspheres. The optimum polymerization condition was: acrolein, 7-10%(w/v); pH, 8.5-11.2; temp., 16℃; time, 3.5hr. The diameter of PA microspheres changes with concentration of catalyst and acrolien. The capacity of reactive aldehyde groups of PA microspheres changes with the reaction conditions, e.g., the capacity of reactive aldehyde groups of PA microspheres increases with the decrease of the catalyst concentration when pH>10. The results of PA microspheres reacting with amino acids and bovine serum albumin at physiological pH ran-ge showed that the PA microspheres have a higher binding capacity.