遇水崩解型聚苯乙烯崩解机理及性能

采用原位共混聚合的方法将反相乳液聚合得到的交联聚丙烯酸钠吸水树脂微粒混入聚苯乙烯材料中,得到聚苯乙烯/聚丙烯酸钠共混物(PS/PAANa),共混物遇水后会崩解成含水凝胶的聚苯乙烯粉末,并失去机械强度。用扫描电镜观察材料水崩解前后的微观结构,并研究了材料的崩解机理。测试了材料的力学强度和水崩解产物的吸水性能。结果表明:此材料的崩解机理为在分散剂Span-80的作用下,吸水树脂吸水后膨胀导致基体聚苯乙烯出现银纹并扩展为裂缝,裂缝继续扩展,最终导致基体崩解为粒径0.05～0.2mm的粉末;PS与PAANa原位共混后,力学强度提高;共混物的崩解产物吸水倍率可达26倍。

Disintegrable Mechanism and Property of Water-disintegrable Polystyrene

In-situ polymerization was adopted to prepare PS/PAANa blends by blending PS and the crosslinked PAANa water absorption resin particle which was prepared via inverse emulsion polymerization.The blend is disintegrated into PS powder containing hydrogel in water and loses its mechanical strength.The microstructure of PS/PAANa blends were observed by SEM before and after disintegration,the disintegrable mechanism was explored,the mechanical property of the blends and the water absorption property of the disintegrated product were tested as well.The results show that:after adding dispersant Span-80,the resin absorbs water and expands,then the craze appears in the matrix PS and turns into cracks,at last,the matrix is disintegrated into powder(diameter 0.05～0.2mm);the mechanical strength of the blend is enhanced after in-situ polymerization;the water absorption rate of disintegrated product of the blend is up to 26.