多孔聚丙烯酸钠高吸水性树脂的合成及表面改性

采用水溶液聚合法,以丙烯酸为单体,以过硫酸钾–亚硫酸氢钠为氧化还原引发剂,羧甲基纤维素钠为增稠剂、泊洛沙姆为表面活性剂,无水乙醇和碳酸氢氨为致孔剂,采用物理和化学的方法制得多孔聚丙烯酸钠高吸水性树脂;将制得的多孔高吸水性树脂烘干、粉碎、筛分,取筛分后孔径为150~300μm的多孔高吸水性树脂用乙二醇二缩水甘油醚、十八水合硫酸铝以及聚乙二醇(400)双丙烯酸酯配制的混合溶液进行表面改性。对其进行傅立叶变换红外光谱,扫描电子显微镜,热重分析。结果表明,增稠剂用量为0.8%,表面活性剂用量为0.1%,无水乙醇用量为10%时,吸去离子水倍率为1290g/g和吸0.9%NaCl溶液倍率为106.2g/g。碳酸氢氨用量为10%时,吸去离子水倍率为1065.2g/g,吸0.9%NaCl溶液倍率为113.6g/g。与碳酸氢铵致孔的高吸水性树脂相比,无水乙醇致孔的高吸水性树脂吸水倍率较高,且孔的结构大小和分布更加均匀,改性可明显提高对无水乙醇致孔高吸水性树脂的吸水速度,热稳定性有所改善,但吸水倍率下降。

Synthesis and Surface Modification of Porous Sodium Polyacrylate Superabsorbent Resin

Porous sodium polyacrylate superabsorbent resin was prepared by aqueous solution polymerization with acrylic acid as monomer,potassium persulfate-sodium bisul te as redox initiator,sodium carboxymethyl cellulose as thickener,Poloxamer as surfactant,absolute ethanol and ammonia bicarbonate as porogen,and the prepared porous super absorbent resin was dried,crushed and sieved,the porous sodium polyacrylate superabsorbent resin with pore size of 150 300 μm was surface modi ed by a mixture of ethylene glycol diglycidyl ether,aluminium sulfate octadecahydrate and polyethylene glycol (400) diacrylate. FTIR,SEM and TG analysis were carried out. The results show that the dosage of thickener and surfactant are 0.8% and 0.1%,respectively. When the dosage of absolute ethanol is 10%,the absorbed amount of deionized water is 1 290 g/g and 0.9% sodium chloride solution is 106.2 g/g. When the dosage of ammonia bicarbonate is 10%,the deionized water absorption is 1 065.2 g/g for deionized water and 113.6 g/g for 0.9% sodium chloride solution. Absolute ethanol-porous sodium polyacrylate superabsorbent resin has higher absorption capacity, more uniform pore size and distribution than ammonium bicarbonate. Modi cation can signi cantly increase the water absorption rate of absolute ethanol-porous superabsorbent resin,and improve the thermal stability,but the water absorption rate decreases.