改性聚天冬氨酸/聚丙烯酸复合吸水性树脂的制备与敏感性研究

Synthesis and Responsive Properties of Modified Poly (Aspartic acid)/Poly (Acrylic acid) Composite Absorbent Resin

摘要:

摘要：以丙烯酸（AA）为单体，过硫酸钾（KPS）为引发剂，改性聚天冬氨酸（MKPAsp）作为交联剂，通过水溶液聚合法制得新型聚天冬氨酸/聚丙烯酸(MKPAsp/PAA)复合吸水性树脂。通过红外光谱(FT-IR)、热失重分析(TGA) 和扫描电镜(SEM)对复合吸水性树脂进行了表征。SEM表明PAA的加入，改善了孔道结构，使孔密度增加，孔径更加均匀规则。研究了具有不同组成复合吸水性树脂在不同温度、pH和盐溶液中的溶胀性能，结果表明MKPAsp/PAA复合吸水性树脂的LCST比KPAsp提高了10℃，表现出良好的温度敏感性；在pH为6和10的溶液中出现两个吸液峰值；复合吸水树脂的耐盐性得到了提高，且在不同价态的氯盐中吸液倍率的顺序为Na ＞Fe3 ＞Ca2 。制得的MKPAsp/PAA复合吸水树脂在去离子水和90mmol/L的NaCl溶液中的最佳吸液倍率达到886.7g/g和165.1g/g，分别比KPAsp树脂提高了的3.8倍和2.3倍。

Abstract:

Abstract: A novel modified poly (aspartic acid)/poly (acrylic acid) composite absorbent resin was prepared with Acrylic acid (AA) as the monomer, potassium persulfate (KPS) as the initiator and modified poly (aspartic acid) (MKPAsp) as the crosslinking agent in an aqueous system. The absorbent resin was characterized by infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and thermal gravimetric analysis (TGA). SEM confirmed that the introduction of PAA into the network structure can optimize the pore channel structure, increase the pore density and make the pore sizes become uniform. The swelling properties of the composite resin in different temperature, pH and salt solutions were investigated in this study, the results showed that the LCST of MKPAsp/PAA composite absorbent resin was10℃ high than that of KPAsp, which suggested that MKPAsp/PAA composite absorbent resin had a better temperature sensitivity. The composite absorbent resin had the best swelling ratios at pH=6 and 10; the salt tolerance of the composite resin was significantly enhanced and the absorbency order in different chloride salt solutions was: Na > Fe3 > Ca2 . The optimum swelling ratios of the prepared MKPAsp/PAA composite absorbent resin in distilledwater and 90 mmol/L NaCl solution were 886.7g/g and 165.1g/g respectively, which were enhanced by 3.9 and 2.3 times than that of KPAsp resin.