改性聚天冬氨酸/聚丙烯酸/羧甲基纤维素复合高吸水性树脂的制备及其性能

Synthesis and Properties of Modified Poly(aspartic acid)/Poly(acrylic acid)/Carboxymethyl Cellulose Composite Superabsorbent Resins

以聚琥珀酰亚胺(KPSI)、丙烯酸(AA)和羧甲基纤维素(CMC)为原料,采用水溶液聚合法合成改性聚天冬氨酸/聚丙烯酸/羧甲基纤维素复合高吸水性树脂(KPAsp/PAA/CMC)。通过红外光谱(FTIR)、热重分析(TGA)和扫描电镜(SEM)对产物的结构、热稳定性和表面形态进行表征。探讨了CMC和AA用量对复合吸水性树脂吸液性能的影响,结果表明,当m(CMC)∶m(AA)∶m(KPSI)=0.15∶3∶1时,树脂的吸液性能最佳,在去离子水和质量分数0.9%的NaCl水溶液(生理盐水)中的吸液倍率分别达到843 g/g和130 g/g。研究了不同组成KPAsp/PAA/CMC吸水性树脂的盐敏感性、温度敏感性和pH敏感性,以及树脂在人工血、人工尿和不同体积分数乙醇水溶液的吸液性能,结果表明,复合树脂盐敏感性提高,在盐溶液中的吸液大小顺序为NaCl>FeCl_3>CaCl_2;低临界溶解温度(LCST)比KPAsp提高了15℃;在溶液pH=5和pH=9出现了两吸液高峰;在人工血和人工尿中的最大吸液倍率为211 g/g和142 g/g,在体积分数为50%的乙醇水溶液中的最大吸液倍率为295 g/g。

Modified poly（aspartic acid）/poly（acrylic acid）/carboxymethyl cellulose composite superabsorbent resins were prepared using modified poly（aspartic acid）（KPAsp）,acrylic acid（AA）and carboxymethyl cellulose（CMC） as raw materials by aqueous solution polymerization. The structure,thermal stability and surface morphology of the products were characterized by Fourier transform infrared（FTIR） spectroscopy,thermal gravimetric analysis（TGA） and scanning electron microscopy（SEM）. The effects of the amount of CMC and AA on the absorption properties of composite absorbent resin were investigated. The results showed that when the mass ratio of AA,CMC and modified polysuccinimide（KPSI） was 0. 15 ∶ 3 ∶ 1,the composite resin exhibited the best swelling capacity. The swelling ratios of the prepared composite resin were 843 g/g in distilled water and 130g/g in physiological saline,respectively. The salt sensitivity,temperature sensitivity and pH sensitivity of the composite resins with different proportions of poly（aspartic acid）,poly（acrylic acid） and carboxymethyl cellulose were studied. Moreover,the absorption properties of resin in artificial blood,artificial urine and ethanol aqueous solution with different volume fraction were discussed. It was foundthat the salt sensitivity of the composite resin was enhanced,and the absorption capabilities of resin in different salt solutions were in the order of NaCl,FeCl_3 and CaCl_2. The lower critical solution temperature（LCST） of the composite resin was higher than that of KPAsp with an increase of 15 ℃.The composite resin displayed the best swelling ratios at pH5 and pH9. The maximum swelling ratios of the composite resin were 211 g/g in artificial blood,142 g/g artificial urine,and 295 g/g in ethanol aqueous solution（50%）,respectively.