阿拉伯胶基高吸水树脂的合成与吸水性能

Synthesis and Water Absorbency of Gum Arabic-Based Superabsorbent Resin

以阿拉伯胶(GA)、丙烯酰胺(AM)、α-丙烯酰胺-2-甲基丙磺酸(AMPS)为原料,通过接枝共聚制备了高吸水性树脂GA-g-P(AM/AMPS),利用FTIR、SEM和XRD表征了树脂的结构和形貌,并考察了树脂的溶胀行为。结果显示:GA加入量为10%(以单体AM和AMPS的总质量为基准)时,树脂在去离子水和生理盐水中的最大吸水倍率分别为835和96 g/g。树脂在pH=2和pH=7溶液中表现出良好的响应性和可逆性能,且在pH=4~11的范围内能保持较高的吸水倍率。放置200 min时,树脂在外界温度为100、80和60℃时的保水率分别为43%、65%和76%。在NaCl溶液中,当树脂浓度从2 mmol/L增加到50 mmol/L时,树脂的吸水倍率从321 g/g减少到105 g/g,当树脂浓度为10 mmol/L时,树脂在NaCl、BaCl_2、FeCl_3溶液中的吸水倍率分别为152、66和18g/g。表面活性剂对树脂的吸水性能有显著的影响,表面活性剂浓度从2 mmol/L增加到50 mmol/L时,树脂在十二烷基硫酸钠(SDS)和十六烷基三甲基溴化铵(CTAB)溶液的吸水倍率分别从374、295 g/g降低为101、30 g/g。

Novel graft copolymer（ GA-g-PAM/AMPS） superabsorbent resins based on gum arabic（ GA）,acrylamide（ AM） and α-acrylamido-2-methyl-1-propanesulfonic acid（ AMPS） were synthesized by graft copolymerization. The structure and morphology of superabsorbent resin were characterized by FTIR,SEM and XRD. The swelling behaviors of superabsorbent resin in different solutions were also studied. The results showed that the resin containing 10% GA（ based on total mass of AM and AMPS） showed the highest water absorbency of 835 g/g and 96 g/g in the deionized water and in normal saline,respectively. The resin showed remarkable sensitivity and reversibility in pH = 2and pH = 7 solutions and maintained high water absorbency in the pH range from 4 to 11. The water retention rate of the resin was 43%,65% and 76% at 100 ℃,80 ℃ and 60 ℃,respectively. When the concentration of the resin increased from 2 mmol/L to 50 mmol/L in NaCl solutions,the water absorbency of the resin decreased from 321 g/g to 45 g/g. However,when the concentration of the resin was 10 mmol,the water absorbency in NaCl,Ba Cl2 and Fe Cl3 solutions were 152 g/g,66 g/g and 18 g/g,respectively. In addition,the surfactants could obviously affect the water absorbency of the resin. As the concentration of surfactants increased from 2 mmol to 50 mmol/L,the water absorbency in sodium dodecyl sulfonate（ SDS） solution decreased from 374 g/g to 101 g/g,whereas that in cetyltrimethyl ammonium bromide（ CTAB） solution decreased from 295 g/g to 30 g/g,respectively.