PAAM高吸水树脂反相悬浮聚合

采用反相悬浮聚合法,通过部分中和丙烯酸与丙烯酰胺共聚制备了聚(丙烯酸-丙烯酰胺)(PAAM)高吸水树脂,讨论了聚合过程主要影响因素对其吸液性能的影响,并对其进行了FTIR、TGA测试,得到最佳的合成工艺配方:单体质量浓度为30%,中和度N为75%,丙烯酸与丙烯酰胺的摩尔比为7∶3,交联剂、引发剂和分散剂质量浓度分别为0.065%、0.7%和0.5%(相对于单体总质量),单体溶液的滴加速度为2～3mL/min,聚合温度和时间分别为70℃和1.5h。此时在蒸馏水、0.9%NaCl溶液%(wt)中最大吸水倍率分别为Qw=1300g/g、Qs=93g/g(Qw为蒸馏水中吸水倍率,Qs为0.9%NaCl溶液中的吸水倍率,下同),树脂在320℃之前都是比较稳定的,可以适应较高的使用温度。

Inverse Suspension Polymerization of PAAM High Water-absorbing Resin

Sueprabsorbents poly(acrylic acid/acrylamide)(PAAM) are prepared from partly neutralized acrylic acid(AA) and acrylamide(AM) by inverse suspension copolymerization.The influence of some main factors on its absorbency such as mol ration and neutralization of the monomers,the mass concentrations of the crosslinker,the initiator,and the initial temperature and the reaction time is discussed in detail.And then the structure and thermal property of PAAM are tested by FTIR and TGA.The optimum formula is obtained as follow:the mass concentration of all monomers(w) is 30%,the neutralized degree(N) is 75%,mol ratio of acrylic acid(AA) and acrylamide(AM) is 7:3,the mass concentrations of the crosslinker(NMBA),the initiator(KPS) and the dispersing agent relative to all total monomers mass are 0.065%,0.7% and 0.5%,respectively,the drop-additive rate of the monomers solution is 2-3ml/min,the polymerizarion temperature and time are 70℃and 1.5h.The maximum absorbencies of PAAM in distilled water and in 0.9%NaCl solution under the optimum formula are 1300g/g and 93g/g.The thermal stability of PAAM before 320℃ is good.