高粱秸秆-g-聚丙烯基化合物/坡缕石黏土高吸水树脂的制备

以天然高粱秸秆(SS,颗粒直径>180目)作为纤维素源,N,N'-亚甲基双丙烯酰胺(MBA)为交联剂,过硫酸钾(KSB)为引发剂,复配坡缕石(PGS)黏土,通过与丙烯酰胺(AM)及部分中和的丙烯酸(AA)接枝共聚制备低成本高吸水树脂SS-g-P(AA/AM)/PGS。运用扫描电镜(SEM)和红外光谱(FTIR)对高吸水树脂的形貌及结构进行了表征,并测试了其吸水性能及热稳定性。结果表明,在坡缕石黏土和高粱秸秆的添加量占反应体系总质量的19.51%时,SS-g-P(AA/AM)/PGS对蒸馏水、自来水、黄河水的最大吸收量分别为273.0、66.7、60.4 g/g,且热稳定性较好。通过研究树脂的吸水溶胀过程确定了材料的吸水动力学行为,结果表明,SS-g-P(AA/AM)/PGS吸自来水和蒸馏水的过程分别符合Fickon扩散模型和non-Fickon扩散模型。

Preparation of SS-g-P(AA/AM)/PGS Superabsorbent Resin

A low cost superabsorbent resin,SS-g-P(AA/AM)/PGS,based on the natural sorghum straw(SS,particle size>180 mesh) as the source of cellulose,was prepared by grafting copolymerization of acrylamide(AM) and partly-neutralized acrylic acid(AA) on the chain of SS mixed with palygorskite(PGS).The copolymerization was carried out using N,N′-methylene double acrylamide(MBA) as crosslinking agent and potassium persulfate(KSB) as initiator.The morphology and structure were characterized by means of scanning electron microscopy(SEM) and fourier transform infrared spectroscopy(FTIR).The water-absorption capability as well as the thermal stability of the polymers was also characterized.The results show that the superabsorbent resin bears the maximum absorption amount of 273.0 g/g for distilled water,66.7 g/g for tap water and 60.4 g/g for the Yellow River water when the total adding amount of palygorskite and sorghum straw accounts for 19.51% in SS-g-P(AA/AM)/PGS.The dynamic behavior of the resin was also well investigated through the observation of swelling features;it was found that a Fickon and a non-Fickon diffusion model were in accordance with the absorption of distilled water and that of tap water,respectively.