高粱秸秆-g-聚丙烯基化合物/坡缕石黏土高吸水树脂制备及动力学研究

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

摘要:

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)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，在坡缕石和高粱秸秆的添加量占反应体系的19.8%时，SS-g-P(AA/AM)/PGS对蒸馏水和自来水的最大吸收量分别为273.0g/g和66.7g/g，且热稳定性较好。通过研究树脂的吸水溶胀过程研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。

Abstract:

A low cost superahsorbent 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 scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The water-absorption capability as well as the thermal stability of the polymers were also characterized. The results show that the superabsorbent resin bears the maximum absorption amount of 273.0 g/g for distilled water and 66.7 g/g for tap water when the total adding amount of palygorskite and sorghum straw accounts for 19.8% in SS-g-P (AA/AM)/PGS. The dynamics behavior of the resin was also well investigated through the observation of swelling features, and was found that a Fickon and a non-Fickon diffusion model were accordance with the absorption of distilled water and tap water, respectively.