XG-g-PAA/OMMT有机-无机杂化复合高吸水性材料

利用溶液聚合法制备了黄原胶-g-聚丙烯酸/有机蒙脱土(XG-g-PAA/OMMT)有机-无机杂化复合高吸水性材料。当蒙脱土用量为丙烯酸质量的6%时,XG-g-PAA/OMMT的吸水倍率高达882 g/g,吸w(NaCl)=0.9%的水溶液倍率达到106.5 g/g。借助红外光谱仪、X射线衍射仪、扫描电镜、差示扫描量热仪和热重分析仪对合成产物进行了研究。结果表明,黄原胶分子与丙烯酸发生接枝共聚,蒙脱土的加入改变了XG-g-PAA的晶态结构,使复合高吸水性材料形成的网络空间增大,吸水抗盐性能和热稳定性能提高。通过研究复合高吸水性材料的吸水溶胀过程探讨其吸水动力学机理,表明XG-g-PAA/OMMT的吸水动力学扩散模型主要为non-Fickon扩散。

XG-g-PAA/OMMT Organic- Inorganic Hybrid Composite Super Absorbent Material

Xanthan gum-g-acrylic acid/montmorillonite(XG-g-PAA/OMMT) organic-inorganic hybrid composite super absorbent material was prepared by solution polymerization.When the amount of montmorillonite was 6% of the mass of acrylic acid,the water absorbency was up to 882 g/g,and w(NaCl)=0.9% water solution absorbency reached 106.5 g/g.Fourier transform infrared spectroscopy(FTIR),X-ray diffraction(XRD),differential scanning calorimetry(DSC) and thermogravimetric analyzer(TGA) were used to characterize the compound.The results show that the acrylic acid molecule linked to the molecular chain of xanthan gum through graft co-polymerization,and the addition of montmorillonite changed the crystal structure of XG-g-PAA,made the composite super absorbent material form a bigger space network structure,and improved its water absorption,salt resistance and thermal stability.The water absorption kinetics mechanism has been discussed through studying the swelling process of the composite super absorbent material,which shows that its diffusion model is mainly of a non-Fickon one.