海藻酸钠/累托石插层复合高吸水性树脂制备及性能

Synthesis and characterization of sodium alginate/rectorite superabsorbent intercalation composite

以海藻酸钠(SA)与钠化累托石(Na+REC)为原料通过水溶液法制备插层纳米复合材料(SA/Na+REC),再以此作为第二组分加入到部分中和的丙烯酸中进行接枝共聚制备SA/Na+REC-g-PAA复合高吸水性树脂。研究了SA/Na+REC复合材料用量、引发剂用量、交联剂用量、中和度等影响高吸水性树脂吸水性能的主要因素。结果表明,产品吸水率达到657g/g,吸盐水率达到118g/g,与同工艺条件的SA-g-PAA高吸水性树脂相比,吸水率提高136g/g、吸盐水率提高14g/g、凝胶模量提高0.5×10-5Pa、干树脂在功率为320W紫外灯照射30d的失重率减少4.2%、水凝胶在70℃,8h后保水率提高4.6%,且吸水速率快,避免了在吸水过程中产生面团现象。XRD表明Na+REC在接枝共聚物基体中部分被剥离,形成插层型复合高吸水性树脂,SEM显示SA/Na+REC-g-PAA复合高吸水性树脂具有多孔的层状结构。

Sodium alginate/Na-rectorite composite was synthesized by water solution processing. Then SA/Na^＋ REC-g-PAA superabsorbent composite was synthesized by graft copolymerization using SA/Na^＋REC and partially neutralized acrylicacid. The influence of amounts of SA/Na^＋REC, initiator, crosslinking agent, neutralization degree of acrylic acid and reaction temperature to the absorbency of the superabsorbent composite was discussed. The results showed that the distilled water absorbency of SA/Na^＋REC-g-PAA is 657g/g, and the saline water absorbency is 118g/g. Compared to SA-g-PAA with same process conditions, the water absorbency of SA/Na^＋REC-g-PAA increased by136g/g, the saline water absorbency increased by 14g/g, the gel modulus increased by 0.5 × 10^-5Pa, the mass loss ratio of dry resin by untraviolated radiation for 30 days, the radiated power was 320W, decreased by 4.2%, the retantion ability decreased by 4.6% after 8h heating at 70℃ and it absorbed water more quckly without dough phenomenon. XRD indicated that partial Na-rectorite were striped and the interaction was formed in SA/Na^＋ REC-g-PAA. SEM showed that SA/Na^＋ REC-g-PAA had microporous and laminate structure.