Chen Mingyang, Shen Yong, Xu Lihui, Xiang Guanghong, Ni Zhewei
School of Textile and Clothing, Shanghai University of Engineering Science Shanghai 201620 PR China
RSC Adv. 2020 Nov 11;10(67):41022-41031. doi: 10.1039/d0ra07074b. eCollection 2020 Nov 9.
Superabsorbent polymers as soft materials that can absorb water have aroused great interest in the fields of agriculture and forestry. Water absorption and water retention performance of a hydrogel are important indicators to evaluate its practical application. However, few reports show that hydrogels have both excellent water absorption and water retention properties. To date, superabsorbent hydrogels with a swelling capacity of more than 3000 g g have rarely been reported. In this work, a novel superabsorbent poly(acrylic acid) (PAA)-based nanocomposite hydrogel (NC gel) was prepared free radical polymerization of acrylic acid by using vinyl hybrid silica nanospheres (VSNPs) as the cross-linking agent. The PAA NC hydrogel achieved a great swelling ratio of more than 5000 times in deionized water at 323 K, and the swollen hydrogel could hold 60% moisture when it was exposed to the air at 303 K for 42 h. Moreover, the hydrogel also obtained a good swelling ratio of 136 g g in NaCl solution. The PAA NC hydrogel showed excellent repetitive swelling ability. The influences of variable factors (acrylic acid, initiator and sodium hydroxide) on the swelling ratio of the NC hydrogel were researched. It can be speculated that the PAA NC hydrogel has potential application in agriculture and forestry areas due to its excellent water absorption and water retention properties.
高吸水性聚合物作为能够吸收水分的软材料，在农业和林业领域引起了极大的关注。水凝胶的吸水和保水性能是评估其实际应用的重要指标。然而，鲜有报道表明水凝胶同时具有优异的吸水和保水性能。迄今为止，溶胀能力超过3000 g/g的高吸水性水凝胶鲜有报道。在这项工作中，通过使用乙烯基杂化二氧化硅纳米球（VSNPs）作为交联剂，通过丙烯酸的自由基聚合制备了一种新型的基于聚（丙烯酸）（PAA）的高吸水性纳米复合水凝胶（NC凝胶）。PAA NC水凝胶在323 K的去离子水中实现了超过5000倍的高溶胀率，并且当在303 K的空气中暴露42小时时，溶胀的水凝胶可保持60%的水分。此外，该水凝胶在NaCl溶液中也获得了136 g/g的良好溶胀率。PAA NC水凝胶表现出优异的重复溶胀能力。研究了可变因素（丙烯酸、引发剂和氢氧化钠）对NC水凝胶溶胀率的影响。可以推测，PAA NC水凝胶因其优异的吸水和保水性能在农业和林业领域具有潜在应用。
