Dye pollution has become a serious threat to environment and human health. Although versatile hydrogels have attracted intensive attentions due to their outstanding adsorption properties, the ultrahigh adsorption capacity and mechanical property are still two critical challenges for the practical applications. Herein, a super-adsorbent poly(acrylic acid)/laponite (PAAc/Lap) nanocomposite hydrogel with ultrahigh mechanical property and adsorption capacity of methylene blue (MB) is prepared by incorporating physical cross-linking with sparse chemical cross-linking. The hydrogel possesses porous 3D network structures and a fairly high water penetration with 1360 times of swelling ratio, which can allow the internal adsorption sites to be fully exposed and facilitate the adsorption. The adsorption capacity of MB can reach up to 3846 mg/g, which is almost the first time that a PAAc-based adsorbent could display superior adsorption capacity of more than 3800 mg/g towards MB. Important factors affecting the adsorption are also investigated, and the adsorption behavior is well fitted by the pseudo-second-order model and Langmuir isotherm model. More importantly, the appropriate physical cross-linking and sparse chemical cross-linking in the polymeric network endows hydrogel with superior mechanical properties. The tensile stress and strain are as high as 1.18 MPa and 2192%, which can facilitate the expansive applications and practical treatment. Mechanism analyses illustrate that the electrostatic interactions and cation-exchange between the functional groups of hydrogel and MB molecules contribute to the extraordinary adsorption ability. The proposed PAAc/Lap hydrogel with ultrahigh adsorption capacity and mechanical property is highly promising as an efficient super adsorbent for water treatment.

染料污染已成为对环境和人类健康的严重威胁。尽管多功能水凝胶因其出色的吸附性能而受到广泛关注，但超高的吸附容量和机械性能仍然是实际应用的两个关键挑战。在此，通过结合物理交联和稀疏化学交联，制备了具有超高机械性能和亚甲基蓝（MB）吸附能力的超吸附聚（丙烯酸）/合成锂皂石（PAAc/Lap）纳米复合水凝胶。该水凝胶具有多孔的3D网络结构和1360倍溶胀比的相当高的透水性，可以使内部吸附位点充分暴露并促进吸附。MB的吸附容量可达3846 mg/g，这几乎是第一次基于 PAAc 的吸附剂对 MB 表现出超过 3800 mg/g 的优异吸附能力。还研究了影响吸附的重要因素，吸附行为被准二级模型和朗缪尔等温线模型很好地拟合。更重要的是，聚合物网络中适当的物理交联和稀疏的化学交联赋予水凝胶优越的机械性能。拉伸应力和应变高达1.18 MPa和2192%，有利于扩大应用和实际处理。机理分析表明，水凝胶和 MB 分子的官能团之间的静电相互作用和阳离子交换有助于非凡的吸附能力。