Hydrogels were produced from mixtures of polyvinyl alcohol (PVA), polyvinyl pyrrolidone (PVP), and acrylic acid (AAc) using γ-radiation at doses of 3, 7, and 10 kGy and the effect of the variation in concentration of AAc within 0%–3% (w/v) on the gelation, swelling, crosslinking, thermal properties, crystallinity, mechanical properties, and surface morphology of the hydrogels were characterized and their adsorptive removal properties for methylene blue (MB) was investigated. The swelling trend was pH-dependent which was dictated by the dominance of two competing factors namely, crosslink density and hydrophilicity. Although thermal analysis showed that the presence of AAc decreased the thermal stability of the hydrogels, SEM images exhibited gradual morphological changes establishing the role of AAc as a crosslinker, and thus increasing the elastic moduli, toughness, and crystallinity of the hydrogels. However, correlation between the characterization results revealed that, in spite of AAc occupying some of the crosslinking sites within PVA–PVP networks, at low concentration (1% w/v), it could not polymerize enough to contribute to the crosslinks. FTIR spectral analysis revealed a possible gelation mechanism along with the points of interaction among the gel-components. MB adsorption capacity of the hydrogels reached a maximum of 117 mg/g following pseudo-second-order kinetics through film diffusion mechanism while the adsorption isotherm resembled most with that of Langmuir.

水凝胶由聚乙烯醇 (PVA)、聚乙烯吡咯烷酮 (PVP) 和丙烯酸 (AAc) 的混合物制成，使用剂量为 3、7 和 10 kGy 的 γ 辐射以及 AAc 浓度变化的影响在 0 %–3% (w/v) 对水凝胶的凝胶化、溶胀、交联、热性能、结晶度、机械性能和表面形态进行表征，并研究了它们对亚甲基蓝 (MB) 的吸附去除性能。溶胀趋势取决于 pH 值，这取决于两个竞争因素的主导地位，即交联密度和亲水性。尽管热分析表明 AAc 的存在降低了水凝胶的热稳定性，但 SEM 图像显示出逐渐的形态变化，确立了 AAc 作为交联剂的作用，从而增加水凝胶的弹性模量、韧性和结晶度。然而，表征结果之间的相关性表明，尽管 AAc 占据了 PVA-PVP 网络中的一些交联位点，但在低浓度 (1% w/v) 下，它无法聚合到足以促进交联。FTIR 光谱分析揭示了一种可能的凝胶机制以及凝胶组分之间的相互作用点。通过薄膜扩散机制遵循准二级动力学，水凝胶的 MB 吸附容量达到最大值 117 mg/g，而吸附等温线与 Langmuir 的吸附等温线最相似。尽管 AAc 占据了 PVA-PVP 网络中的一些交联位点，但在低浓度 (1% w/v) 下，它无法聚合到足以促成交联的程度。FTIR 光谱分析揭示了一种可能的凝胶机制以及凝胶组分之间的相互作用点。通过薄膜扩散机制遵循准二级动力学，水凝胶的 MB 吸附容量达到最大值 117 mg/g，而吸附等温线与 Langmuir 的吸附等温线最相似。尽管 AAc 占据了 PVA-PVP 网络中的一些交联位点，但在低浓度 (1% w/v) 下，它无法聚合到足以促成交联的程度。FTIR 光谱分析揭示了一种可能的凝胶机制以及凝胶组分之间的相互作用点。通过薄膜扩散机制遵循准二级动力学，水凝胶的 MB 吸附容量达到最大值 117 mg/g，而吸附等温线与 Langmuir 的吸附等温线最相似。