This work narrates the synthesis of poly (acrylic acid) hydrogel microparticles (PAAHMPs), fabrication of silver nanoparticles (AgNPs) inside the structure of the prepared PAAHMPs and catalytic applications of PAAHMPs fabricated with AgNPs (PAAHMPs/AgNPs). The PAAHMPs were prepared by inverse suspension polymerization technique while fabrication of AgNPs was carried out by chemical reduction method using sodium borohydride (NaBH₄) as reducing agent. The identification of functional groups in bare PAAHMPs and in the PAAHMPs/AgNPs composite system was carried out by the Fourier transform infrared spectroscopy. The size and morphology of the prepared hydrogel and its composite was studied by scanning electron microscopy and transmission electron microscopy. X‐ray diffraction and thermal gravimetric analyzer was also used to characterize the bare PAAHMPs and PAAHMPs/AgNPs composite. The prepared PAAHMPs/AgNPs composite was used as catalyst for the reduction of nitro aromatic pollutants and an industrial dye, that is, 4‐Nitrophenol (4‐NP), 2‐Nitrophenol (2‐NP) and methyl orange. No loss in catalytic activity was noted in seven consecutive cycles of recycling process while only 37.5% loss in catalytic activity was observed upon storing the catalyst for 90 days.

中文翻译：

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用银纳米颗粒制备的聚（丙烯酸）水凝胶微粒：合成，表征和催化应用

这项工作叙述了聚（丙烯酸）水凝胶微粒（PAAHMPs）的合成，制备的PAAHMP结构内部的银纳米颗粒（AgNPs）的制造以及用AgNPs（PAAHMPs / AgNPs）制备的PAAHMP的催化应用。PAAHMPs采用反相悬浮聚合技术制备，而AgNPs的制备则采用硼氢化钠（NaBH ₄）作为还原剂。通过傅立叶变换红外光谱法对裸露的PAAHMPs和PAAHMPs / AgNPs复合系统中的官能团进行鉴定。通过扫描电子显微镜和透射电子显微镜研究了制备的水凝胶及其复合材料的尺寸和形态。X射线衍射和热重分析仪还用于表征裸露的PAAHMP和PAAHMP / AgNPs复合材料。所制备的PAAHMPs / AgNPs复合物可用作还原硝基芳香族污染物和工业染料的催化剂，即4-硝基苯酚（4-NP），2-硝基苯酚（2-NP）和甲基橙。在回收过程的七个连续循环中未观察到催化活性的损失，而将催化剂储存90天后仅观察到了37.5％的催化活性的损失。