The present study aimed to synthesize poly(2-acrylamido-2-methyl-1-propansulfonic acid-co-acrylic acid), p(AMPS-c-AA), embedded with silver nanoparticles and to investigate their potential in catalysis. The hydrogels were prepared from 2-acrylamido-2-methyl-1-propansulfonic acid (AMPS) and acrylic acid (AA) monomers via free radical polymerization reaction technique in the mild reaction condition and silver nanoparticles were fabricated within hydrogel by reducing Ag (I) ions using NaBH₄ as reducing agent. The synthesized p(AMPS-c-AA) hydrogel was characterized by Fourier transform infrared (FT-IR), scanning electron microscopy (SEM) and nuclear magnetic resonance spectroscopy (NMR). Silver nanoparticles embedded in p(AMPS-c-AA) hydrogel were visualized by transmission electron microscopy (TEM). The metal content of composites was estimated via atomic absorption spectroscopy (AAS). Applications of this synthesized hydrogel was also investigated by using as a catalyst in the reduction of 4-nitrophenol and H₂ generation from hydrolysis of sodium borohydride (NaBH₄). The activation energies, enthalpy, and entropy for 4-NP reduction and NaBH₄ hydrolysis catalyzed by composite were determined. P(AMPS-c-AA)-Ag composite was also used as catalyst in the aerobic oxidation of alcohols by emphasizing the effects of different parameters such as temperature, substituent effect, etc. Finally, recycling of the poly(AMPS-c-AA) hydrogel fabricated with Ag nanoparticles was carried out for four consecutive cycles and no significant loss in catalytic activity was observed.

中文翻译：

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银纳米粒子嵌入的阴离子交联共聚物水凝胶：一种有效的催化剂

本研究旨在合成嵌入银纳米颗粒的聚（2-丙烯酰胺基-2-甲基-1-丙磺酸-共丙烯酸）p（AMPS- c -AA）并研究其催化潜力。在温和的反应条件下，通过自由基聚合反应技术，由2-丙烯酸酰胺基-2-甲基-1-丙磺酸（AMPS）和丙烯酸（AA）单体制备水凝胶，并通过还原Ag（I）在水凝胶中制备银纳米颗粒。 NaBH ₄作为还原剂的离子）。合成的p（AMPS- c -AA）水凝胶的特征在于傅立叶变换红外光谱（FT-IR），扫描电子显微镜（SEM）和核磁共振波谱（NMR）。嵌入p（AMPS-c- AA）水凝胶通过透射电子显微镜（TEM）观察。复合材料的金属含量通过原子吸收光谱法（AAS）估算。还通过使用该合成水凝胶作为催化剂来还原由硼氢化钠（NaBH ₄）水解产生的4-硝基苯酚和H ₂，研究了其应用。确定了复合材料催化的4-NP还原和NaBH ₄水解的活化能，焓和熵。通过强调温度，取代基效应等不同参数的影响，P（AMPS- c -AA）-Ag复合材料还被用作酒精的好氧氧化催化剂。最后，聚（AMPS- c-AA）用Ag纳米颗粒制备的水凝胶连续进行了四个循环，未观察到催化活性的明显损失。