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ABSTRACT: The constant deterioration of the soil as a result of natural and anthropogenic processes produces decrease of soil fertility and agricultural production, increase in the cost of food, desertification, and loss of water resources. The objective of this work was to develop a hybrid composite that structural and functionally mimics the humified structure of soils for the development of remediation strategies based on geotransformation of degraded soils. For that, two different strategies for the modification of clay surface were evaluated: (i) covalent linking using trichlorovinylsilane and (ii) electrostatic interaction using N‐vinylbenzyl‐N‐triethyl ammonium chloride. Later, modified clay was characterized and used as crosslinking agent during the free‐radical polymerization of acrylic acid. Particulate nanostructured polymers were characterized and their water absorption capacity, cationic exchange capacity, and ionic retention capacity were determined. Results showed that clay‐poly(acrylic acid) composites can be obtained by described methodology. In addition, materials with 60 and 80% w/w of modified MMT were obtained with particulate shape, high water absorption capacity (273%–568%), high cationic exchange capacity (124–666 meq+/100 g) and high ionic retention capacity (108–194 and 263–313 meq/100 g for major and minor elements, respectively). Finally, it was concluded that synthesized materials mimic structural and functionally the humified structure of soils. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46211. [ABSTRACT FROM AUTHOR]

ABSTRACT Stimuli-sensitive polymers are a type of smart polymers having the capability to change their configuration or properties under adequate stimuli as heat, pH, magnetic field, mechanical strength, among other. The aim of this work was to synthesize nanostructured polymers with antibacterial properties capable to change their retention properties of divalent metal ions by external stimuli (pH and ionic strength). For that, a polymerizable nanostructured crosslinker (PNC) based on silver nanoparticles (AgNPs) and acrylic acid was synthesized. Later, NPSS was synthesized by free-radical polymerization, characterized by different analytical techniques and its retention properties of divalent ions (Cu2+, Fe2+, Mn2+, and Zn2+) were studied at different pHs and ionic strengths (5.0, 7.0, and 9.0; and 0.0, 0.5, and 1.5% NaCl, respectively). It was evidenced that AgNPs can be synthesized using acrylic acid as stabilizing agent, and later, be used for synthesis of NPSS by free-radical polymerization. For NPSS, metal ion retention decreases as pH is increased; in addition, results suggest that the electrostatic interaction is not the only determining factor in the retention of ions. Other possible factors which would be affecting the retention are: water flow by swelling capacity and water flow by osmotic stress resulting of high salt concentration. NPSS showed antimicrobial activity against Escherichia coli and Staphylococcus aureus which was enhanced by incorporation of PNC based on AgNPs. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46001. [ABSTRACT FROM AUTHOR]