02045naa a2200217 a 450000100080000000500110000800800410001902400520006010000160011224501330012826000090026130000140027052013690028465300130165365300200166670000220168670000270170870000180173570000160175377300580176921325012022-06-10       2021    bl uuuu     u00u1 u    #d7 ahttps://doi.org/10.1007/s10924-021-02120-72DOI1 aPFEIFER, M.  aEffect of different surface?charged lamellar materials on swelling properties of nanocomposite hydrogels.h[electronic resource]  c2021  a3311?3323  aThis study investigated the efect of diferent surface-charged lamellar materials on the swelling and difusion properties of synthesized polyacrylamide-methylcellulose hydrogels (HG). Montmorillonite and thermally activated hydrotalcite (300 °C and 550 °C) were incorporated during the preparation of nanocomposite (NC) hydrogels. A series of NC hydrogels were prepared by varying the lamellar material content (1:1, 2:1 and 4:1). The results showed that the HG with hydrotalcite (550 °C) was strongly dependent on the ionic intensity, and that the swelling degree increased by 50%, 65% and 78% with reducing the hydrotalcite content at (1:1), (2:1) and (4:1), respectively. The water absorption capacity of HG containing montmorillonite or hydrotalcite (300 ºC) was slightly afected when the pH was decreased from 7 to 3. However, the pH variation from 7 to 10 increased the water absorption capacity of most HG, except those containing hydrotalcite (550 °C) at (2:1) and (4:1). The presence of lamellar nanoparticles in hydrogels made the polymer matrix more rigid, and less likely to absorb water. In contrast, HG with hydrotalcite (550 °C) at (2:1) and (4:1) showed anomalous behavior with an increase in their water absorption capacity. The results support that the developed NC-HG can be suitable candidate materials for controlled released applications  aHydrogel  aSwelling degree1 aANDRADE, F. A. C.1 aBORTOLLETTO-SANTOS, R.1 aAOUADA, F. A.1 aRIBEIRO, C.  tJournal of Polymers and the Environmentgv. 29, 2021.