Assembly of Polyacrylamide-Sodium Alginate-Based Organic-Inorganic Hydrogel with Mechanical and Adsorption Properties

Abstract

Hydrogels have been widely used in water purification. However, there is not much discussion and comparison about the effects of different nanofillers on the reinforcement and adsorption performances of hydrogels, which can be subjected to rapid water flow and possess strong adsorption ability. In this work, polyacrylamide (PAAM)-sodium alginate (SA) interpenetrating polymer network-structured hydrogels were prepared by in situ polymerization. PAAM formed the first flexible network and SA constructed the second rigid network. Three kinds of inorganic nanoparticles including carbon nanotubes (CNTs), nanoclays (NCs), and nanosilicas (NSs) were incorporated into a PAAM-SA matrix via hydrogen bond. The obtained hydrogels exhibited a macroporous structure with low density (≈1.4 g/cm3) and high water content (≈83%). Compared with neat PAAM-SA, the hydrogels with inorganic nanoparticles possessed excellent mechanical strengths and elasticities, and the compression strength of PAAM-SA-NS reached up to 1.3 MPa at ε = 60% by adding only 0.036 g NS in a 30 g polymer matrix. However, CNT was the best filler to improve the adsorption capacity owing to its multi-walled hollow nanostructure, and the adsorption capacity of PAAM-SA-CNT was 1.28 times higher than that of PAAM-SA. The prepared hydrogels can be potential candidates for use as absorbents to treat wastewater.

Electrospun Functional Materials toward Food Packaging Applications: A Review

“…In order to achieve multi-function for nanofiber-based food packaging materials, various fillers have been added into polymer substance, especially inorganic fillers that possess conductivity, magnetism, antibacterial property, etc. [98][99][100][101]. Then, a nanofiber-based food packaging material could be prepared through the electrospinning technique.…”

Current Advances of Polymer Composites for Water Treatment and Desalination

“…e adsorption capacity of the fabricated polymer-CNT composite was 1.28 times higher than that of polymer composite only. Figure 7 simply summarizes the synthetic route of this polymer-CNT composite, its morphological structure, and its adsorptive characteristics [37]. Also in another study, polyaniline grafted multiwalled-CNT composite was prepared by an oxidation polymerization process.…”

“…Schematic illustration of synthesis of singled-walled CNTs incorporated copolymer membrane of poly(N-isopropylacrylamide)co-(acrylamide) and their use in oil removal from water-oil mixture (reproduced with a permission from[33]). (a) Schematic illustration of composite formation, (b) SEM image of the freeze-dried polymer network hydrogel, (c) a magnified area of CNT distributed in the polymer matrix, and (d) polyacrylamide-sodium alginate-CNT composite (reproduced with a permission from[37]). …”

Simulation of Percolation Threshold, Tunneling Distance, and Conductivity for Carbon Nanotube (CNT)-Reinforced Nanocomposites Assuming Effective CNT Concentration

“…Polymer carbon nanotubes (CNTs) nanocomposites (PCNT) are very attractive from research and application points of view, because they can elucidate important properties when the concentration of nanoparticles reaches the percolation threshold, which is the minimum CNT content that produces the conductive networks in nanocomposites [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15]. Long and thin CNTs normally introduce a low percolation threshold, producing a conductive nanocomposite by incorporation of very low CNT content [16].…”