Enhancement of poly(vinyl alcohol) using delaminated layered double hydroxide for the formulation of mechanically strong nanocomposite hydrogel

Abstract

ABSTRACTIn this work, a new type of nanocomposite hydrogel (NCH) has been prepared by crosslinking poly(vinyl alcohol) (PVA) with delaminated layered double hydroxides (LDHs). The LDH was first intercalated with sodium dodecyl sulfate to facilitate delamination. The intercalated LDH was synthesized via coprecipitation followed by subsequent hydrothermal treatment and delamination in dimethyl sulfoxide. The mechanical properties of PVA–NCH with 0.1 wt % LDH were significantly enhanced. The tensile strength of PVA–NCH containing 0.1 wt % LDH was remarkably increased by threefold, while the value of Young's modulus was recorded to be the highest compared to other ratios. The morphologies and microstructures of the PVA–NCH were further investigated by scanning electron microscopy, transmission electron microscopy (TEM), Fourier transform infrared, and X‐ray diffraction. TEM image showed the LDH was delaminated into single nanosheets. It was demonstrated that the delaminated LDH played an important role in increasing physical crosslinking with PVA macromolecules to form strong hydrogel through hydrogen bonding network.RESEARCH HIGHLIGHTS A fast and simple intercalation process of layered double hydroxides (LDHs) with dimethyl sulfoxide to delaminate the organically modified LDH at room temperature. Delaminated Mg2Al–LDH was used as a nanocrosslinker to produce mechanically strong poly(vinyl alcohol) nanocomposite hydrogel. Enhanced mechanical properties in terms of tensile strength and modulus of elasticity (Young's modulus) were observed with the addition of 0.1% sodium dodecyl sulfate–LDH. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48637.