High strength nanocomposite hydrogels with outstanding UV‐shielding property

Abstract

A novel series of nanocomposite hydrogels (TAD gels) with high mechanical strength and excellent UVshielding property were prepared by in situ free-radical copolymerization of acrylamide (AM) and N,N-dimethylacrylamide (DMAA) in aqueous solutions of TiO 2 nanoparticles (TiO 2 NPs). It was found that the TiO 2 NPs were uniformly dispersed in the copolymer matrix and acted as inorganic crosslinking agents in TAD gels owing to their hydrogen bonding interactions with polymer chains. The TAD gels exhibited excellent mechanical properties such as large elongations at break, high elastic moduli, and ultimate stresses, all of these properties as well as swelling ratios of TAD gels could be easily controlled by changing the AM ratios and TiO 2 contents in the initial solutions. In addition, the TAD gels with low AM ratios could be prepared into thin films in a customized Teflon model and these films showed high transparency in visible light but could completely block the UV light with wavelength below 366 nm and prevent the methylene blue from degradation under UV irradiation. POLYM. COMPOS., 37:810-817,

High-Strength Nanocomposite Hydrogels with Swelling-Resistant and Anti-Dehydration Properties

“…In addition, the tensile strength of NC-G40 gel, NC-G60 gel, and NC-G80 gel after being placed in air for 10 days were measured to be 0.64 ± 0.04 MPa, 0.53 ± 0.03 MPa, and 0.29 ± 0.01 MPa, respectively. These values are almost the same as those recorded in their as-prepared states and comparable to other high-strength hydrogels reported in the literature [33,34,35]. In general, the data displayed in Figure 8 strongly verified that the NC-G gels could be utilized in air and water environments because of their excellent mechanical performance under these conditions.…”

Highly tough and rapid self-healing dual-physical crosslinking poly(DMAA-co-AM) hydrogel

“…Thus, these results prove the rapid self-healing properties of the present poly(AM-co-DMAA)-based nanocomposite hydrogel, different from a similar poly(AM-co-DMAA)-based nanocomposite hydrogel without self-healing properties albeit with good mechanical strength. 80,81 Notably, our dual-physical crosslinking poly(DMAA-co-AM) hydrogels incorporating a small amount of clay exhibit both excellent elongation at break and self-healing properties. The properties of similar poly(AM-co-DMAA)-based nanocomposite hydrogel are listed in Table 1.…”

Tough and Self-Healable Nanocomposite Hydrogels for Repeatable Water Treatment

“…In this paper, we present a tough and self-healable nanocomposite hydrogel that can be activated by ultraviolet (UV) light to efficiently adsorb heavy metal ions and degrade dye molecules in wastewater. This nanocomposite hydrogel is composed of polymer-network-bridged TiO 2 nanoparticles [32,33]. These TiO 2 nanoparticles have three functions (Figure 1a): (1) as crosslinkers to bridge polymer chains into three-dimensional networks, which in turn constrain the relative positions of these nanoparticles within the matrix [32,33], (2) as binding agents to adsorb water pollutants such as heavy metal ions and dye molecules, and (3) as photocatalysts to generate free radicals under the UV exposure.…”

“…This nanocomposite hydrogel is composed of polymer-network-bridged TiO 2 nanoparticles [32,33]. These TiO 2 nanoparticles have three functions (Figure 1a): (1) as crosslinkers to bridge polymer chains into three-dimensional networks, which in turn constrain the relative positions of these nanoparticles within the matrix [32,33], (2) as binding agents to adsorb water pollutants such as heavy metal ions and dye molecules, and (3) as photocatalysts to generate free radicals under the UV exposure. Unlike the usual organic crosslinkers that only attach several polymer chains, the TiO 2 nanoparticle crosslinkers can attach a large number of polymer chains with inhomogeneous chain lengths.…”