Magnetic Fe₃O₄ Nanoparticle/ZIF-8 Composites for Contaminant Removal from Water and Enhanced Flame Retardancy of Flexible Polyurethane Foams

Abstract

In order to separate heavy-metal ions from contaminated wastewater and further realize the reutilization of waste adsorbent, magnetic composites with flowerlike structure were successfully synthesized. After the absorption of Cu 2+ ions, hybrids can be used as effective coatings to enhance the fire safety of flexible polyurethane foam (FPUF) through a dip-coating method. As-fabricated metal−organic framework (MOF)-based composites exhibited a core−shell and flowerlike structure with high thermal stability. The maximum adsorption capacity for Cu 2+ could reach 292.13 mg•g −1 , calculated from the Langmuir isotherm model. In order to reutilize the adsorbed Cu 2+ ions, the CuOloaded MOF-derived Fe 3 O 4 @ZnO@CuO (MO) was obtained with a simple heat treatment. The effectivity of MO as a fire-safety coating for inhibiting the release of heat and toxic gases of FPUF was satisfactory. The application of this MOF-based composite will provide useful insights into the design of bifunctional materials for efficient wastewater remediation and fire-safety coatings.

Sonochemical Approach of Highly Thermal, Mechanical, and Corrosion Inhibition Performance of Metal–Organic Framework (ZIF‐8)‐Decorated Waterborne Polyurethane Nanocomposite

“…In addition, the pure ZIF‐8 has a char residue of ≈30 wt%. [ 46 ] It is expected to have an equivalent amount of residue after the thermal degradation of the composite films. The char residue at 600 °C indirectly reflects the amount of filler on the composite film.…”

Fireproof Nanocomposite Polyurethane Foams: A Review

“…It is noted that the incorporation of basalt wastes and fly ash in the PU matrix led to better thermal stability of the composite foam (hence, higher temperatures of PU thermal decomposition) and higher char yield. Inorganic nanomaterials such as nanoparticles (NPs) are another class of FR additives occasionally used in composite PUFs [ 120 , 187 , 188 , 189 , 190 , 191 , 192 , 193 , 194 ]. For example, silica NPs have been introduced in PUFs via sol-gel deposition [ 187 , 189 ].…”

“…In these works, a dramatic increase in the fire resistance of final composite foams was achieved owing to the synergetic effect of nanoscale carriers and phosphorous-containing FR ( Figure 11 ). Metal oxide NPs were applied in composite PUFs very recently [ 191 , 192 , 193 ]. The MgO and ZnO NPs added in combination with ATH increased the LOI values of the corresponding PUFs by 3% [ 192 ], whereas modification by CuO-loaded Fe 3 O 4 @ZIF-8 nanocomposite (where ZIF-8 is zeolitic imidazolate framework) decreased both magnetic properties and the pHRR value by 69% [ 193 ].…”

Composites Filled with Metal Organic Frameworks and Their Derivatives: Recent Developments in Flame Retardants

“…CCT showed that both THR and TSP are reduced, and the mechanical properties are improved [ 153 ]. In addition, there are studies to introduce more metallic elements or flame-retardant elements, and some other properties will be taken into account while enhancing the flame-retardant properties [ 154 , 155 ]. It is suggested that the use of MOFs as derivatives to combine other hybrids, in connection with many other application scenarios, broadens the limits of single use.…”