Design and Development of CuCoFe ₂ O ₄ ‐Integrated Gum Acacia‐Grafted‐Poly(N,N‐Dimethylacrylamide) Hydrogels: Structural Insights, Thermal Stability, and Comprehensive Rheological Evaluation

ABSTRACT Hydrogels hold significant promise in biomedical and industrial fields; however, their practical utility is often limited by inadequate mechanical strength, elasticity, and thermal stability. In this study, a high‐performance nanocomposite hydrogel was developed by grafting gum acacia (GA) with poly(N,N‐dimethylacrylamide) [GA‐g‐P(DMA)/GA‐g‐PDMAAm] through free‐radical polymerization using ammonium persulfate (APS) as the initiator and N,N'‐methylenebisacrylamide as the cross‐linker. To further enhance structural and functional properties, CuCoFe ₂ O ₄ (CCF) nanoparticles were incorporated into the polymer matrix, yielding a multifunctional GA‐g‐P(DMA)/CCF nanocomposite hydrogel. Comprehensive FTIR and XRD analyses confirmed successful grafting, uniform nanoparticle dispersion (≈50–70 nm), and increased cross‐linking density. Thermogravimetric studies revealed markedly improved thermal stability, with the decomposition onset shifting from ~250°C for pristine GA‐g‐P(DMA) to ~310°C for the nanocomposite. The char yield also nearly doubled (~22% vs. ~11% at 600°C), indicating enhanced thermal resistance and structural integrity. Rheological measurements showed dominant solid‐like viscoelastic behavior, with the storage modulus ( G ′) consistently higher than the loss modulus ( G ″). Incorporation of 50 mg CCF nanoparticles resulted in a threefold increase in G ′ (from ~1.2 × 10 ³ Pa to ~3.6 × 10 ³ Pa at 1% strain). The complex viscosity ( η *) exhibited pronounced shear‐thinning and thermoresponsive characteristics, decreasing from ~820 Pa·s at 25°C to ~260 Pa·s at 70°C. Herschel–Bulkley modeling further confirmed pseudoplastic, non‐Newtonian flow behavior, underscoring suitability for injectable and 3D‐printable applications. Thus, the synergistic reinforcement provided by CCF nanoparticles significantly enhances the mechanical, thermal, and rheological performance of GA‐based hydrogels, establishing the GA‐g‐P(DMA)/CCF nanocomposite as a promising candidate for biomedical scaffolds, controlled drug delivery, and wastewater treatment systems.