We investigate the rheology of synthetic organic fiber–reinforced xanthan gum solutions, via varying fiber concentration (0–4 g/L), length (1.8–12 mm), and temperature (10–50 \(^\circ\) C). Steady shear sweeps, oscillatory amplitude sweeps, and creep tests are performed. Three regimes are identified: (i) weak-interaction, where short fibers or low concentrations have little effect; (ii) shear-responsive networks, where intermediate fibers form weak structures at low shear that collapse under higher shear; and (iii) network-dominated, where higher concentrations and longer fibers increase viscosity across all shear rates and intensify non-Newtonian behavior. Oscillatory and creep tests confirm progressive network formation, increased elasticity, higher storage modulus, and elevated crossover stresses. Creep data show a transition from fluid-like to bounded, solid-like deformation. Temperature induces thinning, partly offset at higher loadings, while longer fibers raise yield stress and consistency, especially at high concentrations.
