Here, it was quantified by describing the linear region of the double-logarithmic angular frequency -complex viscosity profiles with a power law (𝜂 * = 𝐾 • 𝜔 '() ) and determining the shear-thinning exponent n (Figure , S9), wherein n = 1 applies to Newtonian fluids and 0 < n < 1 describes shear-thinning fluids. 22 °C GelMA inks and 37 °C GelMA/TbPE inks both displayed strong shearthinning properties with n < 0.3, ascribable to their physically crosslinked microstructures. At the same time, the jammed microstructure of the disjointed PEC micelles in the 37 °C GelMA/DbPE inks resulted in milder shear-thinning behavior, with n ≈ 0.5. In both DbPE and TbPE containing inks, sufficient shear-thinning was observed to enable printing while preserving cell viability. Representative ink formulations were further characterized in terms of their (B) yielding behavior, (C) shearthinning behavior, and (D) structural recovery post-shearing. In (B), constant stress was applied on the inks until a steady state viscosity was observed. In (D), the application of a high shear rate of 𝛾̇ = 100 s -1 for 250 s was followed by a low shear rate of 𝛾̇ = 0.01 s -1 for 500 s. GelMA inks are depicted in black stars, whereas GelMA/TbPE and GelMA/DbPE inks are shown in red squares and blue circles, respectively.