Layered nanoparticles with surface charge are explored
as rheological
modifiers for extrudable materials, utilizing their ability to induce
electrostatic repulsion and create a house-of-cards structure. These
nanoparticles provide mechanical support to the polymer matrix, resulting
in increased viscosity and storage modulus. Moreover, their advantageous
aspect ratio allows for shear-induced orientation and decreased viscosity
during flow. In this work, we present a synthesis and liquid-based
exfoliation procedure of phenylphosphonate–phosphate particles
with enhanced ability to be intercalated by hydrophilic polymers.
These layered nanoparticles are then tested as rheological modifiers
of sodium alginate. The effective rheological modification is proved
as the viscosity increases from 101up to 103Pa·s in steady state. Also, shear-thinning behavior is observed.
The resulting nanocomposite hydrogels show potential as an extrudable
bioink for 3D printing in tissue engineering and other biomedical
applications, with good shape fidelity, nontoxicity, and satisfactory
cell viability confirmed through encapsulation and printing of mouse
fibroblasts.