Deposition of hydrogel particle impacting on smooth glass and porous nanofiber mat

Hydrogels are one of the most evolving areas in biopolymers engineering; with different composition, size, and morphology depending on the application field. However, a few is known on the dynamics of hydrogel particles impacting on a solid surface. In this research, an in-air microfluidics system was developed to generate hydrogel particles with an initial diameter of 343–478 μm based on sodium alginate solution using calcium chloride as crosslinker and ethyl alcohol. The impact of hydrogel particles within the “beads-on-thread” flow structure on a homogeneous smooth glass and a heterogeneous porous nanofiber mat (scaffold) was studied to characterize deposition. For successive particle-surface and particle-particle collisions, empirical expressions were derived to determine the deposition parameters of a spreading/deformable hydrogel particle at Reynolds and Deborah numbers of 0.0003–0.002 and 0.19–0.22, respectively. Based on the expressions, the 3D printing technology concept was reported to demonstrate how to produce a honeycomb hydrogel 1-layered material with a set volumetric geometry. In addition, the parameters for the linear motion of a printing node with micronozzles were estimated. The study is motivated by the practical possibility of using multicomponent heterogeneous liquids with a complex internal structure in biomedical technologies to increase their functionality during deposition on a surface. [Display omitted] •Deposition of hydrogel particles – “liquid core-rigid shell” inks – is studied.•Dual flow system with a piezo actuator is developed to generate hydrogel particles.•Empirical expressions are derived for receding diameter and height of a deposited particle.•Particle–surface and particle–particle collisions on smooth and nanofiber surfaces occur.•Honeycomb hydrogel 1-layered material with a set volumetric geometry is modeled.