The Deswelling of IPN Hydrogel Tablets by Lattice Boltzmann Method

• Published in: Transport in porous media Vol. 148; no. 3; pp. 559 - 576
• Main Authors: Toro, David J., Boschetti, Pedro J., Vera, Natalia, Pelliccioni, Orlando, Sabino, Marcos A.
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.07.2023; Springer Nature B.V
• Subjects: Acrylamide; Civil Engineering; Classical and Continuum Physics; Diffusion coefficient; Earth and Environmental Science; Earth Sciences; Geotechnical Engineering & Applied Earth Sciences; Hydrogels; Hydrogeology; Hydrology/Water Resources; Industrial Chemistry/Chemical Engineering; Polymers; Polyvinyl alcohol; Simulation; Species diffusion; Tablets; Deswelling of hydrogels; Mass transfer simulation; Lattice Boltzmann method; Deswelling simulation; Mass released from hydrogel
• ISSN: 0169-3913; 1573-1634
• DOI: 10.1007/s11242-023-01960-2

The deswelling of cylindrical copolymeric and interpenetrating-polymer-network (IPN) hydrogel tablets was simulated by employing the lattice Boltzmann (LB) method. Polyvinyl alcohol (PVA) was employed as an interpenetrated phase. The mass concentration of the diffusing species released from the polymer network as a function of time was obtained experimentally at 298.15 and 310.15 K. The computational method utilized to simulate the deswelling of hydrogel samples is based on a two-dimensional multiple-relaxation-time (MRT) LB model with axisymmetric symmetry. The discretization errors of the simulations were calculated using the grid convergence index (GCI) method. The computational method simulated the deswelling behavior with high reliability according to the experimental data, reaching coefficients of determination equal to or greater than 0.98500 for the finest grid in each case. These simulations allowed us to obtain the equilibrium diffusion coefficient and, furthermore, to observe how the normalized swelling concentration profile of two samples with the same formulation at different temperatures changes during the deswelling process, which is not possible experimentally. The PVA as an interpenetrated phase in hydrogel samples of acrylamide slows down the deswelling process and reduces the effect of the temperature on the extrapolated equilibrium diffusion coefficient during deswelling according to the copolymeric samples. Article Highlights The deswelling of hydrogels can be simulated using a computational method based on the lattice Boltzmann method. The deswelling process can be slowed down by adding polyvinyl alcohol as an interpenetrated phase in hydrogel samples of acrylamide. The internal deswelling process can be illustrated by a simulation based on previous experimental data.