Fabrication of xanthan gum based polymeric hydrogels: Rheological investigation, toughness, and adhesion optimization

Abstract

Integrating excellent adhesiveness and toughness in a single hydrogel remains a challenge due to the poor mechanical properties often seen in adhesive hydrogels. This study investigates the effect of different concentration of tannic acid on the mechanical strength, and adhesive performance of xanthan gum based polymeric hydrogels. The synthesis and surface morphology of the fabricated hydrogels were determined by using FT-IR and SEM analysis respectively. The results showed that the connections between polymer chains play a vital role in enhancing the mechanical properties and adhesive performance of hydrogels. Different rheological tests (frequency sweep, creep recovery, amplitude sweep, and adhesion test) were carried out at various temperatures to study the effect of different amounts of tannic acid, and temperature on the mechanical strength, and adhesive performance of synthesized hydrogels. The rheological models (Bingham, modified Bingham, Ostwald power law, Herschel-Bulkley, and Cross) were applied to check the non-Newtonian pseudo plastic shear thinning behavior of hydrogels, and better percentage recovery (93 % creep recovery) was observed for hydrogels having high (0.009g) tannic acid concentration. The results obtained showed an increase in mechanical, adhesive strength by increasing tannic acid concentration in the hydrogels, and the adhesion strength for fabricated hydrogels as 37.21 kPa, 24.94 kPa, 16.36 kPa, 6.42 kPa shows that adhesion follows the decreasing order as 0.009 > 0.006 > 0.003 > 0g. The higher adhesive nature of p(AA-XG_TA0.009) makes it a good candidate for cloth, rubber, ceramics, and glass repairing.