A novel assessment of microstructural and mechanical behaviour of bilayer silica-reinforced nanocomposite hydrogels as a candidate for artificial cartilage.

A novel assessment of microstructural and mechanical behaviour of bilayer silica-reinforced nanocomposite hydrogels as a candidate for artificial cartilage. J Mech Behav Biomed Mater. 2021 Jan 18;116:104333 Authors: Mostakhdemin M, Nand A, Ramezani M Abstract The complex structure of healthy articular cartilage facilitates the joint withstanding the imposed pressures and retaining interstitial fluid to lessen stresses on its soft tissue, while easing the locomotion and minimising friction between cartilage mates. Avascular nature of this tissue results in unrecoverable damaged lesions and severe pain over time. Polymeric hydrogels are promising candidate materials for the replacement of the damaged cartilage. Hence, a tough bilayer nanocomposite acrylamide-acrylic acid hydrogel reinforced with silica nanoparticles (SNPs) was designed and synthesised. The mechanical characterisations showed a significant increase in compressive strength up to 1.4 MPa and doubled elastic modulus (240 kPa) by utilising only 0.6 wt% SNPs compared to the non-reinforced hydrogel. The optimum amounts of monomers and SNPs resulted in the compression of samples up to 85% strain without failure. Viscoelastic responses improved as the stress relaxation lessened to half in all nanocomposite hydrogels. Diffusion rate theory was applied, and the results showed to what extent elastic modulus results in an improvement in stress relaxation. The proposed hydrogel f...
Source: Journal of the Mechanical Behavior of Biomedical Materials - Category: Materials Science Authors: Tags: J Mech Behav Biomed Mater Source Type: research