Mechanics and tribology of a zwitterionic polymer blend: Impact of molecular weight.

Despite decades of biomimetic materials development, the tribological properties of articular cartilage remain unrivalled. This manuscript presents the design and material properties of a polymer blend composed of poly (vinyl alcohol) (PVA) and a zwitterionic polysulfobetaine (PMEDSAH) prepared into hydrogel form using a cyclic freeze-thaw method. The PVA hydrogel matrix provides mechanical strength while the zwitterionic polymer, PMEDSAH, is intended to act as a boundary lubricant.

Synthesis and Characterization of Zwitterionic Polymer Brush Functionalized Hydrogels with Ionic Responsive Coefficient of Friction.

Freeze-thaw poly(vinyl alcohol) hydrogels (PVA-H) offer great potential for several biomedical applications due to their biomimetic mechanical properties and biocompatibility. Despite these advantages, the use of PVA-H for load bearing applications has been limited due to poor performance in boundary lubrication compared to natural tissue such as articular cartilage. Recently, zwitterionic polymer brushes have been shown to act as effective boundary lubricants on rigid substrates; however, to the best of our knowledge, the synergistic effects of zwitterionic brushes coupled with the biomimetic fluid load support exhibited by hydrogels have not been reported.

The use of a hydrogel implant in the repair of osteochondral defects of the knee: A biomechanical evaluation of restoration of native contact pressures in cadaver knees.

Background: Osteochondral injuries have been treated by a variety of methods, each having its own drawbacks. The purpose of this study was to determine the biomechanical feasibility of using a hydrogel implant replacement for an osteochondral core defect. The hypothesis of this study was that the contact pressure of the native knee can be recreated with the use of a hydrogel implant.

Synthesis and characterization of a zwitterionic hydrogel blend with low coefficient of friction.

Unlabelled: Hydrogels display a great deal of potential for a wide variety of biomedical applications. Often times the performance of these biomimetic materials is limited due to inferior friction and wear properties. This manuscript presents a method inspired by the tribological phenomena observed in nature for enhancing the lubricious properties of poly(vinyl alcohol) (PVA) hydrogels.

Low friction hydrogel for articular cartilage repair: evaluation of mechanical and tribological properties in comparison with natural cartilage tissue.

The mechanical and tribological properties of a novel biomaterial, a boundary lubricant functionalized hydrogel, were investigated and compared to natural cartilage tissue. This low friction hydrogel material was developed for use as a synthetic replacement for focal defects in articular cartilage. The hydrogel was made by functionalizing the biocompatible polymer polyvinyl alcohol with a carboxylic acid derivative boundary lubricant molecule.

Experimental and numerical tribological studies of a boundary lubricant functionalized poro-viscoelastic PVA hydrogel in normal contact and sliding.

Hydrogels are a cross-linked network of polymers swollen with liquid and have the potential to be used as a synthetic replacement for local defects in load bearing tissues such as articular cartilage. Hydrogels display viscoelastic time dependent behavior, therefore experimental analysis of stresses at the surface and within the gel is difficult to perform. A three-dimensional model of a hydrogel was developed in the commercial finite element software ABAQUS™, implementing a poro-viscoelastic constitutive model along with a contact-dependent flow state and friction conditions.

A novel polyvinyl alcohol hydrogel functionalized with organic boundary lubricant for use as low-friction cartilage substitute: synthesis, physical/chemical, mechanical, and friction characterization.

A novel material design was developed by functionalizing polyvinyl alcohol hydrogel with an organic low-friction boundary lubricant (molar ratios of 0.2, 0.5, and 1.