Ultra-high strength hydrogel bio-lubricant prepared by Lanzhou Institute of Chemistry

Hydrogel is a type of polymer material with a large amount of moisture and has a three-dimensional network structure. It has important application prospects in the areas of joint lubrication, tissue engineering, and drug controlled-release carriers, and has received extensive attention. Hydrogels also have very similar properties to many active tissues in the human body, such as the lubricated cartilage and muscle tissue of human joints, making hydrogels an ideal alternative to artificial joints and the best base material for developing muscle drivers. . However, hydrogels are generally fragile and subject to mechanical stress after being subjected to external forces, thus greatly limiting their application.

In order to solve the problem of poor mechanical properties of hydrogel materials, researcher Zhou Feng of the Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, used molecular engineering design to prepare an ultra-high strength hydrogel with a double cross-linked network (Molecularly Engineered Dual- Crosslinked Hydrogel with Ultrahigh Mechanical Strength, Toughness, and Good Self-Recovery), which has a novel structure in which the covalent bond and the coordination bond are double-crosslinked, in which the chemical cross-linking forms an inert hydrogel cross-linked The network, followed by the use of ferric ion-carboxylate coordination bonds as a dynamic cross-linking form, can dynamically break the coordination bonds to dissipate energy after being subjected to external stress, thereby greatly improving the hydrogel's mechanical properties.

The hydrogel exhibits super high tensile strength at break, fracture stress greater than 6 MPa, elongation at break greater than 700%, and excellent mechanical properties. Moreover, since the broken coordination bond during stretching is a reversible non-covalent bond, the broken coordination bond after stretching can be re-formed in a short time, thus restoring the original state of the hydrogel. Shows excellent fatigue resistance. The material is expected to gain important applications in areas such as joint lubricants and artificial blood vessels.

This research work was recently published in Advanced Materials, 2015, 27(12), 2054-2059.