A group at the University of Tokyo has developed a self-reinforcing gel that "strengthens when pulled".
The mainstream of conventional high-strength gels is one in which a fragile bond called "sacrificial bond" is introduced inside, and by selectively breaking the sacrificial bond during deformation, the gel as a whole avoids destruction and improves toughness. I'm letting you.However, since it takes time for the broken bond to recover, it has been a problem in applications where large deformation is repeatedly applied.
On the other hand, the world's first development of this research is a polymer gel that uses a self-reinforcing effect that does not involve the destruction of bonds.By using a "ringing gel" (a polymer gel in which polymer chains are linked by cyclic molecules), which exhibits excellent toughness, and by appropriately adjusting the structure so that the polymer chains are uniformly deformed, Its feature is that it causes "elongation-induced crystallization" when it is elongated.Elongation-induced crystallization is known as a toughening mechanism for natural rubber, and is a phenomenon in which stretched polymer chains gather together and crystallize to become hard, and suppresses gel breakage even when a load is applied. be able to.The elongation-induced crystals disappear instantly when the force is removed and return to their original state, so the self-reinforcing gel has the world's highest level of toughness (more than 10 times that of conventional ringing gels) and almost 100% resilience. It is said that it also has.
This research result shows for the first time in the world that elongation-induced crystallization, which has been known for a long time, is effective not only for rubber but also for gel materials containing a large amount of solvent.Since the polymer gel containing water as the main component has high biocompatibility and can be applied to biomaterials to be embedded in the human body, the self-reinforcing gel developed this time is constant even if a large load is repeatedly applied. It is expected to lead to application to artificial locomotor organs such as artificial ligaments and joints that are required to show a mechanical response.
Paper information:[Science] Tough Hydrogels with Rapid Self-reinforcement
