Gels and hydrogels

Gels are materials composed of a three-dimensional crosslinked polymer or colloidal network immersed in a fluid. They are usually soft and weak, but can be made hard and tough. Hydrogels are gels that have water as their main constituent.

Latest Research and Reviews

  • Reviews |

    Supramolecular gels comprise low-molecular weight gelators that assemble by non-covalent interactions. In this Review, a range of fabrication methods, as well as strategies for shaping, structuring and patterning supramolecular gels are discussed.

    • Phillip R. A. Chivers
    •  & David K. Smith
  • Research |

    We fabricated the doubly crosslinked gel by stretching the gel during the gelation using tetra-PEG gels. In this gel, two networks having different reference states coexist with and balance each other, influencing Young’s modulus (E) and permanent set (λs). We tuned the time for the stretching imposition on the gels, which influences the 1st network fraction (g1/g0). λs increased with increasing the 1st network fraction, while E had a maximum value against g1/g0, which were explained by the balance between the strain energies of the first and second networks.

    • Takuya Katashima
    • , Ung-il Chung
    •  & Takamasa Sakai
  • Research | | open

    The development of artificial muscle-like actuators is often hampered by the lack of general fabrication routes towards anisotropic responsive materials. Here, the authors fabricate anisotropic hydrogels by an in-situ polymerization strategy of a lamellar network, crosslinked by metal nanostructure assemblies.

    • Haili Qin
    • , Tan Zhang
    • , Na Li
    • , Huai-Ping Cong
    •  & Shu-Hong Yu
  • Research | | open

    Without the introduction of new functional groups, it is often difficult to alter the properties of a substance, such as by changing it from a non-self-healing to a rapidly self-healing material. In this work, we report that the properties of 2-hydroxyethyl methacrylate and acrylamide (HEMA/AAm) hydrogels can be easily altered from non-self-healing to rapidly self-healing materials by simply tuning the reaction temperature. The stretching capabilities of the hydrogels can be greatly enhanced by up to 30-fold. The hydrogels also exhibit good adhesive performance to various substrates. These results provide valuable insight regarding the design of self-healing hydrogels.

    • Rui Chen
    • , Xiubin Xu
    • , Danfeng Yu
    • , Minhuan Liu
    • , Chuanghong Xiao
    • , Ian Wyman
    • , Zhengping Wang
    • , Hui Yang
    •  & Xu Wu
  • Research | | open

    Many bacteria swim with run-and-tumble motion in unconfined fluid. Here the authors report that confinement of these bacteria in a 3D porous medium changes this motion into hopping and trapping, in which the cells are intermittently and transiently trapped as they navigate the pore space.

    • Tapomoy Bhattacharjee
    •  & Sujit S. Datta

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