Because they can reversibly change their size and shape under different conditions, hydrogels are attractive for a range of applications, including artificial muscles, drug delivery, and sensors. The materials tend to be brittle, however, breaking easily when stretched, and this has prevented their commercialization. Now, researchers at Nagoya University and the University of Tokyo have designed hydrogels with temperature and pH sensitivities that are extremely stretchable as well as mechanically strong, reports Phys.org, based on a study published in Nature Communications.
The new hydrogel structure was inspired by recent research on a "slide-ring gel," in which molecules can slide through the holes in a figure-eight-shaped junction of cross-linked polymers, writes Lisa Zyga on Phys.org. By minimizing stress on the polymer network, the so-called pulley effect strengthens the hydrogel.