The propensity for covalent organic frameworks to template polymer entanglement. (https://pubmed.ncbi.nlm.nih.gov/38513024/)

These scientists wanted to see how adding a special type of tiny crystals called covalent organic framework (COF) crystals to different types of plastics would change how the plastics behave. They found that when they mixed these COF crystals with a plastic called polymethyl methacrylate, the crystals stayed on the surface of the plastic. But when they mixed the crystals with another type of plastic called polyimide, the crystals and the plastic formed a strong bond. This bond was created because the plastic chains were able to weave through the tiny holes in the crystals, making the plastic and crystals stick together really well.

This special bond between the plastic and the crystals made the plastic much stronger and tougher. It also helped the plastic to stretch more before breaking. By adding just a small amount of these COF crystals to the plastic, about 1% of the total weight, the scientists were able to make the plastic much better at absorbing energy when it gets hit or bent. This is because the plastic chains could move around and rearrange themselves when under stress, making the plastic harder to break. The scientists found that the key to making this happen was how well the plastic chains could interact with the COF crystals.

Neumann SE., Kwon J., Gropp C., Ma L., Giovine R., Ma T., Hanikel N., Wang K., Chen T., Jagani S., Ritchie RO., Xu T., Yaghi OM. The propensity for covalent organic frameworks to template polymer entanglement. Science. 2024 Mar 22;383(6689):1337-1343. doi: 10.1126/science.adf2573. Epub 2024 Mar 21.