New Hybrid Polymer Can Move Like Muscles, Recharge and Repair Itself

Some of the most amazing technologies ever invented are ones that mimic things the human body already does, such as pumping like the heart, flexing like joints or dilating like the iris. Now, a totally new type of polymer is repeating that play with the ability to contract and expand like muscles, and potentially repair itself the way some cells in the body are able to regenerate.Picture1

Its ability to mimic certain actions of the human body could mean the hybrid polymer, created by scientists at Northwestern University, could one day do even more amazing things. In announcing their discovery through Northwestern’s news portal, researchers predicted the polymer could one day serve as the foundation for a rechargeable medication delivery patch, artificial muscles and other lifelike materials, or even replaceable energy sources.

The polymer achieves its amazing abilities by combining a polymer with a strong covalent bond with a supramolecular polymer that has weak non-covalent bonds. Integrating the polymers creates a unique structure, one that has a rigid skeleton — courtesy of the covalent polymer — and compartments created by the supramolecular polymer. One of the polymer’s creators, Professor Samuel I. Stupp, director of the university’s Simpson Querrey Institute for BioNanotechnology, says that compartment is key to the versatility of the polymer.

Stupp, who is the senior author of a paper published in Science describing the new polymer, says the “softer” portions of the polymer structure can be animated (to move like muscles) or recharged (to fill and refill with medication). In addition to medical applications, researchers also foresee the polymer being useful in a number of other ways.

“We can create active or responsive materials not known previously by taking advantage of the compartments with weak non-covalent bonds, which should be highly dynamic like living things. Some forms of these polymers now under development in my laboratory behave like artificial muscles,” Stupp says. “I can envision this new material being a super-smart patch for drug delivery, where you load the patch with different medications, and then reload it in the exact same compartments when the medicine is gone.”

Covalent polymers have been broadly used for years. Supramolecular polymers are a more recent discovery, and they offer plastic-like properties with higher molecular weight and all the improved material properties derived from greater molecular weight. The Northwestern scientists have found a way two marry the two types of polymers together to create something truly new and exciting.