Synthetic dry elastomers are polymeric materials that feature cross-linked networks that form into random and unordered shapes and textures. These materials have a host of properties that are applicable in biomedicine, but the randomness of their internal structures at different scales makes it difficult to actually use these elastomers. Now, researchers at Chalmers University of Technology in Sweden have developed a porous elastomer whose properties, including its structure down to the nanoscale, can be fine tuned to produce capabilities such as controlled drug release, replacements for lost tissues, and guiding the growth of healthy new tissues. The researchers have already used the new flexible material to 3D print a nose structure that feels similar to a real nose, as well as various medical devices with surfaces that are inhospitable to pathogens. This application is particularly interesting, as the material’s internal structure is what prevents bacteria from settling into it, so no drugs are needed to keep frequently fouled surfaces clean. The new material can be injected, antimicrobial peptides attached to it, and it can be printed and manipulated in a variety of ways. “There are many diseases where the cartilage breaks down and friction results between bones, causing great pain for the affected person. This material could potentially act as a replacement in those cases,” said Martin Andersson, one of the Chalmers researchers involved in developing the new material that is being commercialized by a company called Amferia. From the study abstract in ACS Nano: Inspired from biological design principles, we report a tough ordered mesoporous elastomer formed via bottom-up lyotropic self-assembly of noncytotoxic, polymerizable amphiphilic triblock copolymers and hydrophobic polymers. The elastomer is cross-linked using covalent cross-links and physical hydrophobic entanglements that are organized in a periodic manner at the nanoscale. This transforms into a well-ordered hexagonal arrangement of nanofibrils that are highly oriented at the micron scale, further organized as 3D macroscale objects. The ordered nano-microstructure and molecular multinetwork endows the elastomer with hierarchical toughening while possessing excellent stiffness and elongation comparable to engineering elastomers like silicone and vulcanized rubber. Study in journal ACS Nano: Tough Ordered Mesoporous Elastomeric Biomaterials Formed at Ambient Conditions Source
