A team of researchers from Penn State unveiled a new self-healing nanocomposite material capable of repairing itself even after it is cut in half. The polymer nanocomposite is strengthened with functionalized boron nitride nanosheets.
Together, the nanocomposite material is capable of recapturing all of its structural and electrical properties – including mechanical strength, breakdown strength to protect against surges, electrical resistivity, thermal conductivity and insulation. The thin strip of material can also hold up to 200 grams of weight after recovering.
Unlike other healable materials, the boron-nitrate nanosheets the Penn State team used are unaffected by moisture, meaning it could also be used in high humidity environments, such as a shower.
“This is the first time that a self-healable material has been created that can restore multiple properties over multiple breaks, and we see this being useful across many applications,” said Professor Qing Wang.
Most self-healable materials are soft or “gum-like,” according to Wang, but the material he and his colleagues created is very tough in comparison. Like graphene, boron/nitride nanosheets are two dimensional, but instead of conducting electricity like graphene, they resist and insulate against it. The material is able to self-heal because boron nitride nanosheets connect to one another with hydrogen bonding groups functionalized onto their surface. When the two pieces are placed near each other, the attraction naturally occurring between the pieces draws them close together. When the hydrogen bond is restored, the two pieces are “healed.”
In the past, researchers have been able to create self-healable materials that can restore one function after breaking, but restoring a suite of functions is critical for creating effective wearable electronics. For example, if a dielectric material retains its electrical resistivity after self-healing but not its thermal conductivity, which could put electronics at risk of overheating.
Watch the video below for a visual of how the nanocomposite heals itself.