OAK RIDGE, Tenn. (WATE) – It’s not your average sticky tape. One of the “toughest materials ever reported” in the form of a reusable adhesive has been developed by researchers at the Department of Energy’s Oak Ridge National Laboratory. The new adhesive was made from common household plastics.
ORNL scientists say the technology adapts to bear heavy loads, tolerate extreme stress and heat, and reversibly bond to various surfaces including glass, aluminum and steel.
So, what’s in it and how did they do it? ORNL says its researchers aimed at upcycling a commodity thermoplastic, polystyrene-b-poly(ethylene-co-butylene)-b-polystyrene, or SEBS, a rubbery polymer material that is easy to process, but not engineered for tough adhesion. So they upcycled it and crosslinked it to make it better with more stable properties.
“The goal of upcycling is to add value to common plastics produced in high volume for general and often disposable applications, such as food containers, toys and household items,” ORNL said.
The team modified SEBS’ chemical structure “with dynamic crosslinking to make it more robust, as well as to create reuse pathways for plastics, beyond traditional recycling, that enhance their performance for new and specialized applications.”
Crosslinking can create a bridge between structures that are not normally compatible. In the study, boronic esters were used to couple SEBS with silica nanoparticles, or SiNP, a filler material used to strengthen polymers. The combination yields a novel crosslinked boronic ester-SiNP composite material.
Results showed crosslinked bonds shift within the material to enable specific properties and adhere to surfaces so strongly that a thin square centimeter can hold roughly 300 pounds, according to ORNL.
Testing the technology’s toughness included trying to detach materials with force – and results were off the charts, widely exceeding all commercial adhesives tested in the study.
“The material was so tough in adhering to glass, in fact, that glass fractured before the sample debonded,” ORNL reported. “The approach also enhanced thermal stability to 400 degrees Fahrenheit, making the adhesive attractive for ambient and high-temperature applications.”
The development widens applications for aerospace, automotive and construction adhesives, according to ORNL scientists. “There are benefits to industry and the environment to save resources and reduce waste. By design, this adhesive allows you to make repairs or correct costly mistakes and can be reprocessed for new uses in very challenging applications,” lead author Md Anisur Rahman, who works with in ORNL’s Chemical Sciences Division, said.
The team plans to commercialize the technology and is exploring dynamic crosslinking with other fillers to develop tough adhesives optimized for specific bonding surfaces and functionalities, ORNL said.