Better, more sustainable adhesives:
Many of our home products and industrial products are held together with very strong adhesives such at epoxies. Ever tried to take some apart? Broke your fingernails? Gave up? So do recycling industries.
Many adhesives are very hard to degrade, and used items end up indefinitely in landfills in millions of tons, while some are releasing toxic chemicals such as formaldehyde. Moreover, some adhesives are made with derivatives of the very concerning compound bisphenol A that affects our sex hormones.
In the September 14th issue of the journal Science, Clayton Westerman and colleagues report creating new super strong adhesives with major benefits. They looked at biological adhesives such as are made by mussels (the shellfish) to attach themselves so well to rocks. The new adhesives can be tuned for strength as needed, some being stronger than the best epoxies. They are made from renewable materials – soy oil, malic acid (the tang of apples), and tannic acid (astringents as in tea). Their bonds can be degraded at the end of the useful life of the items they make by adjusting the chemical composition. At this moment they cost about 50% more than traditional adhesives but we can expect costs to come down… or we can agree to pay for better products!
This has been an outreach activity of the Las Cruces Academy, viewable at GreatSchools.org
Nature 14 Sept. 23, pp. 308-311
