The researchers noticed the seaweed Durvillaea Antarctica, also known as "the strongest kelp in the world" stuck firm while it was being battered by waves at the bottom of a cliff during an Otago Peninsula walk, and set to work researching the chemistry of how it adheres.
They are not the first group to try and understand how underwater superglues work, a discovery which could help the marine and medical industries. Nature seems to have it all figured out, as any boat owner who has tried to clean barnacles or mussels off the bottom of their boat will tell you. Trying to mimic how sea creatures are able to firmly stick to surfaces in wet environments could result in glue that far exceeds any synthetic product that exists today.
Science has shown that mussels cling to rocks and other surfaces using L-Dopa amino acid rich proteins which they secrete through their feet in the form of silky threads. Barnacles secrete a tiny drop of oil on to the surface they want to stick to which repels water, giving them a "dry" region to stick to. Sandcastle worms store their biological glue internally at a low pH until they need it then use the higher pH of seawater to slowly cause the glue to solidify.
This new seaweed research, published in the Journal of the Royal Society, shows how the Kiwi kelp secretes an initial meshwork thread coating which sticks first, then secretes a secondary adhesive which crosslinks and cures the glue over time.
With this combined information, moves towards biomimetic or glues copied from nature can be made, all thanks to a curious tramp along one of New Zealand's scenic walks.
So why doesn't glue stick to the inside of the bottle? Well, glue needs air to set - white glue needs air for water evaporation and superglue requires air moisture to cause a chemical reaction. As glue bottles are designed to minimise the amount of air inside, those reactions don't occur as long as you leave the top on.