Plant Cell Wall’s ‘Glue’ May Be the Key to Wooden Skyscrapers
Wooden Skyscrapers have always been the dream, but the question was ‘Can they hold?’ Now, the answer might be closer than ever, with the Durpees new discovery of a “Glue” that sticks the plant cell wall together. Father and son, Ray Dupree and Paul Dupree from the Universities of Warwick and Cambridge, solve the prevailing mystery of how main polymers in plant cells bind together forming a strong indigestible wall. Paul Dupree says: “We knew the answer must be elegant and simple. And in fact, it was.” So here is the matter in short.
HAUT, a proposed 240-foot timber-framed tower to be built in Amsterdam. Image Courtesy of Team V Architectuur
Xylan and Cellulose are the Earth’s most common polymers. They are found in the walls of materials like wood and straw, determining their strength and digestibility. To form these walls, Xylan and Cellulose have to stick together, but their seemingly incompatible nature made it seem unlikely. Xylan is long and twisting, with sugars and molecules attached to it, whereas Cellulose is thick and rod-like. Paul Durpee from the Department of Biochemistry at Cambridge and the leader of the research resolves the mystery: “What we found was that cellulose induces xylan to untwist itself and straighten out, allowing it to attach itself to the cellulose molecule. It then acts as a kind of ‘glue’ that can protect cellulose or bind the molecules together, making very strong structures.” Professor Ray Dupree, from the University of Warwick and a co-researcher added: “By studying these molecules, which are over 10,000 times narrower than the width of a human hair, we could see for the first time how cellulose and xylan slot together and why this makes for such strong cell walls.” This revelation was the result of an unanticipated discovery, by Professor Paul Durpee and his colleagues in Cambridge, which shows that Xylan has attached sugars and molecules, known as decorations, only on one side of it.
According to Paul Dupree, various industries might be dramatically influenced by the discovery. He explains that the digestion of the tough plant walls can be made easier by fully understanding the nature of what binds them together. He furtherly explains by giving paper production as an example: “Enormous amounts of energy are required for this process. A better understanding of the relationship between cellulose and xylan could help us vastly reduce the amount of energy required for such processes.”
So, how is all of this related to architecture, and more specifically to Wooden skyscrapers?
Durpee clarifies that the discovery’s value does not lie only with the breaking down of materials. He says it can, also, be useful for the manufacturing of stronger materials like strengthened composite wood. Then, he refers to the plans for sustainable wooden houses in the UK, in which he is involved as a member of the Centre for Natural Material Innovation at the University of Cambridge.
The enhanced wood may open the door to a bright future for sustainability, when applied on a much larger scale like on skyscrapers. The possibility is currently being researched.
