For us and the environment, there is a significant amount of plastic reduction research for many and different applications. For the first time, researchers have found a way to give relatively durable paper materials some of the beneficial properties of plastic. This can be done easily, cost-effectively and efficiently. A coating called Choetsu not only ensures the waterproofness of the paper, but also preserves its flexibility and also safely degrades.
It is difficult to avoid the fact that plastic materials are by and large harmful to the environment. You’ve probably seen images of plastic pollution washing away on the beach, damaging rivers and killing countless animals. However, the problem often seems completely out of our hands, given the ubiquity of plastic materials in everyday life. Professor Dandy Hiroi of the Institute of Solid State Physics at the University of Tokyo and his team are exploring ways in which materials science can help, and their recent discovery aims to replace some uses of plastic with something more sustainable: paper.
“The main problem with plastic materials, as I see it, is their inability to degrade quickly and safely,” Hiroi said. “There are materials that can safely degrade, such as paper, but obviously paper cannot meet the wide range of uses of plastics. However, we have found a way to give the paper some good properties of plastic but without harm. We call it Choetsu, an inexpensive biodegradable coating. which adds waterproofing and strength to plain paper ”.
Choetsu is a combination of materials that, when applied to paper, spontaneously create a strong and waterproof film in contact with moisture in the air. The coating consists of safe and inexpensive chemicals, mainly methyltrimethoxysilane, a small amount of isopropyl alcohol and a small amount of tetraisopropyltitanate. Paper structures, such as food containers, are sprayed or immersed in this liquid mixture and dried at room temperature. After drying on cellulose consisting of paper, a thin layer of silica is formed, containing methyl, a type of alcohol, providing durable and waterproof properties.
In addition, the reactions that occur during coating automatically create a layer of titanium dioxide nanoparticles. They create the property to repel dirt and bacteria, known as photocatalytic activity, which protects the coated object over a long period of time. All the chemicals involved in the coating break down over time into harmless substances such as carbon, water and silicon sand.
“The technical task has been completed, and some applications may be implemented in the near future, such as items for consumption, packaging or storage of food,” said Hiroi. “Now we hope to use this approach for other types of materials. The liquid composition can be customized for other materials and we can create a dirt and mold resistant coating that can form on glass, ceramics and even other plastics so I hope together with Yoko researcher Iwamiya, who works in this field, and the rest of my team, we will be able to do something truly useful for the world. “
Source of history: