400 million tons of plastic are generated annually, most of which comes from single-use plastic While countries are making progress in reducing this waste through paper bags and straws, there are still applications where the properties of plastic are necessary.
Transparent (透明的) wood is an alternative for such applications and is highly preferred since it prevents the harm of petroleum-derived (石油衍生的) plastic products. German scientist Siegfried Fink first created transparent wood in the year 1992, and over the past three decades it has been significantly improved by other researchers as well.
In its natural form, wood is not transparent. However, researchers have found that removing lignin, a naturally occurring biopolymer that provides structural support for the plant tissue, can make it transparent. To do so, the wood is soaked in a warm solution consisting of multiple chemicals, followed by boiling it in another solution. This removes the lignin completely and turns the wood white. However, the space that was occupied by lignin needs to be filled up to maintain structural integrity. This process is done by using a resin (树脂) at a temperature of 185 Fahrenheit (85℃).
The final product can have as much as 90 transparency, and it doesn’t break easily. More importantly, it is more biodegradable than glass or plastic.
While transparent wood isn’t commercial yet, it has been employed in a wide variety of applications ranging from construction to energy storage, making flexible electronics and packaging.
The researchers at the Indian Institute of Technology ( IIT) conducted a life-cycle analysis (LCA) of transparent wood to determine the environmental impact of its production and end-of-life (EOL) cycle. The study found that using hydrogen peroxide for delignification, followed by using epoxy for infiltration, was the most eco-friendly. When scaled up for industrial production, the former method would lower electricity consumption by as much as 98. 8 percent.
EOL analysis showed that transparent wood had a reduced ecological impact compared to polyethylene (聚乙烯), paving the way for it to be commercially adapted to replace the petroleum-based material.
【小题1】Why is transparent wood preferred compared to plastic?| A．It is easier to make. | B．It is environmentally friendly. |
| C．It can be used longer. | D．It can be used repeatedly. |
| A．The natural form of wood. | B．The importance of chemicals. |
| C．How transparent wood is made. | D．How lignin keeps wood strong. |
| A．It can be recycled. |
| B．It will replace plastic soon. |
| C．The most eco-friendly way to produce it. |
| D．Potential damage caused by it to the environment. |
| A．Promising. | B．Difficult. | C．Profitable. | D．Uncertain. |
