Plastic is everywhere in our modern world. Its toughness makes it an extremely useful material from household items to vehicle parts, but that same toughness makes it hard to break down for recycling or disposal (处理). However, Japanese scientists at the University of Tokyo have developed a new plastic material that can be broken down more easily and can self-heal and remember past shapes.
Based on a kind of plastic called an epoxy resin vitrimer, which is brittle (脆性的), the new plastic has a huge range of advantages. Once scratched (刮划) with a knife, it can completely patch itself up after being heated to 150 ℃ for just 60 seconds. When shaped into the shape of a crane, then flattened, it can fold itself back into the crane shape by being heated up. It does all of this much faster than others of its type.
The new plastic can also break down easier. Even if it’s thrown into the environment, it still has less of a problem than other kinds of plastic, which the team demonstrated by placing it in seawater for 30 days. It biodegraded (生物降解) by 25% and released something that is eatable for ocean life.
The new plastic is more resistant to breaking. It can also repair itself, and can recover its original memorized shape. It even biodegrades safely in a ocean environment, according to Shota Ando, a researcher of the study.
The material can be used in a variety of applications. “Building materials for roads and bridges are often composed of epoxy resins mixed with compounds (化合物) such as concrete and carbon,” said Ando. “By using the new plastic, these would be easier to maintain as they would be stronger and healable using heat. Unlike conventional epoxy resins, this new material is hard but flexible, so it could also be expected to strongly bond materials of different hardness and stretch.”
【小题1】What is the author’s purpose in writing paragraph 1?| A．To introduce the topic of the text. | B．To show the disadvantages of plastic. |
| C．To highlight the importance of plastic. | D．To show his views on previous plastic. |
| A．Change itself. | B．Destroy itself. | C．Repair itself. | D．Burn itself. |
| A．It is safe for animals in the ocean. | B．It is made up of concrete and carbon. |
| C．It can change its shape when frozen. | D．It is more brittle than previous plastic. |
| A．How to Make a New Plastic | B．An Interesting Scientific Study |
| C．The Widespread Application of Plastic | D．A New Environmentally Friendly Plastic |
