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WASHINGTON— As if we didn’t have enough of it, the new must-have gadget - the consumer-grade 3-D printer - works with plastic. Researchers in Belgium say they have developed a new environmentally-friendly plastic, suitable not only for 3-D printers, but also for medicinal use.

　　Since the early 1980s, 3-D printers have evolved from highly sophisticated lab instruments into affordable consumer items, enabling their owners to create their own increasingly complex designs.

　　Some futurologists see this as the beginning of the third industrial revolution, but environmentalists fear that the last thing the world needs is more nearly immortal plastic objects in landfills and oceans.

　　The main culprit is non-biodegradable petroleum-based plastic. There are environmentally friendly alternatives like polylactic acid plastic, or PLA, based on sugar from maize and sugarcane -- but they are more expensive.

　　Michiel Dusselier, a researcher at the University of Leuven, said scientists have found a way to manufacture PLA faster and cheaper than before.

　　"Instead of a two-step process currently, it's a one-step process. Our process runs about 100 degrees centigrade lower in temperature and our productivities, which is kind of how much product can you make per volume of reactor per hour, are much higher and our product is also much cleaner, so we don't make side products," said Dusselier.

　　PLA is one of the few types of plastic suitable not only for 3-D printers but for some biodegradable medical items such as suture threads.

　　"I think there will now be much more players in the market giving you the product at much lower prices and I think this will maybe really be the start of the PLA into the bio-plastic business," said Bert Sels, a professor at the University of Leuven.

　　Although PLA is not suitable for all applications, a petrochemical company is already developing the new process for mass production, raising hopes that more plastic products will soon be made of biodegradable chemicals.

　　自20世纪80年代以来，3D打印机从高尖端的实验室仪器成为能负担得起的消费产品，让用户得以进行越来越复杂的设计。

　　一些未来学家视之为第三次工业革命的开始，但环保人士担心这个世界最不需要的是垃圾堆和海洋中的几乎不会消失的塑料品。

　　主要的罪魁祸首是不能生物降解的石油基塑料，目前有环境友好型的替代品，比如基于玉米和蔗糖中糖分制成的聚乳酸塑料(PLA)。

　　Michiel Dusselier是卢汶大学一名研究员，他说科学家发现能比以前更快速、廉价生产PLA的办法。

　　“和目前的两步走生产程序不同的是，这个只需一步。我们的成产工艺所需温度要低100多摄氏度，而且每小时利用反应锅生产的产量要高很多，而且更廉价，所以我们没有副产品。”

　　PLA是少数不仅适合3D打印机，而且适合制造缝合线等可生物降解医疗用品的塑料材料之一。

　　卢汶大学大学教授Bert Sels说，“我想未来市场上将有更多生产者，能提供更低的价格，我想这可能就是PLA进入生物塑料行业的开始。”

　　尽管PLA不适合所有用途，但已经有一家石化公司在研究批量生产的新工艺，这让人们希望不久将有更多塑料产品是生物降解化学品制成。

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