The search is on, then, for biodegradable alternatives. One possibility has recently been explored by David Schiraldi of Case Western Reserve University, in Ohio, and his colleagues. They propose to reach back into history and revive the use of a feedstock that was used to make some of the first plastics invented: milk.
此后,寻找生物可降解替代品的研究一直在持续。最近,俄亥俄州凯斯西储大学的David Schiraldi及其同事已开辟了一条潜在途径。他们追溯历史并改良了塑料在发明之初时所使用的原料---牛奶的使用方法。
What they actually suggest is using casein, the principal protein found in milk. The curds are mostly made of this protein. In 1889 a French chemist called Jean-Jacques Trillat discovered that if casein is treated with formaldehyde the result is a hard, shinysubstance that does well as a substitute for materials like ivory and tortoiseshell. Sowidespread was the enthusiasm for the new material that Queen Mary herself ordered several pieces of jewellery made from it. However, casein-based plastic of this sort is too brittle for general use. It was eventually superseded by the modern, petrochemical variety, andmanufacture stopped altogether by the 1970s.
事实上,他们的建议就是使用牛奶中的主要蛋白质---酪蛋白,凝乳中的大部分成分都是由酪蛋白组成。1889年,法国化学家Jean-Jacques Trillat发现被甲醛处理过的酪蛋白会生成一种坚硬而有光泽的物质,并可以作为铁及龟甲类材料的替代品。之后,这种新材料受到了广泛的热衷以至于玛丽女王自己都定制了一些用这种材料制作的珠宝。但是,这类酪蛋白塑料由于过于脆弱而无法成为一种通用材料。其最终被现代石油化工衍生物所超越,并在20世纪70年代全面停产。
【英语六级外刊阅读 “塑料 旧法新用”选自《经济学人》】相关文章:
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