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Self-Healing Spaceship Shielding Could Keep Astronauts Safer
150917自我修复材料让宇航员生命更有保障
撰文： Christopher Intagliata
翻译：马宏
审校：徐丽
It’s a scenario straight out of Hollywood: You’re up in a spacecraft, “you’ve got this capsule around you,” and a loose bolt, a piece of space junk, is zooming your way. “And it’s going really fast. It’s going to very likely pass through your spacecraft and leave both entry and exit holes. So all of a sudden now your atmosphere is rushing out those holes, and you want them sealed right away.”
请想象一个好莱坞式的场景：你驾着心爱的宇宙飞船，在你和茫茫星际空间中间只隔着一层太空舱壁，这时一个之前航天器上掉下来的螺栓出现在你的航道上。这块太空垃圾速度可不慢，要是跟它怼上了，得给你的飞船来个对儿穿。这么一来，舱室里的宝贵气体就会从破洞里喷薄而出，用脚后跟想都知道，得赶紧把洞给补上。
That’s Timothy Scott, a polymer scientist at the University of Michigan, Ann Arbor. He and his team have devised a potential solution to this space disaster: a material that patches itself up, less than a second after impact.
以上的倒霉场景是由Timothy Scott设想的，他是密歇根大学安娜堡分校（University of Michigan, Ann Arbor）的聚合物科学家。这个家伙和他的团队针对这种太空灾难提出了一种可能的解决方案：一种可以在撞击后一秒内自我愈合的材料。
Think of an ice-cream sandwich. “The central part, the ice cream of our sandwich, is a liquid resin.” The cookie parts are sheets of thermoplastic. When a projectile—or piece of space junk—punctures the sandwich, it exposes the liquid part to the ship’s oxygen, which causes it to solidify, patching the hole.
吃过冰激凌三明治么，这个材料结构和它差不多。这种三明治的夹心部分是液态树脂。两侧脆脆的饼干部分是薄层热塑性材料。当来袭物体，比如说一块太空垃圾，击穿三明治的时候，夹层中的液态树脂就会和船里面的氧气接触，接下来树脂就会固化，把洞补上。
The researchers tested sheets of the self-healing material at a firing range, filming the results with high-speed video. And indeed, the material worked fine here on Earth—but they say the findings will have to be replicated under pressure conditions like those you’d find in space. The results are in the journal ACS Macro Letters. [Scott R. Zavada, Nicholas R. McHardy, Keith L. Gordon, and Timothy F. Scott, Rapid, Puncture-Initiated Healing via Oxygen-Mediated Polymerization]
研究人员们在射击场实地测试了这些自我修复材料，顺便还用高速摄像机拍下了实验结果。在地球上这玩意看起来可以完成规定任务，但是他们说得在太空的气压环境下得到同样的结果才成。这些结果被发表在ACS Macro Letters上，感兴趣的话就看看吧。（Scott R. Zavada, Nicholas R. McHardy, Keith L. Gordon, and Timothy F. Scott, Rapid, Puncture-Initiated Healing via Oxygen-Mediated Polymerization）
The space station is already well protected by bumpers that vaporize particles on impact. But protection doesn’t come cheap. “It turns out that robust things are also very heavy. The intent of this is really to provide a backup that’s very low weight.” It costs some $10,000 a pound to launch equipment into space today. So a lighter weight material could save money—and lives.
目前的空间站已经被缓冲材料牢固地保护起来了，这种材料会汽化来袭的微粒。但是这种保护措施也异常地昂贵。研究人员发现要想防护结实坚固，材料就轻不下来。这个新材料设计之初的目的就是提供一种轻巧的替代品。要知道，现在要想把一磅重的设备发射到宇宙中，差不多得花上个10000美元。所以说，更轻的材料不仅可以省钱，也能救命。
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材料科学考研(材料科学考研国家线)