当物品损坏了 你就把它们扔掉
When things break, you throw them out.
无论是便宜的塑料储物盒 还是昂贵的光学眼镜
Whether it’s your cheap plastic Tupperware or your pricy prescription glasses, it’s
他们不会自我修复 对吗？
not going to fix itself, right?
但是 如果它们可以呢？
But what if it could?
科学家正在发明一种材料可以自行修复 或者说自疗 所以如果有一天
Scientists are inventing materials that repair themselves, or “self-heal”, so that someday
所以的物品 从轮胎到工具 到人行道 都可以无限期的使用
all kinds of things — from tires to tools to sidewalks — will be able to last indefinitely.
正在开发的这种材料是一种橡胶 能够自行结合 到一起
One kind of material that’s being developed is a kind of rubber that can stitch itself back together.
如果将它切开 把两部分对接在一起 他们最终就会重新 结合在一起
If you cut into it, hold the two pieces together, they’ll reattach! Eventually.
2015年 在德国莱布尼兹高分子聚合物研究所的科学家创造了这种科技
Scientists at Germany’s Leibniz Institute of Polymer Research created this technology
希望用于发明能够自行修复的 汽车和卡车轮胎
in 2015, in the hopes of inventing car and truck tires that can fix themselves.
他们通过替换目前轮胎中的化学成分来实现这个目的
And they did it by making one pretty simple switch in the chemistry of the tires we currently use.
这些轮胎实际上并不是纯粹的橡胶
Tires, it turns out, aren’t just pure rubber.
相反 硫磺通常都会被添加到橡胶中 使其分子结合的更加紧密
Instead, sulfur is usually added to the rubber, to make its molecular bonds stronger.
这使得橡胶更加坚固耐用
This makes the rubber tough enough to support your car.
下面我们要说的是 一旦这些结合断裂 例如切割或者刮擦
The downside is that, once those bonds break — from something like a cut or a scratch
它们将永远断裂
— they’re broken forever.
你永远不能将这些分子重新连接到一起
You can’t just bond those molecules back together.
但是 研究人员可以通过成对的带电分子或离子替换其中的硫磺使这些橡胶自行修复
But the researchers were able to make rubber self-heal by replacing the sulfur in the rubber
叫做丁基咪唑鎓盐 和 溴化物
with a pair of charged molecules, or ions, called butyl imidazolium and bromide.
丁基咪唑鎓盐拥有正电荷 总是伴随着一个负电荷的
Butyl imidazolium has a positive charge, and it’s always accompanied by a negatively
溴化物 就像盐粒中的钠离子和氯离子
charged bromide, just like the ions of sodium and chloride that you find in table salt.
这些离子总是趋于成对的结合在一起 形成一个较大的群体
And just like in salt, these pairs of ions tend to bond to other pairs, to form big groups.
这就意味着 一个离子对连接一个橡胶分子可以粘合另一个离子对链接一个 橡胶分子
That means that an ion pair attached to one rubber molecule can stick to a pair on another rubber molecule.
而且他们结合使用的是离子级的链接
And they bind using strong, ionic bonds.
这种级别的结合可以把橡胶分子绑定一起 强化材料强度
These ionic bonds hold the rubber molecules together and strengthen the material, just
就像用硫磺固定处理一样
like the sulfur bonds did.
目前为止讲了非常多的好处
So far, so good.
但是对于离子绑定非常关键的是他们容易断裂和重组
But the crucial thing about ionic bonds is that they can easily break and reform,
就像夹克上的纽扣一样
just like the snaps on a jacket.
所以 当研究人员切割新型橡胶时 链接断裂了
So when the researchers cut into strips of their new rubber, the ionic bonds broke.
但是 当把他们拼接到一起时可以再次结合成新的
But, pushing the two pieces together allowed the pairs find each other again
离子链接
and form new ionic bonds.
从而快速愈合研究人员通过加热 挤压附近的分子来帮助
To heal the cut quickly, the scientists added heat, to jostle the molecules around and help
独立的物体相互结合
lonely pairs bump into each other.
并且新的结合非常紧密足够将两片橡胶结合在一起
And the renewed bonds were strong enough to hold the two pieces of rubber together!
科学家现在正在试图制造离子橡胶 不用加热就可以恢复 轮胎可以
Scientists are now trying to make ionic rubbers that heal without heat, so a tire can fix
在没气之前就可以自行修复
itself before it goes flat.
在这段时间里 另一部分研究人员通过不同的方法
And in the meantime, other researchers are taking a totally different approach
来制造自我修复的塑料
to make self-healing plastics.
这个想法是在塑料和油漆中混合一些
The idea here is to mix tiny, tiny packets of a special glue, called a healing agent,
非常细小的特殊胶水包 叫做修复因子
into plastics and paints.
当塑料出现裂缝 这些胶水包就会打开
Then, when the plastic cracks, the packets will open up,
释放胶水去密封这些裂缝
and spill out glue to seal up the crack.
问题是 大量的胶水需要空气来干燥或者空气中的水
The thing is, a lot of glues need either air to dry,
来开始执行或修复
or water from the air in order to set, or cure.
但是科学家不能总是依靠周围有空气或水
But scientists can’t rely on air or water always being around,
来进入非常细小的裂缝
to get into every tiny crack.
所以 他们加入了第二种化学物质来帮助修复因子进行修复
So they add a second chemical that helps the healing agent cure.
在伊利诺斯州大学的一队科学家运用一种叫HOPDMS的修复因子
A team at the University of Illinois tried this, using a healing agent called HOPDMS.
他的分子拥有很长的链叫做高分子聚合物 每一个分子的末端都有一个氢氧基对
***Its molecules come in long chains, called polymers, and on each end there’s a hydrogen-oxygen
叫做羟基组
pair, called a hydroxyl group.
研究人员在这些像沙粒大小的胶水包中
Then, the researchers added tiny packets — each about the size of a grain of sand — filled
添加了这种化学物质作为固化因子 叫做DMDNT
with a second chemical that works as a curing agent, called DMDNT.
当塑料破裂 这些化学物质就会从胶水包中释放出来
When the plastic breaks, the chemicals leak out of their packets, and they mix.
在固化因子开始行动时混合在一起
That’s when the curing agent sets into action.
它与HOPDMS产生反应 通过打断每一个链接末尾的羟基组
It reacts with HOPDMS in such a way that it breaks off a hydroxyl group from one end of
使得两个链接可以结合在一起
each chain, so that two chains can join together!
一个单独的DMDNT分子能够不停地结合数以千计的高分子聚合物
A single molecule of DMDNT can stitch up thousands of polymers without stopping, so the glue
这些胶水最终大部分是由修复因子组成的
you wind up with is mostly made up of healing agent.
形成这些微小链接听起来似乎是很小的变化 但是效果却非常巨大
Making these little chains longer might sound like a small change, but the effect is huge:
这些较长的聚合物纠缠在一起形成结 阻止分子自由活动
These longer polymers get tangled into knots that prevent the molecules from moving freely.
并且固化修复因子成为固体
And that hardens the healing agent into a solid.
因为塑料中含有所有修复必须的物质 能够在任何地方
Because the plastic has everything it needs to heal, it can heal anywhere,
快速可靠地修复
quickly and reliably.
科学家们已经应用这项技术制造塑料涂层
Scientists have already used this technique to make a plastic coating that basically acts
像自我修复漆
like self-healing paint.
在一次测试中 研究人员将那些微小胶水包添加到塑料混合物中
In one test, researchers added those tiny packets into a plastic mixture that they painted
涂抹到钢铁上 看是否能防锈
on steel, to see if it would prevent rust.
随后用刀子把涂层刮开 让涂层自行修复一天
Then they scraped the coating with a razor blade and let the coating heal for a day.
之后将金属浸入腐蚀性盐水中放置几天
After that, they dunked the metal in corrosive saltwater and let it sit there for a few days…
没有生锈
and it emerged rust-free!
现在 科学家正在把这项技术应用于其他金属中
Now, scientists are looking at putting this technology to work in other materials, embedding
把这些强力胶水包植入混凝土和金属中 所以日常生活中的所有物品
these powerful packets in concrete and metal, so that just about anything in your life can
都能更久更安全的使用
last longer and be safer to use.
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