Are your car’s bumpers riddled with scars from encounters with tight parking spaces? Did the furniture movers [--1--] your floor? Wouldn’t it be great if those marks could just disappear? Well, thanks to the magic of chemistry, maybe such nicks will soon be [--2--]. Because scientists have produced a material that can actually heal itself, work published in the journal Nature.

The paint on your car, the varnish on your floor, even the nylon in your [--3--] are all polymers—extremely long chains of molecules held together by strong chemical bonds. But this new material isn’t like any old polymer. It’s a supramolecular polymer, made of smaller molecules held together by weak [--4--] with metals, which act like a kind of molecular Velcro.

When this polymeric material is torn, exposing it to an intense beam of UV radiation breaks the weak bonds in and around the tear. That disruption allows the material to flow like a liquid, which then heals the wound. When the light is switched off the polymer resolidifies, leaving the surface as good as new. Which would be good news for your bumpers. And for your teenager, who won’t have to explain the [--5--] on your car.
【视听版科学小组荣誉出品】
scratch nipped panty hose interactions ding
可"自愈"的"外衣" 面对众车林立的停车场, 你的"宝马"的保险杆是不是经常"伤痕累累"? 搬家的时候搬家工人有没有刮坏你的地板? 要是这些刮痕能消失的话是不是很棒呢? 放心, 有我们化学魔术师, 这些小"伤痕"会迅速消失. 因为科学家发明了一种可以"自愈"的材料, 研究成果发表在<自然>期刊上. [Mark Burnworth 等, "光学可自愈超分子聚合物"] 我们爱车上的油漆, 地板上的清漆, 甚至穿的尼龙丝袜都是聚合物---由强化学键组在一起的超长分子链. 但是这种新材料却不是之前任何一种聚合物. 它是超分子聚合物, 由与金属间的弱力【注1】组在一起的更小的分子构成, 有点像分子组成的维可牢【注2】. 当这种聚合物材料被划开后，用高强度紫外线照射,破坏划痕里面和周边的弱化学键. 这种破坏让材料像水一样流动以达到"治愈伤口"的目的. 关掉紫外线后,聚合物重新固化, 表面则完好如初. 这个成果将是你的保险杠的福音, 当然, 也是那些刮伤你的车的小孩的福音. 注1： 弱力，四种基本力中第二弱的、作用距离非常短的一种力。它只作用于自旋为1/2的物质粒子，并制约着放射性现象。而对诸如光子、引力子等自旋为0、1或2的粒子不起作用。 注2： 维可牢，一种尼龙搭扣，也叫“魔术贴”。