英语听力文摘 English Digest 197、特氟隆为何如此滑

　　Why Teflon Is Slippery？
1954年，法国工程师马克·格雷瓜尔(Marc Gregoire)的妻子柯莱特(Colette)突发奇想，觉得丈夫用来涂在钓鱼线上防止打结的不粘材料特氟龙(Teflon)如果可以用在煎锅上，效果一定不错。拯救了无数现代家庭主妇的“不粘锅”由此诞生。不过，1938年被罗伊·普朗克特(Roy Plunkett)发明出来的聚四氟乙烯(特氟龙是商品名)最早的用武之地，却是举世闻名的“曼哈顿计划”。
特氟龙英文全称为Polytetrafluoroetylene，简称Teflon、PTFE、F4等。特氟龙高性能特种涂料是以聚四氟乙烯为基体树脂的氟涂料，英文名称为Teflon，因为发音的缘故，通常又被称特氟龙分子式图片之为铁氟龙、铁富龙、特富龙、特氟隆等等（皆为Teflon 的译音）。特氟龙（铁氟龙）涂料是一种独一无二的高性能涂料，结合了耐热性、化学惰性和优异的绝缘稳定性及低摩擦性，具有其他涂料无法抗衡的综合优势，它应用的灵活性使得它能用于几乎所有形状和大小的产品上。

　　Teflon is the trademark¹ name for PTFE, a type of plastic.
If you own any non stick cookware, then you probably use PTFE on a daily basis. You might not realize, as you fry your morning eggs, that PTFE is one of the most slippery materials that can be manufactured. It’s about as slippery as wet ice.
What makes Teflon so slippery?
Teflon is chemically similar to another, more common plastic: polyethylene, the material used to make plastic bags and other plastic containers.
Chemically, polyethylene is made from long chains of carbon atoms with hydrogen atoms bonded² to the sides of the chains. To make Teflon, the hydrogen atoms of polyethylene are replaced by fluorine atoms.
Fluorine Atoms
It’s the fluorine atoms that give Teflon its slipperiness. Fluorine atoms are physically³ bigger than hydrogen atoms. Their large size makes them huddle⁴ around the central carbon chains in a much tighter formation.
This tight formation works like a kind of chemical armor, protecting the carbon atoms which in turn hold the molecule⁵ together.
Chemical Teamwork
This chemical teamwork between carbon and fluorine makes Teflon extremely chemically stable, and it’s this chemical stability that makes Teflon so slippery.
Foreign substances, like a frying egg, can find no chemical foothold on the fluorine armor, so they simply slide away.
Never Sticky
Getting this slippery substance to stick to a frying pan is a bit of a trick.
Teflon is broken into a fine powder and suspended in water. The pan is then thoroughly⁶ cleaned, then roughened by sand-blasting. The Teflon is sprayed onto the pan and baked, causing it to fuse together and lock onto the roughened surface of the pan.
As long as you don’t scratch this protective coating, years worth of fried eggs, melted cheese, burned milk even toffee will slide away effortlessly.

1 trademark   

n.商标；特征；vt.注册的…商标

参考例句：

• The trademark is registered on the book of the Patent Office.该商标已在专利局登记注册。
• The trademark of the pen was changed.这钢笔的商标改了。

2 bonded   

n.有担保的，保税的，粘合的

参考例句：

• The whisky was taken to bonded warehouses at Port Dundee.威士忌酒已送到邓迪港的保稅仓库。
• This adhesive must be applied to both surfaces which are to be bonded together.要粘接的两个面都必须涂上这种黏合剂。

3 physically   

adj.物质上，体格上，身体上，按自然规律

参考例句：

• He was out of sorts physically,as well as disordered mentally.他浑身不舒服，心绪也很乱。
• Every time I think about it I feel physically sick.一想起那件事我就感到极恶心。

4 huddle   

vi.挤作一团；蜷缩；vt.聚集；n.挤在一起的人

参考例句：

• They like living in a huddle.他们喜欢杂居在一起。
• The cold wind made the boy huddle inside his coat.寒风使这个男孩卷缩在他的外衣里。

5 molecule   

n.分子，克分子

参考例句：

• A molecule of water is made up of two atoms of hygrogen and one atom of oxygen.一个水分子是由P妈̬f婘̬ 妈̬成的。
• This gives us the structural formula of the molecule.这种方式给出了分子的结构式。

6 thoroughly   

adv.完全地，彻底地，十足地

参考例句：

• The soil must be thoroughly turned over before planting.一定要先把土地深翻一遍再下种。
• The soldiers have been thoroughly instructed in the care of their weapons.士兵们都系统地接受过保护武器的训练。