"Tiangong Kaiwu" is an ancient book that records many crafts and technologies. I will use "Expanded Polytetrafluoroethylene" (expanded polytetrafluoroethylene) as the core to create a classical Chinese style in imitation of its style.

Expanded polytetrafluoroethylene is a thing in the world, with a wide range of categories, while expanded polytetrafluoroethylene is unique. Its weight is light and strong, soft and tough, and its various physical properties are wonderful.

The original production of this thing is complex and skillful. The fluorite ore is mined and smelted many times to obtain a pure fluorine source. And in a delicate way, it is polymerized into the embryo of polytetrafluoroethylene, and then applied clever techniques to make it expand. In the meantime, the control of the fire and the ingenuity of the technique are all about success or failure.

And its achievements are widely used. In the genus of equipment, it can reduce friction and drag, make the operation smooth and durable; in protective equipment, it can withstand water and fire, isolate all kinds of erosion, and ensure people's safety. As for civil engineering, it can resist wind and rain, withstand the wear and tear of time, and protect the house for a long time.

Looking at this, the magic of creation and the delicacy of human labor are all gathered in this thing. Its benefits to the people and benefit the country are indeed rare and good materials in the world. Later scholars should study this technique in detail, introduce new ones, and benefit the world.