近年来，我国高分子材料工业发展迅速，各类高分子材料产品层出不穷，逐渐渗透到各个领域，大量代替钢铁、有色合金等，创造了极好的经济效益。早些年，提升机上衬垫用牛皮制成，并且还只能用牛背上的那一块，用量相当大，成本很高。人们试着对其进行替代，先用铝材，效果不佳? In recent years, the rapid development of China’s polymer materials industry, an endless stream of various types of polymer materials, and gradually penetrate into various fields, replacing a large number of steel, nonferrous alloys, and create excellent economic benefits. Earlier years, the elevator liner was made of cowhide, and it was only used on the back of a cow, which was quite large and costly. People try to replace it, first with aluminum, poor results?