99免费在线观看I国内亚洲精品I深夜免费福利视频I男女激情免费网站I日产乱码一二三区别在线I97超碰在线视

"The scientific name of nylon is polyamide, which is also a general term for thermoplastic resins. There are many kinds of nylon, with large production capacity and wide application. And its molecular structure is nylon fiber.

Nylon has good comprehensive properties, and its fiber strength is 1-2 times higher than that of cotton. It has the significant advantage of replacing steel, iron, copper and other metals with plastics in production and manufacturing, and is an important engineering plastic.