国产麻豆午夜三级精品-怡春院在线视频-国产精品19乱码一区二区三区-日本精品视频-情侣酒店偷拍一区二区在线播放-国产一区啪啪-性少妇xxxxx-可以在线观看的av网站-韩国伦理中文字幕-国产美女被遭强高潮网站下载-黄色午夜网站-特黄特色大片免费播放器下-天天综合日韩-国产伦精品一区二区三区照片-久久精品国产99久久久小说-少妇与黑人一二三区无码-成年人福利-尤物精品视频在线观看-日本一区二区视频-黄色大片国产

"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.