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Network processing technology is a new technology developed and realized in industrialization in the 1970s. Network filaments are also known as pulp-free yarns, and high-strength pp network yarn are mainly used as warp yarns. In the past, the non-web filaments used as warp yarns needed sizing, and polypropylene had a strong sense of plastic wax and was difficult to sizing. If twisting is used, production efficiency will be greatly reduced. Therefore, the high-strength pp network yarn has become the main method for polypropylene to make warp yarns.