Is the production process of polypropylene hollow filament complex?

The production process of polypropylene hollow filament is more complex, mainly including the following key steps:

Raw material preparation: The selection of high-purity polypropylene slices as raw materials, according to product performance requirements, may also need to add appropriate additives, such as antioxidants, ultraviolet absorbers, etc., to improve the performance of polypropylene hollow fibers. The quality of raw materials is crucial to the performance and quality of the final product and requires strict inspection and screening of raw materials.

Melt extrusion: Pretreated polypropylene slices are added to the extruder and melted by heating. In the extruder, parameters such as temperature, pressure and screw speed need to be precisely controlled to ensure good flow and uniformity of the polypropylene melt. The melt is then extruded through a specially designed spinneret to form a bundle with a hollow structure. The design and machining precision of spinneret have a decisive influence on key indexes such as hollow degree and diameter uniformity of polypropylene hollow wire.

Cooling molding: The strands extruded from the spinneret are cooled and solidified in the air or through a specific cooling medium (such as a cold water bath) to form a preliminary polypropylene hollow filament. The cooling process requires strict control of the cooling speed and cooling uniformity to avoid defects in the tow, such as cavity deformation and uneven wire diameter.

Tensile orientation: In order to improve the strength and other mechanical properties of polypropylene hollow filament, it is necessary to carry out tensile orientation treatment on the cooled tow. The stretching process is usually carried out in stages under different temperature and speed conditions, so that the polymer chain is oriented in the direction of the fiber axis, thereby improving the crystallinity and orientation of the fiber. The precise control of parameters such as drawing multiple, drawing temperature and drawing speed is very important to obtain the ideal fiber properties.

Crimp shaping: According to the use and performance requirements of the product, the polypropylene hollow wire after stretching is crimp shaping treatment. Crimp can increase the binding force and volume between the fibers, improve the processing performance and service performance of the fibers. Crimp setting usually adopts mechanical crimp or chemical crimp method, by controlling crimp process parameters, such as crimp temperature, crimp pressure, crimp time, etc., so that the fiber can obtain a stable crimp shape.

Post-treatment: The post-treatment process includes washing, drying, oiling and other steps. Water washing can remove impurities and residual additives on the fiber surface; Drying is to remove the water in the fiber, improve the stability and quality of the fiber; Oil treatment can improve the softness, smoothness and antistatic properties of the fiber, which is conducive to subsequent processing and use.

In the entire production process, it is necessary to use high-precision production equipment and advanced automated control systems to accurately control each process parameter to ensure the stability and consistency of product quality. At the same time, the production process also needs to carry out online testing and offline testing of the product, and timely find and solve the problems in the production. Therefore, the production process of polypropylene hollow wire is relatively complex, and the production technology and management level are high.

Shanghai Jinci Industrial Co., Ltd. was established in March 2006, including polypropylene general strong yarn, polypropylene high strength yarn, polypropylene anti-aging yarn, polypropylene twist yarn, polypropylene hollow yarn, polypropylene fluorescent silk, polypropylene luminous silk, polypropylene flame retardant silk, polypropylene air change yarn, polypropylene waterproof yarn, etc. Color based, with a number of fast prototypes, according to requirements, accurate, timely tailored products for customers. Since the factory opened, it has developed and produced tens of thousands of products with different specifications and colors. Wide range of product densification. Raw silk products 300D-3000D.