Does POM black regenerated particles have good fluidity during processing?
Publish Time: 2025-05-19
POM (polyoxymethylene) is an engineering plastic widely used in industrial manufacturing, and is favored for its excellent mechanical properties, wear resistance and chemical corrosion resistance. With the increasing awareness of environmental protection, more and more companies have begun to use recycled plastics to reduce production costs and reduce environmental pollution. Among them, as a common recycled material, whether POM black regenerated particles have good fluidity during processing has become an important factor affecting product quality and production efficiency.
1. Basic characteristics of POM black regenerated particles
POM black regenerated particles are made by recycling waste POM products through crushing, cleaning, melting and regranulation. Compared with the original POM raw materials, the physical and chemical properties of the recycled particles may change to a certain extent, such as a wider molecular weight distribution and a decrease in thermal stability. However, since POM itself has a higher degree of crystallinity and a lower melt viscosity, its basic rheological properties are still relatively stable even after recycling and reuse. This allows POM black regenerated particles to maintain a certain degree of fluidity during processing, making them suitable for molding processes such as injection molding and extrusion.
2. Main factors affecting the fluidity of POM black regenerated particles
During the processing, the fluidity of POM black regenerated particles is affected by many factors, mainly including temperature, shear rate, mold design and the degree of dryness of raw materials. First, temperature is one of the key factors that determine the fluidity of the melt. The melting point of POM is usually between 160℃ and 180℃. Appropriate heating can reduce the viscosity of the melt and improve the fluidity. However, if the temperature is too high, it may cause material degradation, which in turn affects the quality of the finished product. Secondly, the shear rate also has a significant effect on the fluidity of the melt. Under high-speed shear conditions, the POM melt will show lower viscosity, which is conducive to filling complex molds. In addition, the rationality of the mold design will also affect the filling effect of the melt. Reasonable runner and gate design can help improve the flow behavior of the recycled particles. Finally, the degree of dryness of the raw materials cannot be ignored. POM has strong hygroscopicity. If the recycled particles are not fully dried, bubbles or silver streaks are easily generated at high temperatures, affecting the appearance and mechanical properties of the product.
3. Fluidity performance of POM black regenerated particles in different processing technologies
In practical applications, POM black regenerated particles are mainly used for injection molding and extrusion molding. During the injection molding process, good fluidity means that the melt can quickly fill the mold cavity and reduce the occurrence of defects. Studies have shown that under appropriate temperature and pressure conditions, the melt index (MFI) of POM black regenerated particles can reach a high level, enabling it to meet the molding requirements of most injection molding products. At the same time, since the recycled particles may contain a small amount of impurities, the processing parameters should be controlled during use to avoid clogging the nozzle or affecting the surface finish of the product. In terms of extrusion molding, the fluidity of POM black regenerated particles determines whether it can pass through the die head evenly to form a continuous product. Experiments show that as long as the screw speed and temperature settings are reasonably adjusted, the recycled particles can show fluidity close to that of the original material during the extrusion process, which is suitable for the production of pipes, plates and other products.
4. Optimization strategy for improving the fluidity of POM black regenerated particles
In order to further improve the fluidity of POM black regenerated particles, enterprises can take a series of optimization measures. First, use advanced recycling technologies such as low-temperature crushing and high-efficiency melt filtration in the regeneration process to reduce the impurity content and improve the uniformity of particles. Secondly, the melt viscosity can be reduced and its filling capacity in the mold can be improved by adding an appropriate amount of lubricant or plasticizer. In addition, it is also a necessary step to fully dry the recycled particles before processing to prevent moisture from affecting the melt stability. Finally, combined with the specific processing equipment and product requirements, the temperature, pressure, shear rate and other parameters are reasonably set to make the recycled particles flow and form in the best state.
In summary, POM black regenerated particles have good fluidity during processing, especially under appropriate processing conditions, its melt fluidity can meet the production requirements of most engineering plastic products. Although the recycled particles are slightly inferior to the original materials in some properties, these shortcomings can be fully compensated by optimizing the recycling process and adjusting the processing parameters.
