In the molding process of plastic products, almost everyone has used black masterbatch for dyeing, anti-aging, conductive products and so on. However, various problems often appear during use, which bother us. Today, the editor will discuss some issues of common concern to everyone, hoping to bring you gains.
5: What dispersant will be used for carbon black masterbatch? Mainly divided into two types: organic dispersant and inorganic dispersant. The high-grade black masterbatch uses organic dispersant, which is mainly used for plastic products with high environmental requirements, such as drip irrigation products. Low-grade black masterbatch uses inorganic dispersant, commonly calcium carbonate. It can be judged from the packaging of the masterbatch that if there is only half a bag of 25 kg, inorganic dispersant must be used; the full bag is black masterbatch with organic dispersant. The use of inorganic dispersants can greatly reduce the cost of black masterbatch, but the fatal thing is that calcium carbonate can accelerate the aging of plastic products.
6: Does the black masterbatch need processing aids? Of course it needs. A smooth process requires the selection of the correct antioxidants, internal lubricants, external lubricants, modifiers and antistatic agents.
7: What are the processing methods for black masterbatch? There are three processing methods: single screw method, twin screw method and close love method. Single-screw method: After mixing the materials with a mixer, they are pelletized by a single-screw extruder. Generally, the carbon black concentration is 18-20%. The process is backward and the environmental conditions of the production site are poor. It is an eliminated process and is not excluded. Some start-up small factories still use this method for processing. Twin-screw method: After mixing the materials with a mixer, the twin-screw extruder is used for stranding or water ring granulation. Due to the limited mixing capacity of the twin-screw machine, the masterbatch generally has a carbon black concentration of 25-32%. Internal mixing method: After mixing the materials with a mixer, adding them to the internal mixer for kneading, they are fed into the twin-screw extruder from the feeder, and pelletized by water ring or underwater. The masterbatch generally has a carbon black concentration of 40- 45%.
8: Does the processing method affect the performance of the masterbatch? Definitely. Among them, the internal mixing method can improve the carrier's bearing capacity for carbon black, and at the same time, the carbon black can enter the carrier more uniformly. Take advantage of the mechanical kneading of the internal mixer to crush the agglomerated particles, greatly reducing the agglomerated particle size of carbon black particles. The particle size and distribution of carbon black in the masterbatch are uniform, which cannot be replaced by the other two methods.