Understand thirteen related knowledge of black masterbatch

1. What is the composition of the black masterbatch? The materials that make up the black masterbatch are: A. Carbon black; B. Carbon black carrier; C. Carbon black wetting agent; D. Carbon black dispersant; E. Other processing aids.

2. What kind of carbon black is used in the black masterbatch?

According to international classification, there are more than 30 varieties in China. Mainly divided into two categories: rubber and non-rubber. Among the carbon blacks for rubber, wear-resistant carbon blacks are mainly used, which can effectively improve the wear resistance of rubber tires. Among the carbon blacks for non-rubbers, there are only a few carbon blacks that can be used as black masterbatch. Channel carbon black is the most widely used in plastics, mainly due to its abundant source, high purity and small particle size. Among them, it is divided into high pigment carbon black (particle size 9-17mm), medium pigment carbon black (particle size 18-25mm) and low pigment carbon black (particle size 26-37mm). Due to the different varieties of carbon black, the price varies greatly. Carbon black particles seldom exist as primary particles due to their own reactivity, and almost all exist as agglomerated particles with a certain range of particle diameters.

3. What is the carbon black carrier? The carrier is the substance that carries the carbon black. Generally, what raw materials are used in plastic products, and what raw materials are used in the carrier. The black masterbatch manufactured in this way has better compatibility with plastic raw materials. Such as: PS (polystyrene) plastic products, the black masterbatch carrier used is PS. For polyethylene plastic products, the carrier is polyethylene.

However, LDPE (High Pressure Polyethylene) is generally selected because LDPE has the strongest carbon black carrying capacity and good processing performance. Other polyethylene HDPE and LLDPE can only produce low-concentration black masterbatch. For PP (polypropylene) plastic products, only black masterbatches with PP and LDPE as carriers can be used, but black masterbatches with HDPE, LLDPE and other plastics as carriers cannot be used. Of course, there is also a black masterbatch with recycled materials as a carrier.

4. Why does carbon black need a wetting agent? According to Coating Online, the specific gravity of carbon black is about 2g/cm. Due to the small particle size of carbon black, the apparent density is very small, and it appears fluffy and seems very light. For smooth processing, the carbon black must first be wetted. The choice of wetting agent is very critical. In order to reduce costs, there are not a few companies that use a large amount of products such as white oil or paraffin, which will seriously affect the strength of the processed products.

5. What dispersants will be used for carbon black masterbatch? Mainly divided into two types: organic dispersant and inorganic dispersant. The high-grade black masterbatch uses organic dispersants and is mainly used for plastic products with high environmental requirements, such as drip irrigation products. Low-grade black masterbatch uses inorganic dispersant, and calcium carbonate is commonly used. 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 has the effect of accelerating the aging of plastic products.