What Causes The Surface Of Masterbatch To Be Uneven?

What causes the surface of masterbatch to be uneven? Due to raw materials, formula, processing technology and other reasons, the masterbatch mixing and dispersion are uneven, and the surface of the masterbatch is rough. In severe cases, there will be serious poor dispersion color spots on the surface of the masterbatch.

1. Whether the dispersibility of the pigment is good. If the pigment molecules are too hard, they will be poorly dispersed in the plastic, resulting in an uneven surface.

2. Whether the quality of the dispersant (low molecular weight polyethylene wax) is qualified and the dosage is appropriate. If some low molecular weight polyethylene wax is mixed with paraffin, or it is a high-density low molecular weight polyethylene wax, it will affect the dispersibility of the pigment.

3. Improper wetting treatment of the pigment. No matter what means are used, a masterbatch product with good dispersion and smooth surface cannot be obtained.

What should I do if the surface of the masterbatch is not smooth? First, check whether the extrusion temperature is appropriate. If the extrusion temperature is too high or too low, the surface will become rough, so the extrusion temperature should be adjusted.

Some masterbatch manufacturers are obsessed with the appearance of masterbatch, which reduces the performance of masterbatch. Some even increase the proportion of stearate added to 5% or higher. However, it is this pursuit of the so-called “appearance” that leads to excessive addition of low molecular weight components, which will quickly reduce the total viscosity of the dispersion system, thus seriously affecting the dispersion results due to insufficient viscosity shear; in addition, the addition of too much low molecular weight/low melting point substances will also affect the physical properties of the terminal product to a certain extent.