4 indicators needed for polyethylene wax for color masterbatch

Polyethylene wax (PE wax), also known as polymer wax for short. It is widely used because of its excellent cold resistance, heat resistance, chemical resistance and wear resistance. In normal production, this part of wax can be added directly to polyolefin processing as an additive, and it can increase the gloss and processing performance of the product.

1. High thermal stability.
The polyethylene wax used for masterbatches must withstand the processing temperature well during the manufacture of masterbatches and the molding of coloring products. If it vaporizes or decomposes, it will have a negative impact on the masterbatch or coloring products. The processing temperature of polyolefin masterbatches and coloring products is generally between 160-280°C. The general polyethylene wax can withstand in this temperature range, while the low molecular matter and paraffin wax produced by HDPE polymerization are difficult to withstand. We conducted isothermal thermal weight loss test on paraffin wax with melting point of 60℃, we found that at 200℃, paraffin wax lost 9.57% of its weight in 4 minutes and 20% of its weight in 10 minutes. Therefore, paraffin wax is not suitable for color masterbatch production only from the viewpoint of heat resistance.

2. Proper molecular weight.
The molecular weight of commonly used polyethylene wax is generally around 1000-4000. In the test for the hard-to-disperse carbon black, the polyethylene wax with the same molecular weight distribution was chosen, and it was found that the dispersion ability of the wax on carbon black was further improved with the increase of molecular weight.

3. Narrower molecular weight distribution.
Molecular weight distribution has a certain influence on the dispersion performance of polyethylene wax. The wax with narrow molecular weight distribution has higher dispersion rate compared with the wax with wide molecular weight distribution, which shows that the polyethylene wax produced by polymerization is better than the cracked one.

4. Stronger dispersion ability.
Polyethylene wax low melting point can improve the dispersion of pigment, and the good or bad dispersion of pigment directly determines the coloring ability of masterbatch. If the pigment is well dispersed, the coloring power of the masterbatch is high. Therefore, the coloring power can be used to characterize the dispersion ability of polyethylene wax to pigments.