The role of wax compound lubricant in the extrusion of rigid PVC pipes

The role of paraffin polyethylene wax compound lubricant in the extrusion of rigid PVC pipes

Common rigid PVC pipe formulations:

Component addition amount

PVC resin: 100.0 phr

Tin Stabilizer: 0.30 – 1.00 phr

Paraffin: 0.60 – 1.50 phr

Polyethylene Wax: 0.00 – 0.30 phr

Calcium stearate: 0.40 – 1.50 phr

Calcium carbonate: 0.00 – 5.00 phr

Titanium dioxide: 0.50 – 3.00 phr

Processing aid: 0.00 – 2.00 phr

In the formula, we can see the figure of paraffin wax and polyethylene wax. Paraffin wax has been used as a lubricant for rigid PVC for more than 40 years, but the softening point of paraffin wax is relatively low. During high temperature processing, paraffin wax is volatile and has poor dispersibility, which will result in a very bright PVC pipe. Poor, and there will be many stains on the surface, and the anti-sticking effect is poor. Therefore, it is necessary to add polyethylene wax to neutralize the lubricating effect of paraffin wax.

Polyethylene wax used for PVC pipes has the following functions:

Prevents rigid PVC from degrading when heated and sheared.

Increase mobility and control fusion

In the process of pipe production, the lubrication effect will be adjusted according to the plasticization state of the material.

Promote the dispersion of fillers, improve the surface gloss of the pipe, and make the pipe feel smooth

The paraffin polyethylene wax based lubricant is the key to the advancement of rigid PVC pipes to high quality.