Methods to improve the hardness of PVC pipes

March 18, 2024

How to improve the hardness of the PVC pipe produced if it cannot meet the standard? Mainly considering raw materials and formulas. Please refer to the following for details:

1. The precipitation volume of filling material (calcium powder) should preferably be within 2.6-3.0. To balance both hardness and tear strength, calcium powder should not exceed 25 parts. In addition, an appropriate amount of nano calcium can be added to improve the strength;

2. The selection of stabilizers is crucial. Stabilizers (lead salt stabilizers, calcium zinc stabilizers, etc.) should have good thermal stability and stable internal and external lubrication balance. Do not use stabilizers that are too cheap

3. If the stability is insufficient, a small amount of metal soap can be compensated;

4. The amount of CPE used should not be too large, as excessive CPE usage can affect the hardness of the pipe; CPE should be selected with high molecular weight, standard chlorine content, no more than 35%, and no residue;

5. Lubricants cannot be used too poorly, they must be good, and PE wax is the worst for external lubrication. The total dosage is about 1.5 parts, not too much, so that when the product deforms under external forces, the PVC molecular chain connection is not easily damaged;

6. In terms of modification, CPE+ACR system, ACR+MABS system, or CPE+MABS system can be selected.

7. Titanium dioxide can affect tear strength, so it is recommended to choose a fine one.