What is pvc compounding?

There are many different pvc compounds to choose from. A special composite should be able to provide a plastic compound to meet the needs of your product, whether it is ready-made or specially designed for you. A compositor should have technical experts who can work with you to provide solutions and service support to meet your needs. In this article we will find more about the pvc compounding granules making extruder.

 

The following knowledge points are listed below:

l  Basics about pvc compounding

l  How to make pvc compounds formula

 

Basics about pvc compounding

Pvc compounds are thermoplastic polymers customized by mixing additives and/or colors so that the material (usually in pellet form) is ready for injection, blow molding or extrusion processing and made into final parts for specific applications. For example, polypropylene (PP) can be reinforced with reinforcing and reinforcing additives to achieve a higher level of performance. Polyvinyl chloride (PVC) polymers can be enhanced by adding raw materials that are flexible and easy to process, and can provide flame retardancy and UV stability. Almost every type of thermoplastic is provided as a special compound, and there are many different types of pvc compounds because there are different plastic products for different markets.

 

How to make pvc compounds formula

(1)      polyvinyl chloride resin

In order to obtain fast and uniform plasticization, suspension type loose resin should be used for pvc recycling compounding extruder.

--Resin for double-wall corrugated pipes, especially resins with good molecular weight distribution and good impurity quality, can reduce "fish eyes" in the pipe and avoid pipe shrinkage and pipe wall cracking.

--The resin used for water supply pipes should be "sanitary", and the residual amount of vinyl chloride in the resin should be within 1mg/kg. In order to ensure the quality of pipes and reduce the rejection rate, the source of resin should be stable.

(2)      stabilizer

At present, the main heat stabilizers of pvc compounds used are: metal soap, composite lead salt stabilizer, rare earth composite stabilizer, and organic tin stabilizer.

Stabilizers containing heavy metals (such as lead, barium, cadmium) are harmful to human health, and the use of these stabilizers in water supply pipeline formulations is limited. In the single-screw extrusion process, the thermal history of the material is longer than that of the twin-screw extrusion process, and the former uses more than 25% of the stabilizer. The head temperature of the double-wall corrugated pipe is relatively high, the material stays in the head for a long time, and the amount of stabilizer in the formula is more than that of the ordinary pipe formula.

(3)      filler

The role of filler is to reduce costs. Try to use ultra-fine active fillers (higher prices). The number of pipes is greater than the number of profiles. If the amount of filler is too large, the impact resistance will decrease, and the pressure resistance of the pipeline will also decrease.

Therefore, in chemical pipelines and water pipes, the number of fillers is within 10 parts. Drain pipes and cold-formed threaded casings can use more fillers and increase the amount of CPE to change the impact performance.

For pipes with lower performance requirements for pipes and rainwater pipes, the amount of filler can be large, but the wear of the twin-screw extruder is more serious.

(4)      modifiers

Processing modifier: ordinary pipes can be used less or indispensably, and corrugated pipes and thin-walled pipes are more frequently used.

Impact modifier: less than the amount of profile, there are two reasons: Performance, low temperature resistance, tensile strength. Also, the cost.

Other additives, coloring agents, etc. As an anti-aging agent, titanium dioxide must be added to the profile.

Now you know what pvc compounding extruding machine is.