Comparison between Calcium Carbide Method and Ethylene Method for PVC Production

Categories:

NEWS

Author:

Papageno Group

Origin:

Original

Time of issue:

2023-12-29

When it comes to the production of Polyvinyl Chloride (PVC), two prominent methods stand out: the Calcium Carbide Method and the Ethylene Method. Understanding the distinctions between these approaches is crucial for industries seeking to optimize their processes and meet specific product requirements.

Comparison between Calcium Carbide Method and Ethylene Method for PVC Production

Price Factors:

The cost of Calcium Carbide Method PVC is primarily determined by electricity costs, while the cost of Ethylene Method PVC is mainly influenced by international crude oil prices.

Quality Differences:

Calcium Carbide Method PVC has a water content four to five times higher than that of Ethylene Method PVC. The impurity content is two to three times higher, especially in terms of iron ion content, which can impact the external and internal quality of PVC products.

Molecular Weight:

The number-average and weight-average molecular weights of Calcium Carbide Method PVC are smaller than those of Ethylene Method PVC, and the molecular weight distribution is broader. As a result, the thermal stability, electrical insulation, mechanical properties, and weather resistance of Calcium Carbide Method PVC are inferior to those of Ethylene Method PVC.

Apparent Density:

Due to the smaller molecular weight, Calcium Carbide Method PVC has a higher bulk density and tighter cohesion, resulting in higher quality compared to Ethylene Method PVC.

Rheological/Plasticization Properties:

The relatively smaller molecular weight of Calcium Carbide Method PVC leads to a lower plasticization temperature, faster plasticization time, and smaller plasticization distance, providing an advantage for this method.

Mechanical Properties:

Ethylene Method PVC exhibits a fracture elongation rate 4% to 5% higher than Calcium Carbide Method PVC, tensile strength more than 10% higher, and impact strength over 20% higher. This significant difference in quality makes them suitable for different applications.

In general, Calcium Carbide Method PVC is commonly used in the production of drainage pipes, while Ethylene Method PVC is employed for manufacturing high-end PVC plastic products, such as transparent plastic items and plastics with stringent medical requirements. It's important to note that the choice between these methods depends on specific application requirements, cost considerations, and desired product characteristics.