What is Compound? The Difference Between Compound and Masterbatch
A compound is one of the most widely used raw materials in the downstream polymer and plastics industries, designed to produce a variety of plastic products with different properties.
What is a Compound?
Among the most important polymeric materials used in the production of plastic products is the compound. A compound is produced when two or more raw materials are mixed in specific proportions. In addition to the primary polymeric raw materials that form the base of the compound, various additives can also be added. Compounds are used as raw materials in the production of plastic products, helping to address issues such as the mixing of raw materials during production, raw material waste, and slow production speeds. In other words, compounds are made up of mixtures like polymers and additives that are created to facilitate and speed up the process of making plastic products. Some well-known types of compounds include polyethylene, polypropylene, PVC, calcium carbonate, polycarbonate, and more.
Why Do We Use Compounds?
In some equipment used in industries, such as injection molding machines or extruders, it is not possible to directly add masterbatch to the primary polymer. In such cases, manufacturers are forced to use compounds to ensure that the quality of the final product is not compromised. Moreover, from both an economic and hygiene perspective, using compounds is much more cost-effective for producing the final product than using masterbatch. This is because it eliminates the costs associated with cleaning and mixing masterbatch with the polymer base.
Types of Compounds
Polyethylene Compound
Polyethylene compounds are produced in different grades, distinguished by their density. To enhance certain physical properties of polyethylene, such as its strength and durability, pigments are added during the production process. When these two materials are combined, with specific volume and mass percentages, the resulting product is known as polyethylene compound.
The polyethylene enhanced by these pigments is used in the production of blown films, pressure pipes, and irrigation pipes. For water supply pipes, in addition to these pigments, a small amount of carbon black must also be added to the polyethylene to ensure optimal sealing of the pipes. The final product made from these combinations retains more stability under sunlight and is more cost-effective due to the increased lifespan of the final product.
Another positive feature of adding these pigments to the polymer base is the improvement in the material’s formability, allowing for the production of more varied shapes. The amount of compound added during the manufacturing process can vary based on the intended application. Typically, adding between 40% and 100% of these pigments to the base polymer is common. These pigments help the final product achieve more stability and reduce the likelihood of shape changes over time.
Polypropylene Compound
Polypropylene compounds (PP compounds) are widely used in the industry due to their high formability and excellent toughness. Polypropylene is a rigid, crystalline thermoplastic used in many household products, medical devices, and automobiles. Other practical characteristics of polypropylene compounds include low density, high elastic modulus, and good resistance to corrosion. This material is produced through extrusion methods, with the goal of improving the polymer’s properties by combining it with other materials to enhance its physical and mechanical properties. These compounds are available in various colors.
What is the Difference Between Compound and Masterbatch?
The use of compounds offers numerous advantages to manufacturers, facilitating and speeding up the production process. Some of the most important benefits of compounds include:
- Uniformity of Raw Materials: Ensures that the materials used in manufacturing are consistent.
- High Resistance to Sunlight: Enhanced durability under UV exposure.
- Competitive Price: Cost-effective for both domestic and international markets.
- Stable and Desired Quality: Maintains a consistent level of quality in the final product.
While masterbatch is primarily used to add specific characteristics like color or UV protection to raw polymer, compounds are designed to enhance the overall properties of the polymer itself and make the production process more efficient.