What is Plastic Granulate?

Plastic granulate is a small and fluid form of thermoplastic raw materials ready for processing. Raw material producers supply these materials to the plastics processing industry, usually in the form of granules. Granules, like gravel or sand, are free flowing and therefore easily transportable and processable.

The granular form is available not only in industrial production lines but also in meltable granules for end-users in some special applications.

In general, plastic granules consist of small particles that can be shaped into various plastic products by different production techniques. They can also be called "plastic pellets" depending on the size of the particles and the type of production. These plastics in granule form are processed into final products by injection molding, extrusion and blow molding.

How are Plastic Granules Produced?

The basis of plastic granules are polymer resins, which are formed by the polymerization of monomers. Among the most common raw materials are polyethylene, polypropylene, polyvinyl chloride (PVC), polyethylene terephthalate (PET) and polystyrene. The selected monomer determines the polymerization conditions and the final properties of the granulate.

Following polymerization, a process called compounding can be applied. At this stage, fillers, additives or colorants are added to the polymer to give it the desired properties.

The resulting plastic is melted at high temperature and formed into thin strips by extrusion. These strips are cooled by air or water. They are then cut with rotary knives into pieces several millimeters long. These small pieces take the form of plastic granules.

How to Process Plastic Granules?

Plastic granules are processed by different methods depending on the product to be produced. The most common techniques are injection molding and extrusion. In both methods, granules are melted by heating them in machines called extruders.

In injection molding, the molten plastic is injected into the mold at high pressure. This method is preferred for producing complex and detailed parts. In extrusion, the melted plastic is passed through a nozzle and formed into continuous forms such as tubes, profiles or films.

Blow molding is a combination of injection and extrusion techniques. In this method, liquid plastic is blown into the mold and hollow structures are obtained. In addition, granules with a certain grain size can be processed into hollow bodies by rotational molding.

Which Products are Produced from Plastic Granules?

Plastic granules are used as basic raw materials in many industries. Thanks to its malleable structure and production flexibility, it enables the production of a wide variety of products:

• Packaging Products: Packaging products such as bottles, bags and films are produced in different forms and specifications with the easy-to-process structure of granules.

• Construction Materials: Pipes, window profiles, insulation materials and other building components are produced with plastic granules. The durability of plastic and its resistance to external factors is the reason why it is preferred in this field.

• Automotive Parts: Parts such as bumpers, dashboards and interior trim are widely used in automotive manufacturing thanks to the light weight and design flexibility of plastic granules.

• Medical Products: Products such as syringes, tubes, medical packaging are produced from plastic granules due to their sterilizable structure and meeting hygiene standards.

• Electronic Components: Cable jackets, device housings and various plastic parts are used in the electronics industry due to the insulating and durable properties of granules.

• Household Goods: Plastic granules are widely preferred especially in the mass production of kitchen utensils due to their low maintenance, long life and cost advantages.

• Rubber Granules: Rubber granules, produced from recycled tires, usually have grain sizes ranging from 1-3.3 mm. They are used to provide elasticity on surfaces such as artificial turf and running tracks.

What are the Types of Plastic Granules?

Plastic granules show different physical and chemical properties depending on the type of polymer they are made of. Here are some common types of plastic granules:

• Polyethylene (PE) granules:  They are widely used thermoplastic derived from ethylene. This type is preferred in packaging, agriculture and construction.

• Polypropylene (PP) granules:  Resistant to high temperatures and chemicals. Used in packaging, textiles, automotive parts and household goods.

• Polyvinyl chloride (PVC) granules: They are made from Vinyl chloride monomers. They are widely used in building materials such as pipes, window profiles, cable sheathing and floor coverings.

• Polystyrene (PS) granules: They can be transparent or opaque. This type is used in disposable products, packaging and toys because of its ease of molding.

• Recycled plastic granules  Obtained by reprocessing used plastics. It is preferred in sustainable production processes and contributes to reducing environmental impacts.

Frequently Asked Questions about Plastic Granules

What is the role of monomers and polymerization conditions in plastic compound production?

Monomers are decisive for the properties of plastic granules. The polymerization process creates polymer resins. Through the choice of monomers and controlled production conditions, the properties of plastic granules can be shaped.

To what extent are the properties of plastic granules influenced by the additives and aggregates used during compounding?

Additives and aggregates directly influence the properties of plastic granules. Properties such as mechanical strength, heat resistance, flexibility, flame retardancy and UV stability are optimized with these components.

What are the construction products made from plastic granules and what are their advantages?

Plastic granules are used in pipes, profiles and insulation materials. They offer advantages such as durability, weather resistance, light weight and design flexibility.

How are processing techniques such as injection molding, extrusion or blow molding affected by the grain size of the plastic granulate?

Grain size directly influences the processing process. Homogeneous and appropriately sized granules ensure uniform melting, flow and shaping in molding techniques.

What are the special challenges in terms of hygiene and sterilization when processing plastic compounds in the medical sector?

Plastic granules used in medical products must be processed under sterile and hygienic conditions. Compliance with sterilization, biocompatibility and the risk of contamination in the production process are critical.

What are the contributions of plastic granulate to sustainable product production?

Advanced recycling technologies enable plastic waste to be recycled into granules. This process contributes to sustainable material production. Through efficient collection, sorting and materials engineering, the recycled granules can be reused in new products.