Polyethylene (PE) is the most preferred plastic type in the world. It is preferred in many areas from packaging to pipes, from toys to automotive parts. The reason it is so preferred is that it is a durable and versatile material.

However, although it is so common, many people do not have detailed information about the structure and properties of polyethylene. Therefore, as Lys Polychem, which operates in the field of plastic injection molding and production, we have brought together all the topics that are curious about PE filling.

What is Polyethylene?

Polyethylene stands out as a type of thermoplastic that is utilized in a wide variety of sectors by resisting extremely durable chemicals. Its common name in the plastics industry is PE, and the ethylene molecule is defined by the formula CH₂=CH₂; it contains two methylene groups joined by a double bond. Polyethylene, obtained as a result of the polymerization process of ethylene, is divided into low and high density categories depending on the density.  It is then shaped by molding, extrusion or casting methods.

 

Polyethylene, which hardly absorbs water, offers long-lasting applications thanks to its hardness, robustness and dimensional stability. Production techniques are generally classified into high pressure and low pressure operations; the high pressure method allows the formulation of LDPE and the low pressure method allows the formulation of HDPE and LLDPE types.

PE Filler Types

Polyethylene gains different properties according to its density. This directly affects the areas of use. There are basically two main types:

Ultra High Molecular Weight Polyethylene (UHMWPE)

UHMWPE, ultra-high molecular weight polyethylene, is also known as "super polymer". It stands out with its high strength, low friction and superior resistance to abrasion. Thanks to these properties, it can be used in many industrial applications.

It is generally preferred in the following areas:

• Building materials

• Automotive and aerospace

• Medical devices

• Battery disconnectors

UHMWPE is a reliable and efficient solution in any industry where high performance is expected.

High Density Polyethylene (HDPE)

HDPE, with a density in the range of 0.940-0.970 g/cm³, is crystalline or semi-crystalline thanks to its long unbranched carbon chains. It resists many chemicals with its water repellent structure. In addition, this resistance level increases with filling additives.

It stands out with its capacity to absorb impact energy and maintain its form at temperatures above 100 °C. Highly compatible with the forming process, PE filling also provides advantages in injection molding. Keeping the mold temperature between 50-70 °C improves the surface quality of the product. It can also be processed efficiently by methods such as extrusion, film drawing, powder coating and rotational molding. Thanks to its high electrical insulation properties, it is also widely used in electrical applications.

Low Density Polyethylene (LDPE)

Its density is between 0.910-0.940 g/cm³. Its production is carried out in the temperature range of 420-570 K and under 1000-3000 atm pressure. High purity ethylene gas is transferred to the reactor together with initiators and the polymerization process begins. The polyethylene obtained is extracted as a melt, pressed and granulated. The unreacted ethylene gas is recycled. The resulting polymer chains are composed of an average of 4,000 to 40,000 carbon atoms.

In these chains, there are about 20 branches for every 1000 carbon atoms. The amount of branching directly affects the crystallinity, density and physical properties of polyethylene. LDPE, which has approximately 50% crystallinity, shows a translucent structure. The increase in intermolecular spaces gives the material flexibility. Light, durable and economical, LDPE is widely used in the production of plastic bags, stretch film and bottles.

Polyethylene Properties

Polyethylene is preferred in many industrial applications due to its chemical stability, translucent appearance and balanced mechanical properties.

Main technical characteristics:

• Resistance to moisture

• Flexibility

• High chemical resistance

• Electrical insulation property

• Impact resistance and mechanical strength

All these properties are shaped depending on the production conditions that directly affect the usage areas and performance of polyethylene.

PE (Polyethylene) Areas of Use

Polyethylene is processed in different ways depending on its density. The high-density form is rigid, durable and has strong structural support. The low-density form is more flexible, lightweight and surface compatible. This difference is directly reflected in the areas of use.

High density polyethylene is used in the production of pipes and valves for water, sewage, ventilation and heating systems. Containers that transport substances such as fuel, chemicals and domestic waste are made from this raw material. Chemical-resistant floor coverings, fiber optic cable sheaths, power tools, automotive parts, toys, cutting boards, handles, rails and many household parts are also included in this class.

Low density polyethylene is preferred for packaging. Most soft products such as cling film, plastic bags, advertising bags, packaging film are made with PE. Many products such as containers, plastic boxes, bottles, kitchen utensils, slide strips, cosmetic containers, etc. benefit from the flexible nature of this material.

Lys Polychem PE Based Filler Compounds

Lys Polychem PE based filling compounds are innovative talc-free products that offer high performance and efficiency in the cable industry. Developed specifically for PVC cable production, these compounds can be used instead of traditional talc based filling materials, simplifying the production process and improving product quality.

Talc free filling technology effectively prevents adhesion between insulation and filling and between filling and sheathing layers in the cable structure. This provides the advantage of smooth processing on the production line and guarantees the long life and durability of the final product.

Thanks to its high speed working performance, it saves time in production lines and ensures maximum utilization of machine and equipment performance and speed. Thanks to its stable structure, it allows the product to be used up to the last kg of the product with the principle of 0 waste.

Thanks to its flexible polymeric structure, Lys Polychem PE filling compounds can operate with high efficiency even in non-tandem (single extrusion) systems. This saves manufacturers time, energy and costs.

The long shelf life of the products offers significant advantages in terms of stock management. They are also heat resistant, mechanically robust and resistant to chemical influences. These properties make Lys Polychem products not only a high quality cable filling material, but also a sustainable and economical solution.