Medium Molecular Weight Polyethylene (abbreviated as MMWPE) is a type of polyethylene, and its properties combine some characteristics of high molecular weight polyethylene and low molecular weight polyethylene. The main properties are introduced as follows:
Physical Properties
Appearance: Usually white or slightly yellow semi-transparent particles with a smooth surface, odorless and tasteless.
Density: The density is generally between 0.92 - 0.94g/cm³, lighter than water, and has good floating performance.
Melting Point: The melting point is relatively high, generally around 130 - 135℃, which enables it to maintain good stability within a certain temperature range.
Mechanical Properties
Strength: It has high tensile strength and tear resistance. The molecular chain length of MMWPE is moderate, and the intermolecular force is strong, allowing it to withstand large tensile forces and external forces without easily breaking, and the products have good durability.
Toughness: It has good toughness and impact resistance, capable of absorbing energy when subjected to impact and not easily cracking, suitable for manufacturing some components that need to withstand a certain impact force.
Wear Resistance: It has good wear resistance. The carbon-carbon bonds and carbon-hydrogen bonds in its molecular structure are relatively stable, not easily damaged during the friction process, and can maintain the integrity of the surface for a long time, reducing wear.
Chemical Properties
Corrosion Resistance: It has excellent chemical corrosion resistance, and has good tolerance to most acids, alkalis, salts and other chemical substances. It can maintain stable performance in different chemical environments, not easily corrode or undergo chemical reactions, and can be used to manufacture containers and pipelines for storing and transporting chemical drugs.
Water Resistance: It is insoluble in water and has low water absorption. In a humid environment or when in contact with water, its performance will not be significantly affected, and it can maintain good physical and mechanical properties for a long time.
Stability: It has stable chemical properties at room temperature, but under high temperature, high pressure or the action of specific catalysts, chemical reactions such as cross-linking and degradation may occur.
Processing Properties
Fluidity: Compared with high molecular weight polyethylene, the melt fluidity of MMWPE is better, which makes it easier to be formed during the processing process. Various processing methods such as extrusion, injection molding, blow molding, etc. can be adopted, and products of various shapes can be made to meet the needs of different application fields.
Processability: It is easy to process, and does not require too high pressure and temperature during the processing process. The processing cost is relatively low, and at the same time, it can improve production efficiency, making it suitable for large-scale industrial production.
Other Properties
Insulation Performance: It has good electrical insulation performance. There are no freely moving charge carriers in its molecular structure, so it can be used in the electrical field to manufacture insulation layers of wires and cables, insulated pipes, etc.
Self-lubricating Property: It has a certain self-lubricating property, and the surface friction coefficient is low, which gives it an advantage in some applications that require reducing friction. For example, when manufacturing components such as bearings and sliders, it can reduce the friction resistance and improve the operating efficiency and service life of the equipment.
