Table of Contents
Definition
- High-density polyethylene (HDPE) is a type of thermoplastic polymer made from ethylene monomers. It has a high density compared to other forms of polyethylene, which gives it increased strength, stiffness, and impact resistance. HDPE is widely used in various applications due to its excellent chemical resistance, low moisture absorption, and good electrical insulation properties.
Polymerization of HDPE:
- The polymerization method of high-density polyethylene by the Zieglar Natta process.
- High-density polyethylene is formed by the addition of radical polymerization of ethene monomers. HDPE had a high density and a high softening point.
- HDPE is a thermoplastic polymer.
- HDPE is commonly recycled, and it has a recycled range “2”.
- HDPE incorporates a linear structure and no or low degree of branching.
[-CH₂-CH₂-] n
- HDPE-made products are long-lasting and easy to maintain. For food packaging, food stored in HDPE containers, bottles, and pouches does not get contaminated by the polymer.
HDPE Properties–
- The density of HDPE is 0.93 to 0.97 g/cm³.
- High-density polyethylene has a linear structure.
- It has a high intermolecular force (high intermolecular bonding) due to its linear structure.
- The high-density polyethylene processing temperature is 175 °C to 180 °C. And hdpe starts melting at 130 °C to 135 °C.
- Due to high intermolecular bonding, its tensile strength is also very high.
- HDPE can withstand heavier loads than most of the other types of polyethylene.
- HDPE has high intermolecular bonding (c-c), so it has very low water absorption.
- HDPE has excellent electrical insulating properties.
- HDPE has a hydrophobic surface, so it is resistant to most solvents and has medium resistance to oil and greases.
- Ultraviolet rays make a reaction with the HDPE surface, so it has poor ultraviolet and low heat resistance.
- It is a highly dense material, so high-frequency welding and joining are impossible.
Application-
Packaging:
HDPE is used to manufacture bottles, containers, and packaging films for food, beverages, chemicals, and pharmaceuticals.
Pipes and fittings:
It is widely used for the transportation of water, gas, and other fluids due to its excellent chemical resistance and low friction coefficient.
Construction:
HDPE pipes are used for underground drainage systems, sewer lines, and cable protection. It is also used for geomembranes, geotextiles, and plastic lumber.
Industrial applications:
Automotive:
It is used in fuel tanks, bumpers, and various components due to its impact resistance and lightweight nature.
Agriculture:
HDPE is used for irrigation pipes, greenhouse films, and agricultural containers due to its durability and resistance to chemicals and UV radiation.
Recycled products:
- HDPE can be recycled and used in the production of recycled plastic products such as plastic lumber, crates, and containers.
Trade name of High-Density Polyethylene
HD53EA010–
- It is a high-density polyethylene-reliance plastic material.
- It is used for stretched tap products and different extrusion products with a good combination of tenacity and elongation.
- It has high bubble stability in blown film extrusion.
- It has high clarity and good barrier properties.
- HD53EA010 is a low-haziness and low-cloudy material.
Density | 0.941-0.955 g/cc |
Melt flow index (MFI) | 1.0 g/10 min |
Tensile strength at break | 18.5-23.5 MPa |
Dart Impact Strength | No break |
Elongation at break | 100-1000 % |
Hardness | D 60 – 70 |
Melting point | 130 – 135 °C |
F46003–
- F46003 is also high-density polyethylene industrial grade.
- It is mostly used in blown film extrusion and it also used in extrusion blow Moulding, extrusion pipe, extrusion sheet, etc.
- F46003 has good stiffness due to high intermolecular force.
- Its structure is linear, so it increases melting strength and impact resistance.
Density | 0.945-0.948 g/cc |
Melt flow index (MFI) | 0.40 g/10 min |
Tensile strength at yield (MD/TD) | 30 / 25 MPa |
Dart Impact Strength | 2 g/mic. |
Elongation at break (MD/TD) | 780 / 950 % |
Hardness | D 60 – 70 |
Melting point | 130 – 135 °C |
FAQ Of HDPE
What is High-Density Polyethylene (HDPE)?
HDPE is a thermoplastic polymer made from petroleum. It is known for its high strength-to-density ratio, making it a versatile material for a wide range of applications.
What are the key properties of HDPE?
High Strength-to-Density Ratio: HDPE is strong yet lightweight.
Chemical Resistance: resistant to most acids, alkalis, and solvents.
Moisture Resistance: Impermeable to water, making it ideal for containers and pipes.
Impact Resistance: Can
withstand physical impacts without breaking.
Thermal Resistance: Can handle temperatures up to 120°C (248°F) for short periods.
UV Resistance: Can be treated to resist UV degradation.
Recyclability: HDPE is 100% recyclable and is labeled as plastic #2.
Is HDPE biodegradable?
No, HDPE is not biodegradable. However, it is recyclable, which helps reduce its environmental impact.
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