What is MDPE plastic?

MDPE plastic, or Medium-Density Polyethylene, is a versatile thermoplastic known for its durability and flexibility. It is commonly used in applications such as water and gas pipelines, outdoor storage tanks, and playground equipment due to its resistance to cracking and environmental stress.

Examples of MDPE plastic

MDPE combines the flexibility of LDPE with the toughness of HDPE. Its color often indicates its purpose: yellow for gas, blue for wastewater and water supply due to its moisture and chemical resistance. Black MDPE handles above-ground water systems effectively, while also being robust and impact-resistant for mains water delivery.

MDPE is a top choice for ‘squeezy’ bottles, featuring shock and drop resistance, even surpassing HDPE in stress cracking resistance. It’s also used in liquid storage tanks like water butts and agricultural oil tanks.

Certainly, here are some examples of applications for MDPE plastic:

  1. Water and Gas Pipelines: MDPE is frequently used in the construction of water and gas distribution pipelines due to its resistance to cracking and its ability to safely transport these fluids.

  2. Outdoor Storage Tanks: MDPE is employed in the fabrication of outdoor storage tanks for various liquids, including chemicals and agricultural substances.

  3. Playground Equipment: Many playground structures, such as slides and climbing equipment, are constructed using MDPE plastic due to its durability and ability to withstand outdoor conditions.

  4. Geothermal Heat Exchangers: MDPE is used in geothermal systems for its heat resistance and long-term reliability.

  5. Ducts and Conduits: MDPE ducts and conduits are used for protecting electrical and telecommunication cables, providing insulation and protection against environmental factors.

  6. Drainage Systems: It is used in drainage systems and culverts for its resistance to corrosion and longevity.

These examples showcase the versatility and reliability of MDPE plastic in various industries and applications.

Recycling MDPE plastic

Similar to HDPE, MDPE is commonly accepted at recycling centers. Recycled MDPE finds new life in products like detergent bottles, recycling containers, picnic tables, outdoor items such as playhouses and storage bins, and even doghouses. MDPE, a blend of HDPE and LDPE, is categorized under the “2” resin identification code within the universal recycling symbol.


MDPE (Medium Density Polyethylene) and HDPE (High Density Polyethylene) are both members of the polyethylene family of plastics, but they have different properties and applications.

  1. Density: The primary difference between MDPE and HDPE is their density. HDPE has a higher density than MDPE, which results in it being stronger and more rigid.

  2. Strength and Rigidity: HDPE has better strength and rigidity compared to MDPE. This makes HDPE more suitable for applications where strength and durability are crucial, such as in the production of pipes, containers, and packaging materials.

  3. Chemical Resistance: Both MDPE and HDPE are known for their excellent chemical resistance, making them suitable for various chemical and solvent applications. However, HDPE generally has better chemical resistance than MDPE, making it more suitable for containers and pipes used in harsh chemical environments.

  4. Flexibility and Impact Resistance: MDPE, due to its lower density, tends to be more flexible and has better impact resistance than HDPE. This makes MDPE suitable for applications where some degree of flexibility is required, such as in the production of plastic bags, tubing, and packaging films.

  5. Applications: HDPE is commonly used in the production of pipes, packaging materials, bottles, and containers where strength and rigidity are crucial. MDPE, on the other hand, finds application in products that require a balance of strength and flexibility, such as plastic bags, gas pipes, and tubing for various industrial and commercial purposes.

Both MDPE and HDPE are widely used in various industries due to their versatility, durability, and resistance to chemicals and environmental stress cracking. The choice between MDPE and HDPE depends on the specific requirements of the application, including factors such as strength, flexibility, and chemical resistance.