top of page
Rolls of polyethylene liners for bulk bags in a manufacturing facility, showcasing Six Star Bulk Bag's high-quality FIBC liners. These liners provide additional protection and durability for bulk materials during transportation and storage.

Polyethylene (PE), Polypropylene, and Aluminum Foil

FIBC bulk bags offer exceptional solutions for safely and efficiently transporting and storing large quantities of products. Widely used across various industries such as agriculture, chemicals, pharmaceuticals, pet food, and metals and mining, these bags often require FIBC liners for enhanced functionality. The benefits of using FIBC liners include:

  • Oxygen Barrier

  • Moisture Barrier

  • Chemical Resistance

  • Anti-Static Properties

  • High Strength


These liners are particularly effective for food-grade products and fine powders. FIBC liners are designed to fit inside both duffle top and spout top bags, and can be equipped with attachment tabs to ensure they stay securely in place, eliminating the risk of liner discharge. The four most common types of poly liners are:

  • Lay-Flat Liners

  • Form-Fit Liners

  • Baffle Liners

  • Tubular Liners

  • Aluminum Liners


Lay-Flat Polyethylene Liners

Lay-flat polyethylene liners are the most commonly used type. They are cylindrical, open at the top, and typically heat-sealed at the bottom. If the bottom is heat-sealed, it must be cut to discharge the product. These liners can be pre-inserted into the bag or purchased by the roll.

Form-Fit Polyethylene Liners

Form-fit polyethylene liners are custom-designed to match the exact shape of the bag, including the spout inlet and outlet. These liners enhance the bag’s performance by protecting the product from contamination during processing, storage, and transport. They also facilitate consistent filling and discharge of products due to their lack of folds or pleats, and can either be permanently attached to the bag or easily removed after use.

Baffle Polyethylene Liners

The form-fit baffle design of these liners offers superior packaging performance and can reduce storage and shipping costs. Baffle liners are form-fitted to the FIBC and use internal baffles to maintain a square shape, preventing the bag from bulging. This square shape optimizes space on pallets and in trucks.

Additional benefits of baffle liners include:

  • Increased stack-ability

  • Enhanced stability

  • Up to 30% more product capacity in a given space

  • Protection from contamination

  • Formed spouts for easy filling and discharge


Tubular Liners

Tubular liners, similar to standard gusset liners, are made from polyethylene and are pre-inserted into the bag before leaving the manufacturing facility. Unlike gusset liners that have a sealed bottom, tubular liners have an open bottom that can be fed through the spout, eliminating the need for cutting during discharge. Tubular liners offer several advantages:

  • Application Suitability: Ideal for spout bottom bags, allowing efficient filling and discharging.

  • Cost Savings: Generally more cost-effective than form-fit liners.


Aluminum Foil Liners

Aluminum foil liners, or foil liners, improve filling, discharging, handling, and stability of FIBCs. These liners provide excellent protection against moisture, oxygen, and UV light, and are compatible with various bulk bags. Made from aluminum-laminated films, foil liners maintain the quality and integrity of the packed product. They can be customized with different aluminum compounds to meet specific application needs. Features of foil liners include:

  • Prevention of product damage and contamination

  • Available top and/or bottom spouts for safe filling and discharge

  • Protection against moisture and oxygen

  • Customizable materials for specific applications

The use of FIBC liners has significantly increased as bulk bags become more prevalent in the food, pharmaceutical, and chemical industries. This rise in usage has led to a greater need for information on selecting the appropriate liner for specific products and applications.

Limits of Standard FIBC Liners

For most products and applications, a standard polyethylene liner is more than sufficient. These liners are extremely common in the food and pharmaceutical industries where preventing contaminants from entering the product is crucial. However, polyethylene liners have their limits. They are unable to withstand temperatures exceeding 170°F, and at 195°F, the material begins to soften and melt, potentially contaminating the product. In these high-temperature scenarios, a different type of liner is necessary.

Polypropylene Liners

Polypropylene liners are designed for situations that require higher temperature resistance. These liners are generally thicker and sturdier than standard polyethylene liners, making them suitable for specific applications. Polypropylene liners can withstand product temperatures of up to 295°F, significantly higher than the 200°F limit of standard FIBCs without a liner and the 170°F limit of standard polyethylene liners.

Special Applications for Bitumen

Six Star Bulk Bag specializes in creating bulk bags designed for transporting and storing Bitumen. These bags are constructed to hold liquid and include specialized polypropylene liners capable of withstanding high temperatures, making them ideal for the transport and storage of Bitumen. Our professional approach ensures that the bags are not only robust but also provide maximum safety and efficiency for your operations. Additionally, our bags can maintain their standing shape even when Bitumen is poured in a liquid format, ensuring stability and ease of handling. This ability to hold their shape helps with storage efficiency, maximizing the use of available space and making them easier to stack and store.

Very High-Temperature Products Packaged and Transported in Bulk Bags

Very high-temperature products that are often packaged and transported in bulk bags include:

  • Bitumen/Asphalt: Used in road construction and roofing materials, bitumen needs to be transported at high temperatures to maintain its liquid state.

  • Molten Sulfur: Common in the chemical industry, molten sulfur is often transported at temperatures around 120°C (248°F) to keep it in a liquid state.

  • Hot Resins: Used in various manufacturing processes, resins are often transported at elevated temperatures to keep them in a workable state.

  • Hot Wax: Utilized in various industrial applications, hot wax needs to be maintained at high temperatures during transport to prevent solidification.

  • Certain Petrochemicals: Some petrochemical products require high-temperature transport to remain in a liquid state or to ensure proper chemical stability.

  • Molten Metal Powders: Used in specialized manufacturing processes, these powders may need to be transported at high temperatures to maintain their desired properties.

  • Hot Liquid Chemicals: Various chemical products that are stable at high temperatures but would solidify or become unusable at lower temperatures.


These products require bulk bags with specialized liners, such as polypropylene liners, which can withstand high temperatures without degrading, ensuring the safe and efficient transport of the materials.

In summary, selecting the appropriate liner for your FIBC is crucial for ensuring the safe and effective use of bulk bags, especially in high-temperature applications. Polypropylene liners are the preferred choice for such scenarios, offering superior heat resistance and durability.

Baffled liner, also known as a GAMBO liner, used for bulk bags to maintain shape and stability during storage and transport. This image showcases Six Star Bulk Bag's high-quality baffled liners designed for efficient and secure handling of bulk materials.
Baffled liner, also known as a GAMBO liner, used for bulk bags to maintain shape and stability during storage and transport. This image showcases Six Star Bulk Bag's high-quality baffled liners designed for efficient and secure handling of bulk materials.
Forklift handling Six Star Bulk Bags with a liner for secure storage and transport of bulk materials, demonstrating the strength and durability of Six Star Bulk Bag's packaging solutions.
bottom of page