When choosing materials for Circular FIBC Bags, the core considerations are polypropylene (PP) and polyethylene (PE). These two materials have different properties, requiring selection based on the material being loaded, the operating environment, and whether special treatment is needed.
Polypropylene (PP) is the most commonly used. It is wear-resistant, has high tensile strength, and can withstand temperatures below 50°C, making it suitable for storing non-corrosive materials such as grains and building material granules that can be stored at room temperature. PP material has a moderate cost and is recyclable, allowing for cost reduction through repeated use. However, it becomes brittle at low temperatures; for use in environments below 0°C, PP material with added cold-resistant agents should be selected.
Polyethylene (PE) material offers better flexibility and strong low-temperature resistance, maintaining its toughness even at -40°C. It is suitable for storing chemical liquids (requiring an inner liner) or materials stored in low-temperature environments. However, PE has lower wear resistance than PP, making it prone to breakage when loading sharp particles. It also has weaker high-temperature resistance, softening above 40°C, and should be protected from high-temperature exposure. If storing food-grade or pharmaceutical-grade materials, regardless of whether PP or PE is chosen, the material must meet food contact standards (such as FDA certification) to ensure no harmful substances are released.
Additionally, the thickness of the Circular FIBC Bag material must match the load-bearing capacity. For 1-3 tons of material, choose 80-100 g/m² PP/PE fabric; for over 3 tons, increase the thickness to 120-150 g/m². Insufficient thickness can easily lead to bag tearing.
