When to use a polypropylene liner instead of a polyethylene liner

The use of FIBC liners has increased dramatically. As the frequency of use of bulk bags in the food, pharmaceutical and chemical industries increases, there is a need to better understand which products and applications use which kind of inner liners.

To use lined FIBC bulk bags safely and effectively, it is important to know which liner to use. There are not enough standard polyethylene films under certain circumstances. In general, standard polyethylene liners are not sufficient when high temperature products are involved.

Some limits for Standard FIBC liners

For most of common applications, a standard polyethylene liner is sufficient. Polyethylene liners are very common in the food and pharmaceutical industries. Preventing contaminants from entering the product is the most important, but these liners have limitations. Most notably, it cannot withstand temperatures between 170 and 195 degrees Fahrenheit. The polyethylene material will begin to soften and dissolve. This can lead to unacceptable contamination of the product. In these cases, it is necessary to use liners made of completely different materials.

Polypropylene liners for bulk bag

Polypropylene liners are suitable for situations where a lining that can withstand temperatures above 170 degrees Fahrenheit is required. They are generally thicker and stronger than standard polyethylene liners. These are not very common because they are only used in very specific situations. However, they can withstand product temperatures up to 295 degrees Fahrenheit, higher than the unlined FIBC standard (200 degrees Fahrenheit) and higher than the polyethylene liner standard. (170 degrees Fahrenheit) is significant.