These types of bags are very durable and are used to carry a wide range of materials. Polypropylene bags are the best choice for keeping your products fresh. They can greatly increase the shelf life when using products that are corrosive due to their anti-moisture properties. Polypropylene bags are used for dry goods as well as for exporting grain to other countries. Common uses for this type of bag include grain packaging, pet food, grains, animal feed, other food products, resins, fertilizers and chemicals.