Polyester and polypropylene may sound similar, but they are two vastly different strapping materials with their own benefits, drawbacks, and use cases.
Material Origins And Manufacturing of Polyester and Polypropylene Strapping
Polypropylene (or poly strapping) is made from polypropylene resin, a thermoplastic polymer derived from petroleum. It is then melted, extruded, cooled, stretched out, embossed, and finally wound like a cord. Polyester has a similar process, although rather than using resin that needs melting, polyester uses polyethylene terephthalate as a basis before being extruded and wound. The most considerable difference between the materials used is that polypropylene resin is saturated, whereas polyester is unsaturated and uses a different, more complex series of manufacturing steps.
How Do Polyester Strapping and Polypropylene Strapping Compare
- Tensile strength: Polyester is far more potent than poly materials and has higher tensile strength, making it better for heavier packaging while offering greater rigidity. After application, polypropylene loses much of its tensile strength and can’t be trusted for heavy loads.
- Elasticity And Recovery: Polypropylene has a weak elasticity and will often lose upwards of half of the applied tension within an hour of use. Conversely, polyester keeps its rigidity like steel, maintaining its shape far better after tension. However, polyester will not recover after stretching, whereas polypropylene can recover about 25% of its shape.
- UV Resistance: Polypropylene will commonly break down quickly in high UV radiation, whereas polyester is manufactured with innate UV resistance.
- Cost: Depending on your specific needs, polypropylene and polyester can affect costs differently. Polypropylene is naturally cheaper, but it is not as reusable as polyester and, therefore, is best used for single use or in light batches of products. Polyester, however, is significantly more expensive and should be used for mid or high-weight packaging solutions and multiple uses.
- Environmental Impact: Both materials can be made from 100% recycled materials, lessening the amount of petroleum needed for production. However, due to the nature of polypropylene to break down when exposed to UV, it is a less reliable recycled product.
- Safety: Polyester tends to fray over time and should be replaced at the first sign of fraying. When handling polypropylene, it is essential to remember that the embossing is there to help with strength, and if that coating ever rubs off, it can snap without warning. Both products are relatively safe, although polyester is more reliable due to its rigidity and strength.
- Industries That Benefit From Polypropylene Strapping:
- Printed Material Shipping (Newspapers, Magazines)
- Direct mail and small packages
- Millwork
- Flooring materials and small bits
- Small Appliances
- Clothing and other light textiles
- Foods
- Industries That Benefit From Polyester Strapping
- Metals
- Construction Materials:
- Lumber
- Bricks
- Tiles
- Pallets of Bottles and Cans For Shipping Or Recycling
- Excellent for stabilizing and palletizing heavy loads
- Expert Recommendation For When To Use Polypropylene Or Polyester: Polypropylene is best used for lightweight products and large but relatively stable objects. Its low cost makes it a fantastic product for the end of the supply chain and temporary storage, where products are moved quickly and without much need for strength. Polyester is more suited for any application you may use steel banding. Its strength is perfect for heavyweight applications and products that must be secured for long-term and long-distance shipping.
Contact USA Strapping For All Your Strapping And Shipping Needs
We have everything you need to maintain your polyester or polypropylene strapping inventory. Get it all in one place, from tools to products, and know that everything will cost you less and come with the highest quality. Reach out to one of our USA Strapping team members today by phone at 888-768-0001.