Film Alternatives Project
Evaluating Performance and Environmental Impacts of Stretch Film Alternatives
Billions of pounds of stretch film are consumed annually, wrapping tens of billions of loads based on the original Lantech concept for stretch wrapping. Therefore, Lantech plays a critical role in understanding the environment impacts of stretch film.
Pressure on the environmental impacts of stretch film has reached a tipping point due to recent legislation focused on establishing a closed recycle loop by requiring Post-Consumer Recycled (PCR) content in stretch film. Numerous film alternatives have reactively entered the market. Brand owners, resin suppliers, and film companies are facing difficult and complex decisions ahead.
We initiated an investigation into stretch wrap alternatives. The evaluation compares performance, weight, cost, and estimated environmental impact across representative samples.
If you are interested in learning about this project, we invite you to download the white paper and watch the video that outlines our findings and conclusions.
Conclusions
- Lowest cost and carbon footprint – 100% virgin resin film
- Adding PCR to stretch film is currently not a sustainable alternative
- Stretch film should be recycled into other downstream products, but not back into stretch film
- Significant source reduction is possible with improvements in:
- Wrapper Technology
- Film Performance
- Machine Maintenance
FAQ
Post Consumer Recycled (PCR) stretch film is collected after it has been removed from loads at the ultimate destination. It then must be sorted, cleaned of labels, adhesive, ink and foreign matter, before being pelletized into resin for blending with virgin resin to produce PCR stretch film. It is distinguished from PIR (Post Industrial Recycled) stretch film which can be scrap or returned goods collected at the film producer.
The gels and non-compatible materials in PCR dramatically impact the ability to prestretch the film without excessive film breaks. Reducing prestretch to avoid film breaks generally has been shown to double the film weight to achieve the required containment force.
PCR stretch films from many sources were tested and found to have similar optimization settings. The sample of 30% PCR 80 Gauge, provided by Sigma Stretch Films USA, was selected as a representative.
Ultra-grade premium stretch films were selected to provide best case 100% virgin film. Samples from Malpack, Berry, Sigma, and Paragon were tested and found to have similar performance and optimization settings. A sample of Axis 60 gauge, provided by Malpack, Canada, was selected as a representative.
Optimizing normally requires experimenting with materials and all machine settings to find the prestretch and tension that provides the required containment force at the lowest film weight without film breaks. This is sometimes a tedious and time-consuming process which may have to be repeated if the film quality, load profiles or machine performance varies. When comparing wrapping materials it is critical to compare their performance only after each has been optimized.
Using the Lantech Film Auditor, 1000 feet film samples were run at the equivalent of 35 RPM, at progressively lower prestretch, until no holes were observed. The result of this test prescribed a prestretch of 150% for PCR and 275% for virgin film.
The containment force was measured with the ASTM listed CFT-6 tool on the stretchable materials, including the HexelStretch ™, PCR stretch film and the virgin resin stretch film. The less stretchable Mondi Advantage Paper was tensioned with a measured 40 pounds of force on the paper as it was wrapping.
The CO2 generated in production of a material is an accepted metric for carbon footprint and its relative environmental impact. We have adopted the CO2 content from production of PCR and virgin resin from Mondi’s well researched “Advantage Life Cycle Assessment” (2021)
Loads wrapped with 30% PCR required 270 total grams of resin to meet the required containment force, equaling 189 grams of virgin resin and 81 grams of PCR resin (left flask).
Virgin resin only required 132 grams to meet the same required containment force (133 grams less than the total grams required for PCR).
