Baerlocher, a leading global supplier of plastics additives, announced at K 2019, that KNF FLEXPAK can now run 100 percent recycled film using post-industrial polyethylene (PE) film by improving its quality and consistency with Baerlocher’s BAEROPOL® T-Blend Resin Stabilizer. The Baerlocher technology resolved issues of variable film quality by preventing gels, bubble instability and haze that previously prevented KNF FLEXPAK, a U.S. custom packaging manufacturer, from incorporating post-industrial film in certain applications. In another successful trial, KNF FLEXPAK and Baerlocher partnered with EREMA, a leading manufacturer of plastic recycling equipment. EREMA successfully reprocessed film scrap stabilized with the BAEROPOL® T-Blend technology during testing at its facility in Ipswich, Mass.
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| Data from OIT experiments on various films, exhibiting high levels of stabilization from BAEROPOL T-1111 TX |
“Thanks to the consistently high quality of the post-industrial film incorporating BAEROPOL® T-Blend stabilizer, we can now run 100 percent recycled material with confidence in its quality and consistency,” says Ray Glenn, sales director, KNF FLEXPAK. “Previously, we would have had to blend it with expensive prime material. Now, our production rate for recycled material is pretty much equal to prime. Further, since film lines can now run more efficiently and recycled materials can be used in higher-end products, our business has become more sustainable and cost-effective.”
Stabilizing Post-industrial Film
KNF FLEXPAK sought to increase the use of scrap from its film production processes in other applications but encountered quality problems. The blown film process subjects resin to high-shear/high-temperature conditions that can lead to degradation. Recycling this film without adding stabilizers can cause crosslinking, creating gels and variable melt flow that affect quality and processing.
During trials, Baerlocher’s technical team identified BAEROPOL® T-1111 TX resin stabilizer as a prime candidate to help resolve these quality issues. BAEROPOL® T-Blends are blended synergistic polymer stabilizers that are pre-formulated to provide superior stabilization for most applications. They come in a variety of product forms (pastilles, rods, prills) and combine Baerlocher’s innovative Resin Stabilization Technology (RST) with various phenolic and phosphite stabilizers. According to Baerlocher, benefits imparted include:
• Color stability
• Melt stability
• Reduces/replaces phosphites
• Acid scavenger prevents degradation
• Made from renewable, sustainable resources
• Easy-to-handle, dust-free solution
• 100 percent active product
• Compatibility with Generally Recognized as Safe (GRAS) applications
• Food contact approval
Achieving Success with Recycled Film
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| Melt flow of the recycled material shows extremely low variance through the recycle process |
Testing according to ASTM D3895 – Standard Test Method for oxidative induction time (OIT) of Polyolefins by Differential Scanning Calorimetry (DSC) – showed that film produced with the T-Blend additive had significantly higher levels of stabilization than unstabilized film, contributing to the quality of the end product. Also, while recycled feedstock typically has high variation in melt flow, KNF FLEXPAK’s stabilized recycled resin shows remarkably stable melt flow values (± 1%).
After achieving excellent quality reprocessed film with BAEROPOL® T-1111 TX, the team took an extra step by turning to state-of-the-art equipment. EREMA recycled the film scrap using its INTAREMA® 1108 TVEplus® system, adding a dose of BAEROPOL® T-1111 TX stabilizer to further improve quality. Testing for OIT showed this recycled film remained sufficiently stabilized to preserve quality in its next application.
“As more manufacturers turn to post-industrial materials to achieve sustainability objectives for their customers and their own businesses, Baerlocher’s solutions make it easier to incorporate recycled content without sacrificing quality,” says Ian Query, technical specialist, Baerlocher USA.
