Reducing waste in packaging has become an important environmental focus for major corporations. Polypropylene (PP) is a preferred choice for plastics in packaging applications due to its low density, which reduces the amount of required material and the weight of shipments, lower greenhouse gas emissions during manufacture and full recyclability.

Milliken Chemical, a division of Milliken & Company, is playing an important role in the growing use of polypropylene as a replacement for less-sustainable plastics and other materials. Milliken’s Hyperform® hyper-nucleating agent overcomes variables in the waste stream to simplify PP recycling while Millad® clarifying additives enable PP to be substituted for clear materials such as polyethylene terephthalate (PET), polyvinyl chloride (PVC), polycarbonate (PC), polystyrene (PS), styrene acrylonitrile (SAN), acrylic and glass.

According to Brian Burkhart, global marketing manager for Millad clarifying agents, “Sustainability is a core value for Milliken and we have pursued environmental initiatives business-wide for decades. In addition to reducing waste and resource consumption in our own operations, we take pride in producing additives that can help other companies address the eco challenges of plastic packaging, which threaten to overwhelm landfills and litters the oceans and other natural areas. Our Millad and Hyperform additives simplify and expand the use of sustainable, recyclable polypropylene, helping to phase out materials with a heavier environmental footprint.”

Hyperform Nucleating Agent Levels the Playing Field for PP Recycling

Although many packaging manufacturers now seek to incorporate regrind and recycled materials to reduce costs and support sustainability, additives such as colorants and nucleators in mixed batches of polypropylene can cause processing issues including shrinkage and warpage. In turn, these variables can discourage use of recycled PP. Milliken’s Hyperform HPN-68L hyper-nucleating agent provides a solution to this problem by enhancing process stability and part quality, ultimately leveling different recycle streams.

Hyperform HPN-68L has the highest peak Tc (peak crystallization temperature) of any known nucleating agent. When added to recycled PP, Hyperform HPN-68L increases and levels the Tc of incoming recycle streams, allowing for faster and more consistent processing. Hyperform also promotes isotropic shrinkage, which is the key to reduced warpage and increased part quality.

Hyperform HPN-68L can be added at any point throughout the compounding process, making it an extremely flexible solution. It also accelerates throughput by avoiding the need to constantly recalibrate machine settings for different material properties. Overall, Hyperform provides a high return on investment by enabling the use of cost-effective regrind and recycled PP.