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Low Levels of +Restore™ Additive from Riverdale Global Improve Properties of PP and HDPE Post-Consumer Recyclate while Enhancing Flow and Part Consistency

ASTON, PENNSYLVANIA, U.S.A., January 16, 2020: Physical property tests carried out by Riverdale Global in cooperation with a molder of packaging containers has demonstrated that +Restore™ liquid additive is even more effective than was originally claimed for improving the performance of plastics regrind based on post-consumer waste.

The test results indicate that at relatively low usage levels, the +Restore liquid additive enables processors running 100% post-consumer PP or HDPE to obtain products with virgin-like properties. Below are some test results comparing 100% virgin polypropylene with 100% PP regrind containing 0.4% +Restore additive:

---Flexural Modulus. Regrind PP tested at 99% of virgin PP.

---Strain at Yield. Regrind PP tested at 89% of virgin PP.

---Strain at Break. Regrind PP actually tested higher than virgin, at 106%.

---Izod Impact Strength. For regrind PP modified with +Restore additive, this property tested at 16% less than that of virgin PP, versus unmodified regrind at 49% less.

“These test results and similarly encouraging data for HDPE show that plastics processors can use the +Restore additive to meet sustainability goals by actually upcycling post-consumer waste, eliminating most, and in some cases all, of the property losses typically incurred in recycling,” said Jared Arbeter, technical sales manager.

+Restore also improves part consistency in comparison with untreated recycled material, Mr. Arbeter noted. As measured by standard deviation in a range of physical property tests, for example, HDPE regrind with 3% white concentrate exhibited 50% or more decreases in part variation when it contained 0.4% of the +Restore additive.

Other benefits are provided by the +Restore additive, according to Mr. Arbeter: “Because the additive has an affinity for the base polymer, it acts as a lubricant, enhancing melt flow. In addition, the +Restore molecule has a functional group that readily reacts with pigments, fibers, or fillers in the resin, while a different segment of the same molecule is designed to couple with the polymer; as a result, it forms a strong bond between resin and filler without compromising flexibility.”

The +Restore additive can be used in all thermoplastic processes, alone or in a blend with Riverdale Global’s liquid colors. Typical usage rates are in the 0.1 to 0.5% range.


RIVERDALE GLOBAL, LLC specializes in liquid color management for the plastics industry through our sealed color delivery system, computerized color technology, and global service network. The company’s world headquarters is in Aston, Pennsylvania, U.S.A., with international offices based in the United Kingdom, Dubai, Singapore, and China. The Riverdale legacy dates back to the early 1900s as a supplier of dyes and industrial chemicals with a focus today on economy through process automation, sustainability and local service. Email: