Page 32 - Plastics News November 2021

FEATURE

the value of additional stabilization. and Food Branch (HPFB) in Canada property retention, and aesthetics.
Crosslinking, which is a common result will review the recycling process and For cleanliness and gel level, ask your
of insufficiently stabilized resin, will material source(s), and then issue letters supplier about its cleaning steps and
bring the MI down and make processing of non-objection (LNO or LONO), melt-filtration capabilities. For physical
more difficult. Having additional AO which are opinions on the recycling property retention, matching density is
added during production by your PCR process used to produce material for important, as previously noted. If this
supplier is ideal to protect the resin food-contact applications and will is not possible, consider what can be
through at least its third heat history to include food type or use restrictions done to offset the resulting change in
ensure minimal degradation occurs and for the resulting PCR. However, the performance. With regards to aesthetics,
the MI is preserved. LNO is just one criterion that must our advice is to embrace the ugly!
be met in order to comply with food-
Are There Tactics to Reduce Odors contact requirements. To be considered PCR can look very good but is not
Commonly Associated with PCR? suitable for the final application from likely to look the same as virgin resin,
Most plastic converters report that a regulatory perspective, the PCR even if the utmost care is taken in its
PCR has more odor than virgin plastic. will typically go through additional production. Let the different aesthetic
Good PCR suppliers address odor testing and obtain additional regulatory start telling the story for the consumer
early in the recycling process. It is statements.For cleanliness and gel level, to understand that PCR is being used in
critical to remove paper labels and ask your supplier about its cleaning steps your product design – the sustainability
cellulosic/organic contamination in and melt-filtration capabilities. The EU messaging is a key component to driving
the wash step to prevent particles from has a similar approach, but also requires growth in the circular economy! We
charring during the extrusion process. only food-contact material be recycled have seen levels of PCR in excess of
De-volatilization is an additional step for use in food-contact applications. 70% for some can liners and around
that occurs at some recyclers to drive Similarly to the FDA and HPFB, 40% for shrink film. For more sensitive
off volatile organic compounds and The European Food Safety Authority applications with stringent requirements,
can result in a noticeable reduction in (EFSA) will review a recycling process to starting at a lower dosage such as 10%
odor. Deodorizing additives can also be assess its suitability in producing food- and building confidence and experience
used to improve perceived odors. Ask contact PCR. To date, however, opinions before targeting higher loadings is a
your supplier if any of these steps are have only been issued for rPET. It is good strategy. Higher loadings will be
included in their process. anticipated that this may change with limited by required part performance
and/or aesthetics. Burying the PCR in a
the recent push in the EU to develop
How Do You Know Whether Recy- core layer in a multi-layer structure can
cled Resin Will Meet Special Crite- a comprehensive strategy to include help overcome PCR aesthetics to some
ria for Your Application? plastic in a circular economy. extent, and relying on high-performance
If you have a special criterion such as How Do You Determine the Maxi- blend components can offset a reduction
absence declarations, California Prop mum PCR Content You Can Use in in physical performance.
65, Toxins in Packaging Clearinghouse Your Product or Pack-
(TPCH) or food-contact statements, age Design?
you must work with your supplier to Exploring how much
address these needs. Food-contact PCR PCR can be incorporated
is in particularly high demand as brand into your product design
owners work to achieve packaging is a key component of
sustainability goals. Globally, there are application development
differences in how the use of PCR is and should be determined
regulated for food-contact applications. on a case-by-case basis
In the U.S. and Canada, the PCR through trial evaluations
material must meet all the same legal and modeling. The
requirements as virgin material. The ultimate PCR content can
Food and Drug Administration (FDA) depend on the level of gels
in the U.S. and the Health Products or impurities, physical-

32 PLASTICS NEWS NOVEMBER 2021