A blog posting here a few weeks ago covered three general “themes” of the debate on the use of vinyl/PVC. After the posting, commentators emphasized that a key issue with flexible vinyl compounds has to do with the phthalate-based plasticizers that are used to make the material soft and pliable.
In particular, it’s really some of the migrating “low” phthalate plasticizers that are under most scrutiny, with most gradually being phased out of use in Europe and elsewhere. Making clear distinctions between the different kinds of phthalates, the European Council for Plasticisers and Intermediates (ECPI) offers a clear listing and explanation of the various types and names, plus a report (PDF) showing trends in their use.
And there are also non-phthalate “specialty plasticizers,” and the ECPI offers a good run-down of those as well. Each has certain uses, though sometimes only as a secondary plasticizer in addition to a standard plasticizer -- and each has drawbacks, such as high costs or processing challenges.
Similar to the way in which the words “vinyl” and “PVC” sound like poison now to “green” consumers, the word “phthalate” now shows up as a red flag for regulators. So more producers are releasing new non-phthalate/bio-based plasticizers; below are just a few recent product announcements (though please note that this selection is not an endorsement of particular products or companies):
- The Ecolibrium bio-based plasticizer from Dow Chemical Co. is reportedly being used in compounds from partner Teknor Apex Co. for PVC applications such as wire and cable, footwear, and flooring; the bioplasticizer is said to be completely derived from “a vegetable-derived, natural-based oil.”
- PolyOne and Archer Daniels Midland have collaborated on creating the next generation “reFlex” bioplasticizer to be highlighted at NPE2012 in April; the material reportedly shows better thermal stability, lower migration, and better plasticization efficiency compared with butyl benzyl phthalate (BBP), targeting phthalate-free toys, consumer goods, and building and construction applications.
- Emerald Kalama Chemical has announced the construction of another plant for producing its K-Flex glycol dibenzoate ester plasticizer, said to be a REACH-preregistered, low-VOC material for vinyl flooring and other applications.
- Two other non-phthalate options announced last year include Ferro Corporation’s Santicizer Platinum P-1000, which is said to show low volatility, migration, and extractability in water and solvents, plus resistance to mold and bacterial growth; and International Specialty Products Inc.’s Flexidone plasticizer, based on alkyl pyrrolidone chemistry, providing properties in PVC that reportedly are similar to those with conventional plasticizers.
- And OXEA provides OXSOFT phthalate-free plasticizers for a variety of applications; the company also publishes an objective and concise blog on the subject, helpfully highlighting factors and trends behind the use of phthalates and non-phthalates.
Non-phthalate plasticizers may not prevent companies like Procter and Gamble from eliminating vinyl packaging. And of course they can’t address the chlorine in PVC’s basic structure, which is at the core of many environmentalists’ complaints about vinyl. But as more of them become capable of fulfilling the duties of phased-out phthalates (and decrease in price too), more of them will come into use. Still, regulators will be wanting documentation about the possible health effects of these new materials to compare with those of the old.
Mike Tolinski is the author of Plastics and Sustainability, published in Oct. 2011 by Wiley-Scrivener, and he is Contributing Editor for Plastics Engineering magazine of the Society of Plastics Engineers in the USA. His views have been shaped by his engineering, university, and journalism experience in the plastics and manufacturing industries over the past 21 years.