Before plastic were found, scientists were developing a durable, light material using rubber latex from plants or shellac from beetle secretions.And in 1909, a chemist Leo Baekeland developed something synthetic, initial form of mass produced plastic called Bakelite.
Oil remains a key component to making plastics. But in the modern era, they become more and more problematic because of chemical properties such as dyes, fillers, and flame retardants included in their production. And the effect is, disastrous impact on the environment, humans, and other living things.
One can say, “But plastics are recyclable!” Truth be told, not all. Plastics have different longevity, but if they get recycled often, they won’t be as strong and not as favorable and they end up in landfills or burned. And speaking about burning, some plastics get straight up burned instead of being recycled.
So, when a reusable shopping bag made with recycled plastic gets threadbare with wear and tear, we can’t upcycle or recycle it to make a new product. And once the bag has reached its end of life, it’s either burned to make heat, electricity, or fuel, or ends up in a landfill as I mentioned. That’s the reality.
“Circular plastics and plastics upcycling are grand challenges. We’ve already seen the impact of plastic waste leaking into our aquatic ecosystems, and this trend is likely to be exacerbated by the increasing amounts of plastics being manufactured and the downstream pressure it places on our municipal recycling infrastructure,” said one of Berkeley Labs scientists, Brett Helms.
Fortunately, scientists at Berkeley Labs have developed a new strain of plastic that is just as good as our conventional, modern polymers, but they are also 100% recyclable indefinitely.
In a study published in April, the team of scientists described a new type of plastic that can be broken down at the molecular level. As a result, this type of plastic can be fully recovered and made into new items as great as the original.
“Most plastics were never made to be recycled but we have discovered a new way to assemble plastics that takes recycling into consideration from a molecular perspective,” said lead author Peter Christensen from Berkeley Lab’s Molecular Foundry
Basically, this new kind of plastic would always end up in recycling bin over and over again instead of landfills and eventually, the waters. The Berkeley team said that the new plastic could dramatically reduce the amount of plastic in landfills and even make the complicated business of recycling a lot easier, so facilities or companies would recycle more.
As mentioned before, modern plastics contain too much additives and that makes recycling process complicated, hence the burning or piling up in landfills. The process of recycling plastic is often gummed up by chemicals that stick to monomers, the small compounds that fuse to become polymers.
It’s not easy to scrub those polymers clean at the recycling facilities. Plastics with differing chemical compositions gather all together in the recycling center, making it impossible to predict what the recycled product will look like. Imagine having hard plastics, stretchy plastics, clear plastics, candy-colored plastics mixed altogether. It’s hard to know how usable the outcome will be isn’t it?
Most recycling companies prefer to collect certain types of used plastics in order to make things easier for them and also to not damage their machines, which is definitely not cheap.
Additionally, in some areas, the top grade type of recycled plastic pellets costs almost the same with “virgin” plastic. Buyers will most likely choose the fresher type instead of the used ones. It goes on and on like that and that’s one of the reasons why recycling companies/facilities are picky about processing plastics.
The infinitely recyclable plastic
PDK or polydiketoenamine, is the one that will change the future of plastic. The researchers first discovered how innovative PDK-based plastics are when Christensen was applying various acids to glassware used to make PDK adhesives. He noticed that the adhesive’s composition had changed.
Out if the drive to find out how the adhesive might have been transformed, Christensen analyzed the sample’s molecular structure with an NMR (nuclear magnetic resonance) spectroscopy instrument. And it turned out that they were the original monomers.
In order to be recyclable, plastics firstly needed to have an acid bath, scrubbing their monomers clean from all those clingy additives. The acid helps to break the bonds between the monomers and separate them from the chemical additives that give plastic its look and feel.
From there, those basic monomers form the building blocks of the next plastic product such as water bottles, adhesives, phone cases, watch bands, shoes, computer cables, and hard thermosets that are created by molding hot plastic material. Since the plastics get broken down into their most basic components, and built up again, there is no loss in quality or durability.
“With PDKs, the immutable bonds of conventional plastics are replaced with reversible bonds that allow the plastic to be recycled more effectively,” Helms said.
Imagine if this method gets conventionalised, recycling will be done a lot more often and thus facilities don’t need to be picky. Both the environment and humanity will be happy.
“This is an exciting time to start thinking about how to design both materials and recycling facilities to enable circular plastics,” said Helms.
Making PDK conventional
What needs to be done right now is launching this idea and findings to the world. This needs to be done very soon since plastic is getting more and more problematic each day.
“We’re interested in the chemistry that redirects plastic lifecycles from linear to circular,” said Helms. “We see an opportunity to make a difference for where there are no recycling options.”
Unfortunately, the researchers say this plastic won’t be released into the wild just yet. They’re working on adding natural materials to PDK, making sure that this new type of plastic won’t only be strong, flexible, and durable but also eco friendly (by incorporating plant-based materials and other sustainable sources).
While they’re focusing on these plastics, the researchers also have a plan to develop PDK plastics with a wide range of thermal and mechanical properties for applications as diverse as textiles, 3D printing, and foams.
“We’re at a critical point where we need to think about the infrastructure needed to modernize recycling facilities for future waste sorting and processing,” said Helms. “If these facilities were designed to recycle or upcycle PDK and related plastics, then we would be able to more effectively divert plastic from landfills and the oceans. This is an exciting time to start thinking about how to design both materials and recycling facilities to enable circular plastics.”
The researchers next plan to develop PDK plastics with a wide range of thermal and mechanical properties for applications as diverse as textiles, 3D printing, and foams. In addition, they are looking to expand the formulations by incorporating plant-based materials and other sustainable sources.
What do you think of PDK? Tell us your thoughts in the comments below.