The world fell in love with plastics because they’re cheap, convenient, lightweight and long-lasting. For these same reasons, plastics are now trashing the Earth.
Colorado State University chemists have announced in the journal Science another major step toward waste-free, sustainable materials that could one day compete with conventional plastics. Led by Eugene Chen, professor in the Department of Chemistry, they have discovered a polymer with many of the same characteristics we enjoy in plastics, such as light weight, heat resistance, strength and durability. But the new polymer, unlike typical petroleum plastics, can be converted back to its original small-molecule state for complete chemical recyclability. This can be accomplished without the use of toxic chemicals or intensive lab procedures.
Polymers are a broad class of materials characterized by long chains of chemically bonded, repeating molecular units called monomers. Synthetic polymers today include plastics, as well as fibers, ceramics, rubbers, coatings, and many other commercial products.
Building on fundamental knowledge
The work builds on a previous generation of a chemically recyclable polymer Chen’s lab first demonstrated in 2015. Making the old version required extremely cold conditions that would have limited its industrial potential. The previous polymer also had low heat resistance and molecular weight, and, while plastic-like, was relatively soft.
But the fundamental knowledge gained from that study was invaluable, Chen said. It led to a design principle for developing future-generation polymers that not only are chemically recyclable, but also exhibit robust practical properties.
The new, much-improved polymer structure resolves the issues of the first-generation material. The monomer can be conveniently polymerized under environmentally friendly, industrially realistic conditions: solvent-free, at room temperature, with just a few minutes of reaction time and only a trace amount of catalyst. The resulting material has a high molecular weight, thermal stability and crystallinity, and mechanical properties that perform very much like a plastic. Most importantly, the polymer can be recycled back to its original, monomeric state under mild lab conditions, using a catalyst. Without need for further purification, the monomer can be re-polymerized, thus establishing what Chen calls a circular materials life cycle.
This piece of innovative chemistry has Chen and his colleagues excited for a future in which new, green plastics, rather than surviving in landfills and oceans for millions of years, can be simply placed in a reactor and, in chemical parlance, de-polymerized to recover their value – not possible for today’s petroleum plastics. Back at its chemical starting point, the material could be used over and over again – completely redefining what it means to “recycle.”
“The polymers can be chemically recycled and reused, in principle, infinitely,” Chen said.
Chen stresses that the new polymer technology has only been demonstrated at the academic lab scale. There is still much work to be done to perfect the patent-pending monomer and polymer production processes he and colleagues have invented.
With the help of a seed grant from CSU Ventures, the chemists are optimizing their monomer synthesis process and developing new, even more cost-effective routes to such polymers. They’re also working on scalability issues on their monomer-polymer-monomer recycling setup, while further researching new chemical structures for even better recyclable materials.
“It would be our dream to see this chemically recyclable polymer technology materialize in the marketplace,” Chen said.
The paper’s first author is CSU research scientist Jian-Bo Zhu. Co-authors are graduate students Eli Watson and Jing Tang.
Chen’s co-authors, from left: Research scientist Jian-Bo Zhu, and graduate students Jing Tang and Eli Watson.
The Latest on: Recyclable plastic
via Google News
The Latest on: Recyclable plastic
- Charlotte company no longer recycling plastic due to global crisis on December 19, 2018 at 11:51 pm
CHARLOTTE, N.C. — There's a global crisis over what to do with millions of tons of discarded plastic, and other trash is now affecting the Carolinas. Signature Waste, one of the Charlotte area’s major ... […]
- Nestle Waters North America Will Achieve 25 Percent Recycled Plastic in its Packaging by 2021 on December 19, 2018 at 11:33 pm
STAMFORD, Conn: Nestle Waters North America , one of the leading beverage companies in North America, announced that it will achieve 25 percent recycled plastic across its U.S. domestic portfolio by 2... […]
- Union Residents Asked Participate in Plastic Bag Challenge on December 19, 2018 at 10:00 pm
UNION, NJ – Union residents are being encouraged to collect various types of plastic bags for a recycling challenge through TREX Outdoor Furniture. The TREX Plastic Bag Challenge is currently underway ... […]
- Recycled Plastic & Plastic Waste to Oil Market – Competitive Insights 2025 on December 19, 2018 at 8:22 pm
The tremendously rising use of plastic has resulted in the generation of a massive amount of plastic waste across the globe. The level of plastic waste generation has grown significantly in developed ... […]
- Global recycling shift phases out glass on December 19, 2018 at 6:43 pm
"Glass collected through single-stream recycling collection is heavily contaminated once sorted from other commodity types. Broken glass also contaminates other fiber and plastic, in turn, effecting t... […]
- Boston joins plastic bag ban-wagon on December 19, 2018 at 6:33 pm
Composting isn’t a good answer for bio-based plastic items because of the length of time—three to six months—it takes for that material to decompose. Even then, it is only a partial decomposition. Rec... […]
- EU moves toward ban of single-use plastics on December 19, 2018 at 5:19 pm
The EU’s executive branch, the European Commission, estimates that almost 60 percent of the over 28 million tons of plastic waste produced in the bloc each year comes from packaging, with much of it e... […]
- Postconsumer Plastic Bottle Recycling: Association of Plastic Recyclers/American Chemistry Council Issue 2017 Report on December 19, 2018 at 4:57 pm
The document constitutes the 28th annual National Postconsumer Plastic Bottle Recycling Report. Key figures cited in the Report include: Plastic bottle recycling declined slightly in 2017 3.6 percent ... […]
- This Is, Indeed, the Statistic of 2018: 90.5 Percent of Plastic Is Not Recycled on December 19, 2018 at 2:20 pm
What is progress? Before answering this question, let's appreciate a statistic that Britain’s Royal Statistical Society has correctly decided is international statistic of the year: "90.5 percent of p... […]
via Bing News