The world’s conventional polymers, derived from petroleum feedstocks, have outstanding benefits, such as durability, convenience and low costs.
But they are largely unsustainable. It has become a consensus: Plastics are having a materially distressing, foreboding impact on the environment.
Sustainable polymers (aka bioplastics) address those shortcomings while trying to maintain conventional polymers’ incredible, undeniable virtues. The challenge that’s increasingly acknowledged: How can those virtues be squared with plastics’ typical production and use, which so clearly create problems?
Plastics are inexpensive, lightweight and durable, making them a hugely advantageous industrial material (especially in retail, packaging and manufacturing contexts).
Yes, to have newer, sustainable plastics — carefully engineered from plant and other natural materials — match those traits, at the same cost, will be a tall order. But maybe, just maybe, it can be done.
It is precisely because plastics are so well-suited to humans’ consumptive needs that a staggering volume of both their feedstocks and post-consumer waste products now seriously bedraggle humanity. Most usual plastics durable enough to be very useful cause undue pollution in their creation and they do not reassimilate or recycle into the environment well at all.
So, the challenges facing the development of sustainable polymers include 1) matching or exceeding the physical properties and performance of traditional polymers (for example, toughness, melting point, color and elasticity); 2) ensuring that sustainable ones are truly better in abating pollution on either side of their dispatch to the enduser or market; and 3) if only to promote their adoption, keeping bioplastics comparable in price with petroleum-based ones.
Ongoing research at universities and companies worldwide address these challenges and otherwise tries to overcome any other limits of sustainable polymers, especially by refining or improving upon their physical traits and properties. But only insofar as doing so will yield feasible, cost-effective solutions.
The future for such technically tweaked bioplastics is not only auspicious. Considering the extent to which conventional plastics have insinuated themselves into current life, this future fast approaches and stands to grow thickly as a commercial market.
At least one part of the academic leading edge of the effort to supplant traditional plastics is the University of Minnesota’s Center for Sustainable Polymers (CSP), one of the U.S. National Science Foundation’s (NSF) nine national Centers for Chemical Innovation.
CSP researchers tackle the development of new, sustainable materials in a multitude of ways.
For example, studies of chemical routines that create sustainable polymers have led to new and better polymerisation catalysts (not coincidentally, one of the NSF’s other Centers for Chemical Innovation, as recently as 2018, was the Center for Enabling New Technologies Through Catalysis — CENTC — at the University of Pennsylvania in Philadelphia).
Currently, industrially created sustainable polymers are made from starch-containing plants like corn or sugarcane,and seed oils such as soybean oil. But investigators at the CSP and elsewhere are trying to make polymers from nonfood natural source materials, too, such as switchgrass, the lignin in trees, and corn stover.
A post on the CSP’s website confirms that new building blocks derived from plants for sustainable polymer synthesis are being developed and used to prepare complex polymer architectures conferring useful properties. In particular, CSP researchers are using multiblock polymers from natural starting materials in developing such endproducts as thermoplastic elastomers and pressure sensitive adhesives.
CSP researchers are also preparing new vegetable oil-derived polyols, including those derived from soybean oils, to produce key constituents of polyurethane (PU) foams (whether in regard to mechanical properties or processing methods, polyurethane is one of the most versatile of polymeric materials).
It’s as if foam is being reinvented in the process. Based on the choice of reactants, the PU can be a material that stays rigid, or an elastic substance that bends, or even a gel that both bends and flows a bit.
This extended array of achievable properties could make the new PUs instrumental in such applications as consumer products, medical devices, and transportation- and building-related uses.
The CSP has unabashedly adopted a multidisciplinary research approach to developing, improving, and expanding the applications of sustainable polymers. It’s pretty clear that such an approach is well-suited to the inherent challenges associated with developing these new materials.
But, perhaps more significantly, the center does not strictly limit itself to traditional research and development. Rather, it has partnered with industry leaders to understand their needs and to seek their guidance as to future research and application directions.
Indeed, the CSP has gone even one step further in its promotion of its work in building and applying bioplastics: It initiated collaborations with colleagues at the university’s Humphrey School of Public Affairs.
The point? To foster relationships with legislative leaders and allow scientists to participate with them in policy decisions that may impact, as never before, the future development and adoption of bioplastics.