Have biomaterials reached a tipping point?

Scientists now understand how calcium carbonate, which creates the strength of sea shells, could be used in a variety of practical applciations.

The untapped potential for biotechnology to solve myriad sustainability challenges is drawing the attention of forward-thinking companies across industries. Today, over $400 billion worth of conventional manufacturing products are produced each year using biomass, according to (PDF) Duke University’s Center for Sustainability & Commerce.

While biofuels have garnered much of the spotlight, bio-based alternatives to plastic and other fossil-based materials quickly are making their way to the mainstream. These materials can be used for a variety of applications in manufacturing, construction, apparel and more. But many bio-based materials have yet to reach scale, thanks to industry clinging to classic chemistry.

This is beginning to change, as breakthroughs in bio-based materials engineering reach a tipping point. Collective understanding of how microbes work is, for the first time, allowing us to make chemicals in a safer and more environmentally friendly way. It is possible for us to engineer microbes to have specific functions, including a variety of sustainability applications.

"Although the technologies were developed many years ago, large scale production of polymers from biomass was not feasible because those technologies were too expensive," wrote researchers Lei Pei, Markus Schmidt and Wei Wei in a 2011 research paper. "However, in recent years, the innovations from the research sectors, particularly those on biotechnology, have made some of the biological conversions able to compete with the existing fossil-based processes."

Bioplastics punt petroleum

Bioplastics are just like conventional plastic, but they come from renewable resources rather than fossil fuels. They commonly include starch plastics, cellulosic polymers and polylactic acid (PLA), among many others. Bioplastics make up only 300,000 metric tons of the plastics market — less than 1 percent of the 181 million metric tons of synthetic plastics produced worldwide each year, according to Duke University. However, the bioplastics market is growing by 20 to 30 percent per year, which barely keeps up with demand.

The move to mainstreaming bioplastics made a huge leap forward in 2005 when Walmart announced it would sell some produce in PLA containers. Others, including Newman’s Own Organics and Wild Oats, have been using some PLA products for years.

The environmental advantages of bioplastics are self-evident: Their production produces less carbon dioxide than petrochemical-based plastics; and the uses of plant sources as renewable materials allow products to be recycled as new biomass sources for thermal, organic or chemical recycling.

DuPont's breakthroughs in biomaterials

Earlier this year, DuPont and Archer Daniels Midland Company announced a new breakthrough process in biomaterials engineering, using furan dicarboxylic methyl ester (FDME) from fructose as the primary biological input. FDME is listed by the U.S. Department of Energy as one of the 12 building blocks that can be converted into a number of high-value, bio-based chemicals or materials that can deliver high performance in several applications.

"This molecule is a game-changing platform technology," Simon Herriot, global business director for biomaterials at DuPont, claimed in statement announcing the breakthrough. "It will enable cost-efficient production of a variety of 100 percent renewable, high-performance chemicals and polymers with applications across a broad range of industries."

DuPont is using FDME in a polymer called polytrimethylene furandicarboxylate (PTF), a renewable and recyclable polyester that, when used to make bottles and other beverage packages, substantially improves gas-barrier properties compared to other polyesters. This means that PTF a good choice for customers in the beverage packaging industry looking to improve the shelf life of their products.

The strength of seashells

Around the same time DuPont made its announcement on FDME, researchers from the U.S. Department of Energy identified the chemical interactions that enable calcium carbonate crystals to form both hard-to-break shells and chalk that is soft enough to draw with on sidewalks.

Calcium carbonate is one of the most important materials on earth, crystallizing into chalk, shells and rocks, the researchers said. Animals from mollusks to people use calcium carbonate to make biominerals such as pearls, seashells, exoskeletons or the tiny organs in ears that maintain balance. These biominerals include proteins or other organic matter in the crystalline matrix to convert the weak calcium carbonate to hard, durable materials.

"This work helps us to sort out how rather weak crystals can form composite materials with remarkable mechanical properties," said materials scientist Jim De Yoreo of the Department of Energy's Pacific Northwest National Laboratory, in a statement. 

"It also provides us with ideas for trapping carbon dioxide in useful materials to deal with the excess greenhouse gases we're putting in the atmosphere, or for incorporating light-responsive nanoparticles into highly ordered crystalline matrices for solar energy applications."

Psychological barriers to biomaterials

The primary barrier to creating economies of scale for biomaterials seems to be rooted in psychology more than economics. We know that biomaterials can work just as well as traditional materials, and that the processes creating them can be cheaper and less environmentally deleterious. So, what are we waiting for?

For one thing, the popular narrative associates chemicals with being bad for human health and the environment, Lisa Dyson, CEO of bio-based materials firm Kiverdi, said during a presentation earlier this year. "Chemicals have been associated with being negative. But everything is made from chemicals, and bio-based chemicals aren’t bad."

Yet as consumers learn of the environmental benefits of bio-based materials, this misconception may change. And as businesses across industries learn of the economic benefits of employing renewable biological materials in their products and processes, the advent of biomaterials could be nigh.

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