Island Leaf Commodities is proud to offer an injection-grade, biodegradable polymer, as well as forks, knives, spoons, plates, trays, straws, and bowls made from it. Please shoot us an email at info@islandleaf.co for more information.
The Ubiquity of Polymers
Right now, as you read this, move your eyes away from the screen for a second. Take a look around, and try to internalize just how poignant the presence of plastics is in the world. Plastics surround us humans, and we have become reliant on them. Plastics make up parts of our smartphones; they seal the food we eat and keep it fresh; they constitute crucial car components such as fluid hoses, dashboards, and upholstery. Plastics also make up single-use packaging and containers.
Plastic use, which started about 70 years ago and picked up momentum at a break-neck speed over the past few decades, has devastated the Earth, mostly marine ecosystems. Many of these problems stem from the irresponsible and poor planned waste management infrastructure and the nature of polymers themselves. Fortunately, human ingenuity has conjured up a brilliant alternative to many single-use plastic items and a viable solution: 100% completely biodegradable polymers.
A Brief History of Plastics
Before we delve into how biodegradable plastics will serve as a potential savior for the planet, let's first explore what exactly plastics are and how they came into existence.
As many people know, scientists describe plastics as "polymers." Polymers are, however, an umbrella term used to describe many complex-molecular substances found in nature or synthesized in the lab. Indeed, the word polymer derives from two Greek roots: "poly-," meaning many, and "-mer," meaning parts. This word's universality has led scientists throughout the past few hundred years to apply it to molecules that compose very different things, from sugars to plastics.
The term "polymer" eventually became primarily associated to mean "plastics," mainly due to their all-encompassing role in day-to-day life. Compared to metals like steel and copper, plastics are relatively new, invented about a century and a half ago. However, the momentum of plastics' exponential growth and use since their inception is a rate virtually unmatched by any other material.
Plant-Based Plastics: The First Plastics
In the late 1860s, a company based in New York City wanted to produce billiard balls using any material other than ivory. The ongoing slaughter of thousands of elephants exclusively for their ivory tusks disturbed many American consumers. As motivation for inventors to find an elephant-friendly solution, the firm offered a $10,000 reward to anyone who could produce such a material.
By 1868, John Wesley Hyatt answered the call and successfully created a synthetic ivory substitute. Hyatt combined both cellulose from cotton fiber and camphor from tropical trees to make the first mass-produced and highly applicable plastic named "Celluloid." After receiving a patent for this Celluloid in 1869, Hyatt began mass-producing it at his own company. Celluloid's applications included not just billiard balls but also piano keys and false teeth. The rampant poor dental hygiene practices of the 19th century made the market for dentures and other false teeth quite lucrative, compelling Hyatt to name his firm the Albany Dental Plate Company. Albany Dental Plate company operated for a considerable amount of time, from 1870 to 1986.
The Petroleum Revolution
Ironically, the vast majority of plastics we use today are not plant-based like Hyatt's Celluloid, but petroleum-based. How and when did this fateful shift occur? During the same time that Hyatt's company was thriving, US businesses were also beginning to extract a natural resource that would become an essential ingredient for power production: oil. Oil's vast abundance sparked curiosity in several scientists.
By the mid-1930s, a scientist named Wallace Carothers used oil to derive a common plastic ubiquitous today: nylon. In the following years, the demand for nylon exploded with the advent of the second world war.
The military's insatiable need for materials during the second world war spurred plastics demand. US manufacturers like DuPont substituted domestically produced nylon for silk sourced from far away to make parachute cords. Scientists also invented saran wrap, still widely used today, to keep soldiers' food fresh for more extended periods. In the early years of US involvement in the war, Harper's Magazine published an article that acknowledged how the war fomented the production and widespread use of plastics.
Following nylon, scientists invented several other types of plastics, all stemming from petroleum. Plastics' application accelerated at elevated rates in the decades following the second world war. Automotive manufacturers started using plastics for multiple cars, including bumpers, side panels, and interior upholstery. Food and beverage manufacturers gradually implemented plastic packaging, phasing out fragile glass bottles and containers. Though perishable stayed fresher for longer periods and plastic packaging costs saved producers considerable sums of money, widespread plastic applications gave rise to significant problems.
Recycling
According to a recent report, four plastic types, PET, HDPE, LDPE, and PP, make up 85% of all plastics used. Producers use most of these plastics to make packaging for food and beverage products—bottles for milk, juice, soda, water; trays for meats and vegetable; bags for frozen produce and seafood; containers for yogurts and snacks—and this is just a list for foods. Plastics applications extend to virtually every industry. All plastics are recyclable in theory. The reality of the recyclability of these products after use, however, is very complicated.
Most plastic-waste in developed countries is collected using curbside programs, in which a traditional garbage truck gathers a hodgepodge of plastic waste. This waste is then taken to a Materials Recovery Facility (MRF), where high-tech optical sorting machines divide the plastic by type. Then, baling machines compress each type into massive square bales weighing up to 500 kgs. Pelletizers purchase these bales, and through the recycling process, transform used bottles, containers, and films of all sorts into fresh new pellets. Producers buy these pellets to create new end products. Consumers prefer to purchase products made from recycled plastics, as by doing so, they are contributing to the reduction of plastic pollution.
Slipping Through the Value Chain: The Problem of Single-Use Plastics
Plastic is a valuable material that allows food to stay fresh, provides secure packing for goods, and makes high-quality clothing that lasts, just to name a small fraction of plastic applications. Recycling keeps plastic waste out of the environment and discourages oil extraction for polymer production. While pelletizers and processors demand milk and juice bottles (HDPE) and single-use clear water bottles (PET), many single-use products are generally not recycled and, unfortunately, end up in landfills. Because plastic waste requires hundreds of years to decompose and harms animal life, discarding it into landfills is a poor option. Worse yet, many plastic items end up in rivers and streams, which eventually flow into the world's oceans.
In the oceans, plastic pollution contributes to various plastic garbage patches, which are massive accumulations of plastic waste—some of which are the size of countries. There are five of these garbage patches, and they present an existential threat to ocean life, human health, and the planet's health.
While many plastic types make up these devastating garbage patches, single-use, "disposable" plastic products present a particularly insidious threat. These products include plastic knives, forks, spoons, plates, cups, trays, and infamous straws. New technology allows for the safe production of those mentioned above, difficult to recycle plastic products.
Biodegradable Solutions for Plastics
Inspired by Hyatt's plant-based Celluloid, Wallace Carothers discovered Polylactic Acid, or PLA, using sugar cane and corn fibers, about ten years before he synthesized nylon. Because of the high-costs of mass production, chemical behemoths like DuPont did not produce PLA at scale. In recent years, however, food packagers have chosen to use PLA to make trays for meat and vegetable packaging in grocery stores.
In the early 1990s, Japanese chemical engineers at Mitsubishi Chemical, a major conglomerate, produced a plastic-like compound similar to both Hyatt's and PLA. Using fibers derived from sugar cane, corn, and cassava, Mitsubishi created PBS, or plant-based starch. This polymer had an array of applications, as end-product makers could use it in both blowing and injection-molding applications.
Despite being non-petroleum based, PBS and PLA both come with a few drawbacks.
While marketed as bio-degradable, both PBS and PLA can only decompose when exposed to food waste; one can not throw PLA and PBS products into the soil. Because both of these polymer chains need a special environment with the right kind of microbes, the correct amount of heat, and enough sunlight, to decompose. Due to these properties, PLA and PBS are both considered industrially compostable and are therefore not even suited for home composters.
When it comes to applications, PLA has even more drawbacks. While PBS does indeed make a sturdy end-product, PLA can tolerate an environment of no more than 60°C, meaning it is impossible to use for cups containing hot drinks, soup spoons, and bowls.
Fortunately, Taiwanese-based scientists and chemical engineers have designed an injection grade polymer used for applications that are as environmentally friendly and as easy to dispose of as a banana peel. Using PBS and bamboo fiber, they created a unique, durable, and fully biodegradable pellet.
The Bamboo/PBS Bio Compound
Bamboo, an endemic plant in Taiwan, reaches full maturity after just three years of growth. While growing, bamboo absorbs carbon dioxide and releases large volumes of oxygen into the air; it also is a precious natural resource for the compounding of a new type of biodegradable plastic. To make the compound, mature bamboo plants are first harvested; they, using mulching machinery, workers shred the bamboo stalks into a fibrous material. This material goes into a dehydrator and is transformed into a white powder. Finally, the powder is combined with PBS pellets to form an injection-grade compound resin.
The bamboo/PBS compound's molecular properties are highly advantageous, making the compound ideal for injection applications such as disposable straws, knives, forks, spoons, plates, cups, and trays. Once someone finishes using one of the products, they can throw it into the soil, as if it were an apple core or orange peel. After 150 days, the product will biodegrade into the ground, leaving no trace.
While products made of bamboo/PBS compound are 100% biodegradable, they are also incredibly resilient. This resiliency is due in part to the structural integrity the bamboo fiber provides for the compound. Utensils made from this compound bend just like plastic ones do and can be washed and reused over and over again. And, products made from the bamboo/PBS compound can withstand temperatures of up to 100°C, meaning that they can contain hot drinks and warm food. As a bonus, bamboo/PBS products are microwave safe.
This bamboo/PBS biodegradable compound will change the plastic industry for the better. Widespread use of this compound will relieve ecosystems of the stress they face due to plastic pollution and allow plastic recyclers to focus more time recycling common, high-demand products.
If you're interested in learning more about this groundbreaking bamboo/PBS compound, send us an email at info@islandleaf.co. We believe that biodegradable polymers will make up a large portion of plastic resin applications in the years to come.
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