Material Highlight: 'Wood' You Believe Organic Cellulose Is a Viable Alternative To Plastic?
by Rudy Sanchez on 11/25/2020 | 4 Minute Read
When thinking about wood as a raw material, things like paper and cardboard come to mind. As it turns out, that only scratches the surface of the potential for the trusted substrate. Thanks to modern techniques, the uses for wood pulp isn’t limited to just paper but used to create alternatives to plastic.
The magic lies in the compound cellulose, an organic material that plants such as trees have in spades. It's the most plentiful of organic compounds on Earth, and the polysaccharide is the principal component of plant cell walls. It makes up some 33% of vegetable and plant fiber, and that's why someone might tell you that their asparagus tastes a little wooden. Cotton is the purest form of cellulose, and you can use it to make paper and even food additives, as cellulose powder gets used to thicken, emulsify, and stabilize processed foods. Cellulose is naturally biodegradable, and you can harvest it sustainably with proper tree management.
Not all cellulose-based plastics are necessarily biodegradable, and some are only industrially compostable, but researchers have found ways to design wood cellulose-based plastic alternatives free from such drawbacks. Scientists and engineers have a variety of techniques at their disposal to transform cellulose derived from trees and waste wood pulp.
When broken down into nanoparticles, cellulose-based materials can get formed into materials that are both water and air-resistant, but also in varying thickness and hardness so that they can withstand heat while being compostable. Applications for cellulose nanofibers include food bags, film, and even netted bags.
Another class of nano-cellulose is Crystalized Nano-Cellulose (CNC), and rather than fibers, the nano-particles’ form into a crystalline structure, which gives it strength on par with Kevlar, reinforces the impermeability of laminate materials. Due to its makeup, other materials can be suspended or embedded into the cellulose, such as electronics, deodorizers, and antibacterial compounds.
NatureFlex is a brand of certified compostable cellulose-based packaging, with a focus on food applications; it can also get used for stationery or other instances where one might apply a conventional plastic film. NatureFlex’s materials are designed to perform similarly to polyethylene terephthalate (PET) and oriented polypropylene (OPP) laminations. The firm’s materials are compostable, though they do note that some forms are only industrially compostable.
Another firm providing packaging solutions using cellulose-based materials is Austrian-based Verpackungszentrum (VPZ). Like NatureFlex, they provide solutions primarily for food, such as netting for produce like citrus and potatoes, which come with their own suitable outer packaging-they only need a sustainable way to get grouped into a sellable bundle. VPZ also makes sustainable wine labels using cellulose.
The potential of cellulose derived from wood pulp waste is not a new idea. In 2013, Nippon Paper Group established a lab to pursue cellulose nanofiber technology. Since 2017, the company has been able to produce, at a large scale, CNC material. Like NatureFlex and VPZ, Nippon Paper Group’s offering primarily serves the food market, as well as the cosmetics industry.
CelluForce is another firm offering materials taking advantage of cellulose nanotechnology. With a variety of solutions, the company's products can improve the performance of other organic materials such as polylactic acid (PLA), stabilize emulsions, and can get engineered to perform additional functions through chemical adjustments.
TIPA is another sustainable packaging solution available, but it isn't just food brands that get to have all the fun. Back in 2017, fashion designer Stella McCartney announced that her label would no longer use plastic film packaging and switched to TIPA's flexible compostables. Sure, you can use it to wrap your snack bars made from banana waste, but you can apply it easily to shipping mailers of all shapes and sizes.
However, not all cellulose-based plastics are created equal. These materials range from, “at least it’s not made from war-inspiring and Lambo-money oil” to “haaay man, check out my stinky organic compost pile.” Some you can only compost in an industrial facility, and to make it just a little more confusing, not every curbside collection will accept industrial compostable material. Plus, you can't mix these items with other recyclables, so they end up in a landfill anyway.
Trees have always been symbols of life, death, and rebirth. From ancient religions to comic books, trees have played a significant role in humanity’s existence. As we look to course-correct after our drunken dalliance with synthetic plastics, those wise and powerful plants that space murder bears worshiped have the potential to play a part in humanity’s penance, offering both designers and brands a viable alternative to wasteful materials.
Go to our partner A Plastic Planet's resource library, where you'll find plenty of cellulose suppliers.