Scientists Develop High Performance Nano-Cellulose Fibers to Strengthen Plastics

Brazilian scientists have developed a new way of manipulating cellulose that makes it far stronger and also makes it suitable for high performance applications. 

While it is often the subject of cellulosic biofuel research where it is broken down into its constituent sugars, cellulose is also of interest as a polymer in its own right. It is strong, light and has been used to produce biodegradable polymers. The properties of cellulose are rooted in its molecular structure and what these researchers did was produce a “nano-scale” structure with higher physical strength than “ordinary” cellulose structures. The new cellulose polymers are stronger, lighter and greener than many polymers used in industry. The new cellulose fibers can be used to reinforce other polymers, in some cases making them nearly as strong as Kevlar.The pure modified cellulose is expensive, however 1 kilo of modified cellulose can be used to reinforce 100 kilos of plastic, drastically improving its strength-to-weight ratio. For this cellulose application, the researchers found waste from a range of fruit bearing plants is an ideal feedstock. The manufacturing process involves heating the feedstock and adding a number of chemicals to reform the cellulose into the desired nano-structure.

Sao Paulo State University Study Leader, Alcides Leão;

"The properties of these plastics are incredible; they are light, but very strong about 30 per cent lighter and 3 to 4 times stronger. We believe that a lot of car parts, including dashboards, bumpers, side panels, will be made of nano-sized fruit fibers in the future. For one thing, they will help reduce the weight of cars and that will improve fuel economy."

Cellulose reinforced plastics have been tested by several car manufacturers and Leão predicts that it will find its way into new car models within the next few years.The potential weight reduction would be useful in reducing emissions across the transport sector and the cellulose-reinforced fibers are more resistant to damage from heat and chemicals. He even claims that one day it may be possible to replace metal automotive parts with parts produced from cellulose reinforced plastics.

This development is one of several which is beginning to broaden the markets in which biopolymers are suited for; for example, Entropy resins recently released its biobased epoxy which can be used in high performance composite products like snowboards and wind turbine blades. Biobased polymers are often lacking is in high performance applications, often limited to replacing petrochemical-based plastics in packaging. The fact that often bioplastics are biodegradable is useful for these applications, though it often results in lower resilience or weakening of the plastic over its working lifetime. Stronger polymers are generally less biodegradable so this nano-cellulose reinforcement will be less biodegradable, which consumers should be aware of. As this is commercialized it could open up a market for low carbon footprint, sustainable high performance materials that would compete with metals and specialist plastics, the green credentials of which are currently lacking.Potentially, this could be a major way for a broader range of manufacturers to decrease the carbon footprint of their products in future.