Larry C. Dickinson is CEO of 3F, a bio-composite startup, in Raleigh, N.C., which is developing kenaf-fiber bio-composites
Why incorporate Kenaf fiber into bio-composites?
Our company is a young company — we’re trying to commercialize structural fiber and I think so far we have solved two of the big problems: weak bonding between fiber and matrix and degrading properties after exposure to water. When it comes to composites, the fiber reinforces the plastic resin, and carries the majority of the load, while the plastic matrix holds it all together and transfers load from one fiber to another. Natural fibers are pretty strong and stiff, and if you look at their properties — they look pretty good compared to fiberglass, especially on a weight basis — it really has a lot of potential, except that people have not been able to translate these fiber properties into very good composite-material properties. This problem is directly related to the strength of the bond between the fiber and the matrix. And the problem is much worse after soaking in water.
What are the challenges?
You always have the weak interface issue, and that weak interface issue is even worse once you get the fiber wet. If you don’t have a good connection — that good interface — then you don’t have a good composite material. What we’re doing is using a chemistry approach we call a ”In-Situ Polymeric Coating”, or “IPC” for short. We can’t talk much about it since we are still developing our patent strategy. But essentially we put some chemistry on the fiber and solve that moisture issue, while also enhancing the fiber-to-matrix bond strength. And, we believe, once we fully develop this thing, it will enable natural fibers to replace fiberglass in many structural applications.
Why did you choose Kenaf fiber over other bast fibers?
Kenaf, in particular, is very good for the soil. It has been used in the past for soil remediation. It doesn’t require much fertilizer, unlike corn, cotton and many other plants that require allot of fertilizers and pesticides. Kenaf grows 12 to 15 feet tall in a three or four month growing season. Also, one acre of cultivated kenaf soaks up three times as much carbon dioxide as a one acre of rain forest. And the fiber from the kenaf plant is strong and light weight. Right now the fiberglass composites industry is trying to get the automotive industry to make cars out of composites instead of metal — for example, instead of steel fenders, the composites industry is trying to get companies to use fiberglass composite fenders. One of the key drivers for our products is that they can reduce weight. Every pound you can save on the car translates to fuel savings. Kenaf is less dense than fiber glass. Other bio fibers such as jute, hemp and flax are also strong but light weight. However these plants don’t grow as fast as kenaf in most North American climates. For example, Jute, hemp and kenaf are cousins, but jute grows in swamps. There’s not that much swampland in the United States. And it’s illegal to grow hemp in the US. While our IPC treatment will work on most natural fibers, we think Kenaf is a better product long term.