International Collaboration and Competitive Rivalry Push FPL Scientists to Excellence

There was nothing earth-shattering found—though some hypotheses were discarded and new research launching points were identified. And that’s extremely important because science, research and development are not linear. Sometimes there isn’t a “Eureka!” moment, just insatiable curiosity, grit and determination that push scientists to explore and discover the unknown.

And sometimes there’s a very human element that pushes scientific discovery—healthy human rivalry.

That’s the exciting part of this story—it’s what readers won’t learn from the recent publication from Forest Products Laboratory (FPL) researchers, “Effects of Wood Moisture Content and the Level of Acetylation on Brown Rot Decay.”

Samuel Zelinka
Supervisory Materials Research Engineer

In the world of wood moisture science, there are very few scientists at the top. FPL’s Samuel Zelinka is one of the top scientists in his field. In Denmark, Emil Thybring, another top wood moisture researcher, is challenging Zelinka. Both are trying to puzzle out one crucial question—why wood moisture behaves the way it does in acetylated wood.  

Why is wood moisture science so important?

Knowing how to control moisture in wood is literally the difference between keeping timber made products standing versus collapsing into a decaying heap. Without knowing how to control moisture, “King Tut’s sarcophagus wouldn’t be around for us to marvel at,” explained Zelinka.

It’s not exactly like Edison versus Tesla because they are friends now, but their relationship did start competitively. Zelinka met Thybring through a mutual colleague and they have been collaborating and telling each other “you’re wrong” ever since.

In fact, Thybring is used as a resource in their recent publication. But that’s the heart of science, it doesn’t happen in a vacuum. Science requires teamwork and collaboration to advance.

And with that in mind, Zelinka carefully picked his research team knowing that he had his own strengths and weaknesses. He chose FPL researchers Grant Kirker, Amy Bishell, and Samuel Glass, all who had strengths that complimented each other as a team.

So, what was this super-team of FPL researchers looking for?

They were trying to answer the question of whether acetylated wood decays less from fungi because of its lower moisture content or if there are additional antifungal effects from the chemical process of acetylating wood. 

How is acetylated wood made and what makes it so special?

Kiln dried timber is soaked in a bath of acetic anhydride, an organic compound related to vinegar. After its dried from its bath, acetylated wood sometimes smells like pickles.

But hold your horses, pickle lovers. Sadly, there won’t be any scratch and sniff acetylated wood with which to build fragrant pickle furniture. A few days after acetylation, the wood loses its pickled smell.

However, acetylation does fundamentally change the cellular structure of wood which also changes the properties of wood. Higher wood density, lower moisture content, and greater wood decay resistance are just a few of the more notable changes that acetylation makes to wood.  

And because acetylation so fundamentally modifies wood, the process makes it a less appealing snack for fungi that cause wood decay. But the crux of acetylated wood is the how and why.

Acetylated wood is mysterious and to-date researchers don’t have a complete understanding of how acetylation prevents decay. However, with a better understanding of its properties, it’s production costs could be competitive with other timber products that are currently available. And because the chemical to create acetylated wood is non-toxic at the levels it needs for production, it has many market advantages. Acetylated wood has already been used for several decades in Europe, where regulations are stricter on chemically treated timber. With the world looking for greener solutions, acetylated wood has an advantage over other chemically treated products because it can be disposed of easily at end of life.  

Their lab is full of small bottles the size of spice jars, and each jar is filled with soil, specific species of fungi, and cubes of acetylated wood. The bottles are carefully handled to prevent cross-contamination. Pops of smell color the lab with tangy vinegar, warm petrichor, and robust mushroom as FPL researchers meticulously checked their sample bottles and conducted the painstaking minutiae of searching for the unknown.  

What they are left with are tantalizing leads to future exploration. Long term field tests to confirm service life of acetylated wood are already in the planning stages at FPL. Kirker also explained, “Acetylation represents a good theoretical model for future study and helps us understand that depending on how we manipulate or modify the characteristics of wood, we can make it better for severe applications such as ground contact and marine exposure.

And what does the future hold for Zelinka and Thybring? The question of how acetylation changes the cellular function of moisture in acetylated wood still awaits—and so does a lot of debate, exchanging of ideas, and healthy arguments.

To find out more about the amazing advancements our scientists are making, visit the Forest Products Laboratory at: