FPL Scientist Reflects on 20 Years with the Lab

Charles Frihart – or Chuck, as he prefers to be called – has just retired after 20 years with the Forest Products Laboratory. Before that, he worked in industry even longer. The total experience has left him with a unique perspective.

“Before FPL, I spent most of my time in New Jersey,” Chuck reminisced. Even though he lived and worked there for most of his career, Chuck says that he and his family always said we were temporary residents of New Jersey, “because we always considered Wisconsin home.”

Chuck started out working for a pulp and paper company. He then joined Henkel, which is the world’s largest adhesive company.

Chuck says he was happy to have the opportunity to return to Wisconsin in 2001 to work at FPL. His job was to modernize the wood adhesive group through his knowledge of adhesives in non-wood fields.

When paper pulp is manufactured, lignin and other parts of the wood are removed to release cellulose fibers. These byproducts form “black liquor,” which is seven times more abundant than the final paper pulp. This material is concentrated and put through a recovery boiler to recycle the pulping chemicals and provide energy. The pulping by-products are converted into chemicals for adhesives, printing inks, fragrances, and other products.

In industry, Chuck worked on what to do with chemical byproducts from the pulping process.

Charles Frihart at work in the Forest Products Laboratory

“I was mainly working with the fatty acids and what to do with them,” explained Chuck. “Fatty acids are similar to hydrolyzed vegetable oil. Basically, I was working on adhesives for many applications and generated 29 patents.”

Chuck’s interest in bio-based compounds goes back to his college days.

“I’ve always studied these natural products from my work on nucleic acids in college, through industry work on fatty and rosin acids, and at FPL on protein adhesives.

“I was hired at FPL not because I knew a lot about wood adhesives, but because I knew adhesives in general,” Chuck continued. “I was also brought in because FPL wanted someone with a different perspective, which meant being comfortable with working in industry.

“Most of my years with the paper industry, we had a very good executive vice president who wanted people to do a combination of applied and fundamental research. Sometimes you have people who are very good at fundamental research and spend all their time doing it, but have no idea how to make useful products, and the people in industry tend to get so attached to doing the applied work, that they forget fundamental science, so you have to think on both levels, because they’re not mutually exclusive.

“They complement one another and you can make more progress when you combine the two. My goal has always been to make something new, but at the same time understand the fundamentals as well as I can, and not get tied up in either one.

“Trial and error only gets you so far, so my thing has been to really understand how wood adhesives work and why they fail. Wood adhesives don’t normally fail except under wet conditions, and in some cases, with some of the adhesives applications, you also need temperature resistance, as in a fire, and that was a problem.”

The adhesives group needed a team of  specialists in material science, analytical chemistry, mechanics and wood chemistry. The first addition involved Chuck’s welcoming Daniel Yelle, who does adhesive chemical reactions with wood polymers and lignin chemistry. “We have studied lignin, but few people have figured out how to get useful adhesive products out of lignin,” explained Chuck. “Although there have been about 200-some papers that have claimed that success, it’s actually only used marginally on a commercial level.

 “The other area for bio-based adhesives is proteins, and soy beans specifically,” said Chuck. “Besides oil and protein food products, it’s basically used as animal food. We don’t produce much tofu or other kinds of fermented soy-based products for people as they do in China and other parts of East Asia. Also, soybeans have a high percentage of lysine, which is an amino acid and an important nutrient for animals.”

Chuck said that it is very difficult to understand proteins in adhesive applications because proteins can change properties very easily, and it’s hard to measure when the properties of proteins change. Chuck pointed out that soy is the major product that has been used in interior wood adhesives in the United States for over 10 years.

Among the major accomplishments in wood adhesives at FPL, Chuck points to the work of Joseph Jakes and Nayomi Plaza Rodriguez, “because they have developed an understanding of the fundamental structure of wood cell walls.”

Joseph works with Argonne National Laboratory, and Nayomi works with Oakridge National Laboratory, both run by the Department of Energy. Chuck said that the major advantage to these collaborations is that the other labs have extremely expensive experimental equipment and allow FPL scientists to write proposals and have access to it. “What makes us different is that we combine chemical probes made by Linda Lorenz with the analysis of wood cell walls to understand how adhesives react with wood itself,” said Chuck.

“The real challenge with adhesives is that they typically only work well only under dry conditions. It’s when things get wet that many of the adhesives fall apart and you have joints coming apart on wood products, et cetera. And so you have to understand the wood swelling and shrinking properties and how it’s doing that, and what Joseph and Nayomi and the others have done is just fantastic. So I can’t claim credit; I had the concept, but I didn’t know how to do it, so my role was more of an instigator, rather than the person who figured out how to do it. And it made FPL the leader in understanding wood cell walls and the behavior of wood.

“FPL is fortunate to have a core of very bright young scientists who can carry us through for the next few decades and who are doing things that nobody else is doing.

“At a certain point,” Chuck said wistfully, “your science becomes dated, and you need to be replaced by people who have different knowledge and abilities of how to carry out science. I’ve enjoyed the science and the people at FPL. Being involved in science is in my blood and will continue, just on a lower priority.”


Throwback Thursday: Paper Pioneers

One early major accomplishment of the Forest Products Laboratory and the Forest Service’s Southern Research Station was cooperative research with industry to develop a way to economically convert southern pine softwood to pulp for newsprint and bleached paper.

Click to enlarge in Flickr.

Click to enlarge in Flickr.

Later a polysulfide process to produce higher yields from southern pine and other softwoods was developed, and today the use of southern pine pulp is a multi-billion dollar industry.

FPL also pioneered the development of multistage bleaching methods for southern pine sulfate pulp. The commercial production of bleached sulfate pulp suitable for bond, writing, wrapping, printing, and specialty papers now amounts to millions of tons annually. Results of this research have helped keep the cost of paper low.

(Excerpt from John Koning’s book Forest Products Laboratory 1910-2010: Celebrating a Century of Accomplishments.)

Women’s History Month: FPL Remembers Marguerite Sykes

Is paper one of the first things that comes to mind when you think about forest products? FPL has been at the forefront of developing innovative and environmentally friendly methods for producing this ubiquitous product. Chemist Marguerite Sykes, who worked in FPL’s pilot plant from 1971 until her retirement in 2002, was a key player in paper pulping research and development.

Sykes-pulping

Marguerite Sykes makes handsheets of paper for evaluation in the paper test laboratory by using experimental pulps. (1980s)

The challenge for FPL scientists has been to economically and sustainably increase the yield of pulp from wood. FPL developed a pulping process that significantly increased pulp yield and allowed use of many underutilized hardwoods. Research at FPL also improved the sulfate (kraft) pulping process so that many softwoods could be used in paper making. These practices have extended timber supply and enhanced forest management.

During her tenure at FPL, Sykes worked on many interdisciplinary teams and co-authored nearly 60 papers. In an interview with the University of Wisconsin U.S. Forest Products Lab Centennial Oral History Project, Sykes speaks with passion for that work: “I think everything I worked on the last fifteen years [was] extraordinarily exciting and I think they were kind of breakthrough topics [such as how] to replace the chemicals for pulping and bleaching and recycling with more environmentally sound methods like enzymes or hydrogen peroxide for bleaching. And so everything was new, and although some people had been doing it, none of these techniques were being used commercially. So it was just kind of ground work on some of these things that made it very exciting.”

Sykes speaks more about how this work came to be. From the mid-1980s through the 1990s, “recycling became big just because landfills were being filled so rapidly,” and people threw out an enormous amount of paper. In addition to recycling work, Sykes felt that existing recycling processes used an excess of chemicals that were “very harmful to the [effluent] waters that came out of the mill.” These chemicals, she says, were defeating any environmental benefits. For this reason, Sykes and others “started using enzymes for de-inking, and that too is an innovative idea.”

Sykes also talks about making handsheets, where in the test lab, “you slurry the pulp and there is a special instrument of sheet mold that you make a hand sheet and all the tests are brightness, how white it is, how strong it is, how easy it tears go back to the basic hand sheet.”

Paper. It’s all around us. FPL thanks this innovative and enthusiastic scientist for her work in improving paper production.