Current Research

Dr. Frihart is engaged with building bridges between applied and fundamental research, industry and academics, nano-scale processes and macro-scale properties, chemical structures and polymer properties between the United States and foreign researchers. His main area of interest is in adhesives, but the interaction of chemicals with wood has important value from his perspective.

The 25 years of professional experience that he brings from working in industry on the development of new processes and products has led to a strong belief in team efforts and the fundamentals that serve as the basis for problem solving within the commercial products arena.His involvement in the following FPL research teams includes:

• Working with University of Wisconsin professors and the use of advanced nuclear magnetic resonance spectroscopy and nanoindentation to better under wood adhesion fundamentals.
• Working with outside companies which has led to new technology for soybean-based adhesives that are being used commercially.
• Assisting the Department of Defense on improving binders for primers used in small caliber ammunition.

Dr. Frihart is motivated by the challenges of science and bringing value to the public.

Research Interests

• Analysis of wood bonds
• Analytical chemistry of wood adhesives
• Bio-based adhesives
• Mechanisms of adhesive bonding
• Performance of wood adhesives
• Wood adhesive chemistry

Education

• Columbia University, Chemistry Department, Postdoctoral Post Doc 1976
• University of Illinois, Champaign/Urbana, Ph.D. Bio-organic Chemistry 1973
• University of Illinois, Champaign/Urbana, M.S. Bio-organic Chemistry 1971
• University of Wisconsin, Madison, B.S. Organic Chemistry 1969

Featured Publications & Products

• Wescott, James; Frihart, Charles. 2011. Sticking power from soya beans : higher fossil fuel prices and concerns over formaldehyde in existing glue formulations have led to a resurgence in interest in soya-based adhesives, report.
• Yelle, Daniel J.; Ralph, John; Frihart, Charles R. 2011. Delineating pMDI model reactions with loblolly pine via solution-state NMR spectroscopy. Part 2, Non-catalyzed reactions with the wood cell wall.
• Yelle, Daniel J.; Ralph, John; Frihart, Charles R. 2011. Delineating pMDI model reactions with loblolly pine via solution-state NMR spectroscopy. Part 1, Catalyzed reactions with wood models and wood polymers.
• Frihart, Charles R. 2010. Soy protein adhesives.

Patents

• Wescott, James M.; Frihart, Charles R. 2008. Water-Resistant Vegetable Protein Adhesive Dispersion Compositions.
• Weimer, Paul; Lorenz, Linda; Conner, Anthony; Frihart, Charles. 2010. Wood Adhesives Containing Solid Residues of Biomass Fermentations.

Publications

• Frihart, Charles R.; Brandon, Rishawn ; Ibach, Rebecca E.; Hunt, Christopher G.; Gindl-Altmutter, Wolfgang . 2021. Comparative Adhesive Bonding of Wood Chemically Modified with either Acetic Anhydride or Butylene Oxide.
• Kutnar, Andreja ; O’Dell, Jane ; Hunt, Christopher ; Frihart, Charles ; Kamke, Frederick ; Schwarzkopf, Matthew . 2021. Viscoelastic properties of thermo-hydro-mechanically treated beech (Fagus sylvatica L.) determined using dynamic mechanical analysis.
• Frihart, Charles; Hunt, Christopher. 2021. Wood adhesives: bond formation and performance.
• Frihart, Charles R.; Chaffee, Timothy L.; Wescott, James M. 2020. Long-term formaldehyde emission potential from UF- and NAF-bonded particleboards.
• Jakes, Joseph E.; Zelinka, Samuel L.; Hunt, Christopher G.; Ciesielski, Peter ; Frihart, Charles R.; Yelle, Daniel ; Passarini, Leandro ; Gleber, Sophie-Charlotte ; Vine, David ; Vogt, Stefan . 2020. Measurement of moisture-dependent ion diffusion constants in wood cell wall layers using time-lapse micro X-ray fluorescence microscopy.
• Frihart, Charles R.; Lorenz, Linda . 2020. Standard test method ASTM D 7998-19 for the cohesive strength development of wood adhesives.
• Frihart, Charles R.; Hunt, Christopher G.; Plaza, Nayomi Z.; Jakes, Joseph E. 2019. Adhesive-wood interactions in relation to failure in bonded wood products from the centimeter to nanometer scale.
• Frihart, Charles R.; Pizzi, Antonio ; Xi, Xuedong ; Lorenz, Linda F. 2019. Reactions of soy flour and soy protein by non-volatile aldehydes generation by specific oxidation.
• Frihart, Charles R.; Lorenz, Linda F. 2019. Specific oxidants improve the wood bonding strength of soy and other plant flours.
• Hunt, Christopher G.; Zelinka, Samuel L.; Frihart, Charles R.; Lorenz, Linda ; Yelle, Daniel ; Gleber, Sophie-Charlotte ; Vogt, Stefan ; Jakes, Joseph E. 2018. Acetylation increases relative humidity threshold for ion transport in wood cell walls a means to understanding decay resistance.
• Jakes, Joseph E.; Frihart, Charles R.; Hunt, Christopher G.; Yelle, Daniel J.; Plaza, Nayomi Z.; Lorenz, Linda F.; Ching, Daniel J. 2018. Integrating multiscale studies of adhesive penetration into wood.
• Frihart, Charles R.; Lorenz, Linda F. 2018. Protein adhesives.
• Hunt, Christopher G.; Frihart, Charles R.; Dunky, Manfred ; Rohumaa, Anti . 2018. Understanding wood bonds going beyond what meets the eye: a critical review.
• Frihart, Charles ; Zylkowski, Steve . 2018. Volatile organic compounds emissions from North American engineered wood products.
• Jakes, Joseph E.; Frihart, Charles R.; Hunt, Christopher G.; Yelle, Daniel J.; Plaza, Nayomi Z.; Lorenz, Linda ; Grigsby, Warren ; Ching, Daniel J.; Kamke, Fred ; Gleber, Sophie-Charlotte ; Vogt, Stefan ; Xiao, Xianghui . 2018. X-ray methods to observe and quantify adhesive penetration into wood.
• Frihart, Charles; Brandon, Rishawn; Beecher, James; Ibach, Rebecca. 2017. Adhesives for Achieving Durable Bonds with Acetylated Wood.
• Hunt, Christopher G.; Jakes, Joseph; Frihart, Charles. 2017. Advanced analysis tools and programs to accelerate the adoption of more natural structures.
• Jakes, Joseph E.; Plaza-Rodriguez, Nayomi; Arzola Villegas, Xavier; Frihart, Charles R. 2017. Improved understanding of moisture effects on outdoor wood adhesive bondlines.
• Jakes, Joseph E.; Frihart, Charles R.; Hunt, Christopher G.;  Yelle, Daniel J.; Plaza, Nayomi ; Lorenz, Linda ; Ching, Daniel J. 2017. Integrating multi-scale studies of adhesive penetration into wood.
• Baglayeva, Ganna; Seames, Wayne S.; Frihart, Charles R.; O'Dell, Jane; Kozliak, Evguenii I. 2017. Penetration of n-hexadecane and water into wood under conditions simulating catastrophic floods.
• Plaza, Nayomi Z.; Jakes, Joseph E.; Frihart, Charles R.; Hunt, Christopher G.; Yelle, Daniel J.; Lorenz, Linda F. 2017. Small angle neutron scattering as a tool to evaluate moisture-induced swelling in the nanostructure of chemically modified wood cell walls.
• Plaza, Nayomi Z.; Jakes, Joseph E.; Frihart, Charles R.; Hunt, Christopher G.; Yelle, Daniel J.; Lorenz, Linda F.; Heller, William T.; Pingali, Sai Venkatesh; Stone, Donald S. 2017. Small-angle neutron scattering as a new tool to evaluate moisture-induced swelling in the nanostructure of chemically modified wood cell walls.
• Zylkowski, Steve; Frihart, Charles. 2017. Volatile organic compound emissions from engineered wood products.
• Frihart, Charles R. 2016. Adhesive Penetration of Wood and Its Effect on Bond Strength.
• Frihart, Charles R. 2016. Cohesion and Adhesion with Proteins.
• Rohumaa, Anti; Yamamoto, Akio; Hunt, Christopher G.; Frihart, Charles R.; Hughes, Mark; Kers, Jaan. 2016. Effect of log soaking and the temperature of peeling on the properties of rotary-cut birch (Betula pendula Roth) veneer bonded with phenol-formaldehyde adhesive.
• Frihart, Charles R.; Beecher, James F. 2016. Factors that lead to failure with wood adhesive bonds.
• Frihart, Charles R.; Birkeland, Michael J. 2016. From the lab to commercial reality with biobased adhesives for wood.
• Frihart, Charles R.; Coolidge, Thomas; Mock, Chera; Valle, Eder. 2016. High bonding temperatures greatly improve soy adhesive wet strength.
• Baglayeva, Ganna; Krishnamoorthy, Gautham; Frihart, Charles R.; Seamus, Wayne S.; O’Dell, Jane; Kozliak, Evguenii. 2016. Modeling of n-hexadecane and water sorption in wood.
• Frihart, Charles R. 2016. Potential for Biobased Adhesives in Wood Bonding.
• Frihart, Charles R.; Birkeland, Michael. 2016. Soy Products for Wood Bonding.
• Rohumaa, Anti; Antikainen, Toni; Hunt, Christopher G.; Frihart, Charles R.; Hughes, Mark. 2016. The influence of log soaking temperature on surface quality and integrity performance of birch (Betula pendula Roth) veneer.
• Lorenz, Linda; Birkeland, Michael; Daurio, Chera; Frihart, Charles R. 2015. Soy Flour Adhesive Strength Compared with That of Purified Soy Proteins*.
• Jakes, Joseph E.; Hunt, Christopher G.; Yelle, Daniel J.; Lorenz, Linda; Hirth, Kolby; Gleber, Sophie-Charlotte; Vogt, Stefan; Grigsby, Warren; Frihart, Charles R. 2015. Synchrotron-based X-ray Fluorescence Microscopy in Conjunction with Nanoindentation to Study Molecular-Scale Interactions of Phenol Formaldehyde in Wood Cell Walls.
• Frihart, Charles R.; Yelle, Daniel J.; Ibach, Rebecca E. 2015. Wood properties influence bond durability.
• Frihart, Charles R.; Hunt, Christopher G.; Birkeland, Michael J. 2014. Chapter 16: Soy Proteins as Wood Adhesives.
• Frihart, Charles R.; Birkeland, Michael J. 2014. Chapter 8: Soy Properties and Soy Wood Adhesives.
• Chen, Yao; Stark, Nicole M.; Cai, Zhiyong; Frihart, Charles R.; Lorenz, Linda F.; Ibach, Rebecca E. 2014. Chemical Modification of Kraft Lignin: Effect on Chemical and Thermal Properties.
• Frihart, Charles R. 2014. Many Roles of Wood Adhesives.
• Frihart, Charles R.; Satori, Holly; Rongxian, Zhu; Birkeland, Michael J. 2014. Ovalbumin as a Wood Adhesive.
• Rohumaa, Anti; Hunt, Christopher G.; Frihart, Charles R.; Saranpää, Pekka; Ohlmeyer, Martin; Hughes, Mark. 2014. The influence of felling season and log-soaking temperature on the wetting and phenol formaldehyde adhesive bonding characteristics of birch veneer.
• Frihart, Charles R. 2013. Chapter 9:Wood Adhesion and Adhesives.
• Frihart, Charles R.; Lorenz, Linda F. 2013. Comparing Soy Flour Wood Adhesives to Purified Soy Protein Adhesives.
• Park, Byung-Dae; Frihart, Charles R.; Yu, Yan; Singh, Adya P. 2013. Hardness evaluation of cured urea-formaldehyde resins with different formaldehyde/urea mole ratios using nanoindentation method.
• O’Dell, Jane L.; Hunt, Christopher G.; Frihart, Charles R. 2013. High temperature performance of soy-based adhesives.
• Frihart, Charles R. 2013. How wood adhesives work and where are the areas for improvement.
• Chen, Yao; Frihart, Charles R.; Cai, Zhiyong; Lorenz, Linda F.; Stark, Nicole M. 2013. Lignin-based Phenol-Formaldehyde Resins from Purified CO2 Precipitated Kraft lignin (PCO2KL).
• Chen, Yao; Frihart, Charles R.; Cai, Zhiyong; Lorenz, Linda F.; Stark, Nicole M. 2013. Lignin-based Phenol-Formalehyde Resins from Purified CO2 Precipitated Kraft Lignin (PCO2KL).
• Frihart, Charles R.; Lorenz, Linda. 2013. Protein Modifiers Generally Provide Limited Improvement in Wood Bond Strength of Soy Flour Adhesives.
• Frihart, Charles R.; Satori, Holly. 2013. Soy flour dispersibility and performance as wood adhesive.
• Rohumaa, Anti; Hunt, Christopher G.; Hughes, Mark; Frihart, Charles R.; Logren, Janne. 2013. The influence of lathe check depth and orientation on the bond quality of phenol-formaldehyde-bonded birch plywood.
• Xu, Yuzhi; Wang, Chunpeng; Chu, Fuxiang; Frihart, Charles R.; Lorenz, Linda F.; Stark, Nicole M. 2012. Chemical Modification of Soy Flour Protein and its Properties.
• Frihart, Charles R.; Wescott, James M.; Chaffee, Timothy L.; Gonner, Kyle M. 2012. Formaldehyde Emissions from Urea-Formaldehyde- and no-added-formaldehyde-Bonded particleboard as Influenced by Temperature and Relative Humidity.
• Frihart, Charles R. 2011. Influence of soy type on wood bonding performance.
• Jakes, Joseph E.; Yelle, Daniel J.; Frihart, Charles R. 2011. Tools to Understand Structural Property Relationships for Wood Cell Walls.
• Frihart, Charles R. 2011. Wood adhesives : vital for producing most wood products.
• Frihart, Charles R.; Hunt, Christopher G. 2010. Adhesives with wood materials : bond formation and performance.
• Frihart, Charles. 2010. Biobased adhesives and non-conventional bonding.
• Yelle, Daniel J.; Jakes, Joseph E.; Ralph, John; Frihart, Charles R. 2010. Characterizing polymeric methylene diphenyl diisocyanate reactions with wood. 1, High-resolution solution-state NMR spectroscopy.
• Jakes, J.E.; Yelle, D.Y.; Beecher, J.F.; Frihart, C.R.; Stone, D.S. 2010. Characterizing polymeric methylene diphenyl diisocyanate reactions with wood. 2, Nano-indentation.
• Birkeland, Michael J.; Lorenz, Linda; Wescott, James M.; Frihart, Charles R. 2010. Determination of native (wood derived) formaldehyde by the desiccator method in particleboards generated during panel production.
• Frihart, Charles R.; Wescott, James M.; Birkeland, Michael J.; Gonner, Kyle M. 2010. Formaldehyde emissions from ULEF- and NAF-bonded commercial hardwood plywood as influenced by temperature and relative humidity.
• Moon, Robert J.; Wells, Joseph; Kretschmann, David E.; Evans, James; Wiedenhoeft, Alex C.; Frihart, Charles R. 2010. Influence of chemical treatments on moisture-induced dimensional change and elastic modulus of earlywood and latewood.
• Jakes, Joseph E.; Frihart, Charles R.; Beecher, James F.; Stone, Donald S. 2010. Nano-indentation creep properties of the S2 cell wall lamina and compound corner middle lamella abstract.
• Frihart, Charles R.; Birkeland, Michael J.; Allen, Anthony J.; Wescott, James M. 2010. Soy adhesives that can form durable bonds for plywood, laminated wood flooring, and particleboard.
• Jakes, Joseph E.; Frihart, Charles R.; Stone, Donald S. 2009. Creep properties of micron-size domains in ethylene glycol modified wood across 4 1/2 decades in strain rate.
• Frihart, Charles R. 2009. Adhesive groups and how they relate to the durability of bonded wood.
• Frihart, Charles R.; Dally, Brice N.; Wescott, James M.; Birkeland, Michael J. 2009. Bio-based adhesives and reproducible rapid small-scale bond strength testing.
• Hunt, Christopher G.; Frihart, Charles; O'Dell, Jane. 2009. Heat resistant soy adhesives for structural wood products.
• Yelle, Daniel J.; Ralph, John; Frihart, Charles R. 2009. Investigating the reactivity of pMDI with wood cell walls using high-resolution solution-state NMR spectroscopy.
• Jakes, J.E.; Frihart, C.R.; Beecher, J.F.; Moon, R.J.; Resto, P.J.; Melgarejo, Z.H.; Saurez, O.M.; Baumgart, H.; Elmustafa, A.A.; Stone, D.S. 2009. Nanoindentation near the edge.
• Moon, Robert J.; Jakes, Joseph E.; Beecher, Jim F.; Frihart, Charles R.; Stone, Donald S. 2009. Relating nanoindentation to macroindentation of wood.
• Yelle, Daniel J.; Ralph, John; Frihart, Charles R. 2008. Characterization of nonderivatized plant cell walls using high-resolution solution-state NMR spectroscopy.
• Frihart, Charles R.; Yelle, Daniel J.; Ralph, John; Moon, Robert J.; Stone, Donald S.; Jakes, Joseph E. 2008. Enhanced understanding of the relationship between chemical modification and mechanical properties of wood.
• Jakes, Joseph E.; Frihart, Charles R.; Beecher, James F.; Moon, Robert J.; Stone, D. S. 2008. Experimental method to account for structural compliance in nanoindentation measurements.
• Jakes, Joseph E.; Stone, Donald S.; Frihart, Charles R. 2008. Nanoindentation methods for wood-adhesive bond lines.
• Frihart, Charles R.; Yelle, Daniel J.; Wiedenhoeft, Alex C. 2008. What does moisture-related durability of wood bonds mean.
• Frihart, Charles R.; Wescott, James M. 2008. Why do some wood-adhesive bonds respond poorly to accelerated moisture-resistant tests.
• Lorenz, Linda F.; Frihart, Charles R.; Wescott, James M. 2007. Chromatographic analysis of the reaction of soy flour with formaldehyde and phenol for wood adhesives.
• Frihart, Charles R.; Wescott, James M.; Traska, Amy E. 2007. Dispersion adhesives from soy flour and phenol formaldehyde.
• Frihart, Charles R. 2007. Model for understanding the durability performance of wood adhesives.
• Jakes, Joseph E.; Stone, Donald S.; Frihart, Charles R. 2007. Nanoindentation size effects in wood.
• Wescott, James M.; Birkeland, Michael J.; Traska, Amy E.; Frihart, Charles R.; Dally, Brice N. 2007. New method for rapid testing of bond strength for wood adhesives.
• Hunt, Christopher G.; Brandon, Rishawn; Ibach, Rebecca E.; Frihart, Charles R. 2007. What does bonding to modified wood tell us about adhesion.
• Frihart, Charles R. 2007. Why good ideas and good science do not always make it into the marketplace.
• Lorenz, Linda F.; Frihart, Charles. 2006. Adhesive bonding of wood treated with ACQ and copper azole preservatives.
• Frihart, Charles R.; Chandler, Jermal G. 2006. Can melamine-based wood primers help in understanding bonded wood durability.
• Hofferber, Blake M.; Kolodka, Edward; Brandon, Rishawn; Moon, Robert J.; Frihart, Charles R. 2006. Effects of swelling forces on the durability of wood adhesive bonds.
• Moon, Robert J.; Frihart, Charles R.; Wegner, Theodore. 2006. Nanotechnology applications in the forest products industry.
• Frihart, Charles R. 2006. Wood structure and adhesive bond strength.
• Frihart, Charles R. 2005. Adhesive bonding and performance testing of bonded wood products.
• Lorenz, Linda; Frihart, Charles R.; Wescott, James M. 2005. Analysis of soy flour/phenol-formaldehyde adhesives for bonding wood.
• Frihart, Charles R. 2005. Are epoxy-wood bonds durable enough.
• Chandler, Jermal G.; Frihart, Charles R. 2005. Assessment of increased wet wood bonding for epoxy-bonded samples using a melamine-urea-formaldehyde priming agent.
• Wescott, James M.; Traska, Amy; Frihart, Charles R.; Lorenz, Linda. 2005. Durable soy-based adhesive dispersions.
• Brandon, Rishawn; Ibach, Rebecca E.; Frihart, Charles R. 2005. Effects of chemically modified wood on bond durability.
• Chandler, Jermal G.; Brandon, Rishawn L.; Frihart, Charles R. 2005. Examination of adhesive penetration in modified wood using fluorescence microscopy.
• Frihart, Charles R. 2005. Utility of Horioka s and Marra s models for adhesive failure.
• Frihart, Charles R. 2005. Wood adhesion and adhesives.
• Weimer, P. J.; Koegel, R. G.; Lorenz, Linda F.; Frihart, Charles R.; Kenealy, William R. 2005. Wood adhesives prepared from lucerne fiber fermentation residues of Ruminococcus albus and Clostridium thermocellum.
• Beecher, James F.; Frihart, Charles R. 2005. X-ray photoelectron spectroscopy for characterization of wood surfaces in adhesion studies.
• Frihart, Charles R. 2004. Adhesive interactions with wood.
• Wescott, James M.; Frihart, Charles R. 2004. Competitive soybean flour/phenol-formaldehyde adhesives for oriented strandboard.
• Frihart, Charles R.; Wescott, James M. 2004. Improved water resistance of bio-based adhesives for wood bonding.
• Frihart, Charles R. 2004. Specific adhesion model for bonding hot-melt polyamides to vinyl.
• Frihart, Charles R. 2004. The challenge of bonding treated wood.
• Frihart, Charles R. 2003. Durable wood bonding with epoxy adhesives.
• Frihart, Charles R. 2003. Interaction of copper wood preservatives and adhesives.

Research Highlights

Highlight	Title	Year
FPL-2010-001	Centennial Edition, Wood Handbook—Wood as an Engineering Material The Wood Handbook—Wood as an Engineering Material serves as a primary reference document for a wide variety of users-from the general publ ...	2010
FPL-2012-01	Do Not Blame Adhesives When Veneers Are Guilty Perfectly good adhesives may be wrongly discarded after failing a performance test when in actuality the veneer caused the failure.	2012
FPL-2016-67	New Test of Raw Material Quality Improves the Strength of Wood Laminates Plywood and laminated veneer lumber are built from wood veneers. Because the test for surface quality of the veneer was not very useful, Forest ...	2016
FPL-2017-94	Soy adhesives resolve two problems at once Lower formaldehyde emission bonded wood products can be made using plant-based adhesives through an industry-government partnership.	2017
FPL-2010-024	Soy-Based Adhesives Provide Wood Composites That Meet California Emission Standards Ashland- Hercules, working cooperatively with the Forest Products Laboratory, have developed these soy adhesives and have commercialized them fo ...	2010
FPL-2011-23	Soy-based Adhesives for Wood Products Soy-based adhesives developed at FPL have been commercialized and allow wood manufacturers to replace adhesives based on fossil fuel with biomas ...	2011
FPL-2013-137	Success of Wood Veneers Influenced by Harvesting Season and Temperature: Plywood Performance and Failure: A New Understanding Cooperation with Finnish researchers results in new understanding of relationships between veneer processing, veneer properties, and product fai ...	2013
FPL-2016-72	Using Soybeans to Replace Synthetic Adhesives for Wood Bonding Soybeans were used to glue the first plywood but were replaced by fossil-fuel-based adhesives after World War II. Scientists at the Forest Servi ...	2016
FPL-2018-21	X-Ray Methods to Observe and Quantify Adhesive Penetration into Wood To accelerate development of new and improved wood adhesives for engineered wood products, researchers are working to understand the optimal adh ...	2018