Poster Abstracts. 1. Evaluating the Mechanical Properties of Fire Retardant Treated Oriented Strandboard

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1 Poster Abstracts 1. Evaluating the Mechanical Properties of Fire Retardant Treated Oriented Strandboard Joe Hill, Graduate Research Assistant, Mississippi State University (H. M. Barnes, J.E. Winandy) Abstract: In recent years, oriented strandboard (OSB) has become one of the most popular structural panels used in the construction industry. The widespread usage of this versatile product has enabled many manufacturers to find ways to improve its durability and performance to help meet the needs and demands of the market. Fire retardant treatment is one area where many of these product advancements have taken place. This study was enacted to examine the effect fire retardant treatment has on the mechanical properties of OSB panels and also explored different mechanical testing methods to examine what effect specimen width has on mechanical testing results. Test results revealed that FRT treatment did have a negative effect on the bending properties of the tested samples with the control specimens generally performing better than the treated. Additionally, the wider specimens of the sample set were better suited for this test method because of decreased variation and higher strength values when compared to the smaller width specimens. 2. Preservative-treated Wood: A Responsible Consumer Investment Nathan E. Irby, Hofmann PhD Fellow, North Carolina State University. (T. Eric McConnell, Kevin W. Ragon) Abstract: Understanding consumer perceptions is critical in any marketplace. Unfortunately, many studies highlight the domestic consumer s inadequate knowledge of the green benefits of wood products, especially the service life enhancements provided by, and increasingly benign or lowered mammalian toxicity of, 21st century treated wood products. Increasing consumer awareness of the many benefits of using wood, and instilling in consumer mind s that extending the lifespan of wood products through value-added preservative treatment is the ultimate green process, are the Treated Wood Sustainability Team s (TWST) ultimate objectives. The core mission of the TWST is to disseminate technical information to U.S. consumers, and in turn, provide the foundation for consumers to positively perceive treated wood products. Founded in 2009, the team is a collection of academic and industry professionals with over 30 years of experience in the wood products field. Through outreach efforts, the team is expanding consumer knowledge of treated wood products and hopefully providing an advantageous business avenue for the wood preservation industry s future. In summary, it should be fostered by all involved in the industry to continually increase consumer awareness of our efforts to provide safe, healthy, long-term treated wood products for all.

2 3. Enzymatic Significance of the Metabolic Mechanism of Oxalate in the TCA and Glyoxylate Pathways Based on Specific Isolates of the Copper-Tolerant Brown-Rot Basidiomycete, Antrodia radiculosa Katie Jenkins, Graduate Research Assistant, Mississippi State University. (Susan V. Diehl, Carol Clausen) Abstract: Brown-rot fungi produce oxalic acid in large amounts; however, levels of accumulation and function vary by species. Copper-tolerant fungi, like Antrodia radiculosa, produce and accumulate high levels of oxalic acid in response to copper. Oxalic acid biosynthesis in copper-tolerant fungi has been linked to the glyoxylate and tricarboxylic acid (TCA) cycles. Within these two cycles, it has been proposed that oxalate production relies on twelve specific enzymes. In this study, Antrodia radiculosa isolates undergoing decay of untreated and copper treated wood will be used to evaluate enzyme activity in five of the twelve enzymes. The enzyme activity of fumerase, glyoxylate dehydrogenase, isocitrate lyase, malate synthase, and oxaloacetase, will be determined. Gene expression levels will be compared for decay on untreated and copper treated wood to determine if expression is enhanced by the presence of copper. Gene regulation will be correlated to enzyme production in an attempt to establish the pathway involved in oxalic acid production. The overall objective of this study is to gain insight into the biosynthesis of oxalic acid in order to understand the mechanism utilized by varying isolates of Antrodia radiculosa to overcome copper-based wood preservatives. 4. Investigating Novel Treatments of Wood Packaging Materials to Improve Current Phytosanitization Methods Todd E. Johnson, Graduate Research Assistant, Mississippi State University. (Shane C. Kitchens) Abstract: Current phytosanitary measures for wood packaging materials (WPM) include the use of heat treatments, fumigation and irradiation to combat the transport of pests and pathogens through domestic and international shipping. These measures have proven to eliminate pests at the time of application, but none of them provide residual protection following the treatment. An increased awareness of the presence of mold on materials receiving these treatments has compounded the need to provide residual protection. This study tested the hypothesis that a method exists in which initial and residual control of pests, pathogens and surface mold can be achieved through the use of non-leaching antimicrobials in conjunction with other traditional control measures.

3 5. Susceptibility of Lumber Cut from Beetle-Killed Southern Pine Trees to Subterranean Termite Attack Nathan S. Little, Graduate Research Assistant, Mississippi State University. (John J. Riggins, Michael D. Ulyshen, Andy J. Londo, Tor P. Schultz) Abstract: Lumber cut from bark beetle salvaged trees is often inundated with ophiostomatoid blue-stain fungi associated with attacking bark beetles and, thus, has a lowered economic value. Despite the many research projects that have studied causes for bark beetle attack, the exact mechanism(s) is still unknown. During the past year, while examining bark beetle-attacked southern pine trees, we observed that nearly all bark beetle-inhabited trees, including those in the early stages of senescence, had termites in the tree trunk base. Subterranean termites are known to be attracted to extracts of various wood decay fungi. This may indicate that termites are attracted to pine trees containing blue-stain and, consequently, to blue-stained lumber. A series of AWPA E1-09 choice tests was employed to determine the feeding preference of Reticulitermes flavipes for: 1) kiln-dried southern yellow pine (SYP) sapwood with blue-stain versus unstained kiln-dried SYP sapwood and 2) air-dried SYP sapwood with blue-stain versus unstained air-dried SYP sapwood. Results indicate a feeding preference of R. flavipes for both air-dried and kiln-dried blue-stained lumber over unstained controls. 6. Calcium Carbonate Nanoparticle Impregnation of Cellulosic Natural Fiber for Polymer Composites Jinshu Shi, Graduate Research Assistant, Mississippi State University. (Sheldon Q. Shi, Sangyeob Lee, H.M. Barnes) jshi1@cfr.msstate.edu Abstract: The objective of this study was to investigate an inorganic nanoparticle impregnation (INI) technique to improve compatibility between natural fibers and polyolefin matrices. The impregnation targeted the micropores in cell wall structures of the natural fibers. Ionic salts (CaCl2 and Na2CO3) were used to crystallize CaCO3 in fiber cell wall and on fiber surface. Two molar ratios of Na2CO3 to CaCl2 (1:1 and 1:2) and three levels of reaction temperature and autogenous vapor pressure (100 C, 0.15 MPa; 130 C, 0.30 MPa and 160 C, 0.70 MPa) were used to optimize the loading percentage and crystal size of the CaCO3 nanoparticles. The loading percentage and nanoparticle size and its distribution in the fibers were evaluated by ash content measurement and scanning electron microscopy (SEM). The INI treated fibers were applied to reinforce polypropylene composites. The function of the fibers and CaCO3 nanoparticles in polyolefin matrix was also investigated by flexural and tensile testing and thermal analysis. 7. [POSTER WITHDRAWN] Metal Corrosion of Treating Solution and Treated Wood with Different Formulations of ACQ-D Wei Gao, Beijing Forestry University (Jinzhen Cao, Wang Wang)

4 8. Effect of ph value on Chemical Components and Mechanical Properties of Thermallymodified Wood Wang Wang, Beijing Forestry University. (Jinzhen Cao, Futong Cui, Xing Wang) Abstract: In order to investigate the correlation between acidity and degradation during thermal treatment of wood, Cathay poplar (Populus cathayana Rehd.) wood samples were impregnated with solutions of different ph values, which included disodium octoborate tetrahydrate (DOT, ph=8.3), monoethanolamine (MEA, ph=12) and four buffering solutions composed of boric acid and sodium hydroxide (BA/NaOH, ph=6, 7, 8, 9), and then heated for 4h at 180, 200 and 220, respectively. The Bending MOR and MOE, mass losses, ph values, percentages of lignin and hemicelluloses were subsequently determined in thermally-modified samples in comparison with the control samples without pretreatment or/and thermal treatment. The results of the experiments indicated that DOT and buffering solutions reduced the mass loss of thermally-treated wood and had less loss of bending MOR and MOE, while MEA pretreatment increased the mass loss and showed comparable or even lower bending MOR and MOE than the untreated control before or after thermal treatments. The chemical analyses suggested that the degradation of hemicelloses was inhibited by DOT and BA/NaOH pretreatments within the temperature range between 180 and 200,which may explain the improvement on mechanical properties. 9. Effect of Biodiesel on the Efficacy of Pentachlorophenol Treated Wood Saeed Keshani Langroodi, Mississippi State University. (Dr. Hamid Borazjani, Dr. Darrel D. Nicholas, Dr. Lynn Prewitt, Dr. Susan V. Diehl, Dr. Shane Kitchens) Abstract: Pentachlorophenol (PCP) is widely used as a wood preservative for utility poles and other wood products. Research has shown that the solvent carrier system used for PCP plays a major role in the service life of wood products treated with this preservative. A solvent system based on the combination of petroleum diesel and KB3 as a co-solvent has been used for many years and has proven to be a satisfactory system. Recently, it has been proposed that a modified PCP carrier system based on the use of diesel/biodiesel be used in place of the conventional diesel/kb3 carrier. Consequently, an accelerated soil contact decay study was initiated to compare the performance of pine wood treated with the conventional carrier and a modified carrier with biodiesel added, both with and without PCP. After 18 months exposure the data shows that the rate of wood decay is consistently higher for wood treated with diesel/ biodiesel than it is for diesel/kb3. Furthermore, at all four PCP retention levels the rate of decay was greater in diesel/ biodiesel compared to the conventional diesel/kb3 carrier. These results suggest that the use of biodiesel as a co-solvent in PCP treatments may result in a reduction in the service life of treated wood products.

5 10. Copper Penetration of Three Pine Species Pressure Treated with Micronized Copper Azole (MCA) John Rademacher, Graduate Student, Michigan State University. (Pascal Kamdem) Abstract: The use of wood products, if properly treated, is expected to increase energy conservation and decrease the carbon footprint of these products. However, one of the drawbacks of this bioproduct is its variable unpredictable durability against biological, physical, chemical, and mechanical deterioration. Wood preservatives have been used to improve durability of products used in exterior applications, where deterioration is a dilemma. Several chemicals, from creosote to pentachlorophenol and waterborne inorganics such as copperarsenic-chromium-zinc formulations, have had considerable negative impacts on humans and the environment, but have been used for decades. Micronized copper formulations are an emerging concept, which is based on the use of small micron-sized solid particles of copper, dispersed in water to reduce the amount of copper that is leachable to the surrounding environment. It is well established that the size of pits opening, resin canals, ray parenchyma, and ray tracheids also vary among species and may affect the uptake and penetration of micronized copper to varying degrees. This study proposes to evaluate the penetration of MCA into three pine species commonly used for outdoors applications: red pine (Pinus resinosa), Jack pine (Pinus banksiana), and Southern pine. Treatment duration and additives were used to improve the penetration of Red pine and Jack pine, while Southern pine was easily treated. Moisture content was of paramount importance in determining the degree of MCA penetration into wood, being treated for exterior applications. 11. X-Ray Diffraction as an Analytical Tool for Micronized Copper Based Preservatives Lei Wang, Michigan State University. (Pascal Kamdem) Abstract: X-ray diffraction (XRD) technique has been commonly used as a qualitative and semiquantitative analysis method in many research fields, including preservatives treated wood. This study proposes to identify micronized copper based preservatives treated wood and soluble copper based preservatives treated wood by using XRD. Micronized copper azole (MCA), micronized copper quat (MCQ) and copper azole (CA), alkaline copper quat (ACQ) with copper oxide concentration ranging from 0.25% to 1% treated southern pine have been investigated. The detection limit of copper present in wood had been discussed. A peak at around 2Θ of 31 degree is present in MCA and MCQ treated wood samples similar to peak observed in Basic copper carbonate. No peak at this degree could be observed in CA and ACQ treated wood at all copper retentions. This clearly confirms that x-ray diffraction is an effective and efficient tool for the identification of micronized copper treated wood.

6 12. Copper Migration from Micronized Copper Preservative Treated Wood in Soil Contact: Effect of Soil ph Lei Wang, Michigan State University (Pascal Kamdem, S. Dhyani) Abstract: Wood preservatives formulations made of micronized copper and organic co-biocide have been used to improve the service life of coniferous species used for exterior applications. The biological performance of such system is dependent on the amount and type of copper soluble in treated wood, which is influenced by the solubility of the source of copper in micronized system. This study proposes to estimate the amount of copper soluble and mobile in MCA (micronized copper azole) and MCQ (micronized copper quat) treated wood in soil contact by using protocol described in AWPA standard (E20-08). Treated southern pines were exposed to four types of soils with ph ranging from 4.7 to 8 for 12 weeks. About 10% of initial copper was leached from MCQ treated wood to soil with ph 4.7, 2.0% copper were leached in soil with ph 8. For MCA, 9.1% and 0.6% were leached in soil with ph 4.7 and 8, respectively. This clearly indicates that copper solubility in wood treated with micronized copper based preservatives may vary with the type and ph of soil. The other considerable observation is the high amount of copper leached from MCQ compare to MCA treated wood. It was attributed to more copper interacting with wood carboxylate-lignin in MCA compare to MCQ due to the competition between copper and quat in MCQ. 13. Leach resistance of essential oil metabolites Carol A. Clausen and Vina Wang, US Forest Service Forest Products Laboratory Abstract: Purified primary metabolites from essential oils were previously shown to be bioactive inhibitors of mold fungi in unleached southern pine sapwood, either alone or in synergy with a second metabolite. This study evaluated the leachability of these compounds after southern pine was dip-treated or vacuum impregnated. Following laboratory leaching, specimens were tested for inhibition of mold growth over 12 weeks and analyzed quantitatively by GC-MS for residual metabolite(s). Vacuum impregnating the specimens provided longer protection than dip-treating. Citronellol and carvone protected vacuum-treated specimens for the 4-wk duration of the ASTM D test, but failed to adequately protect after extending incubation to 8 weeks. Thymol completely inhibited mold growth for 12 wk in both dip-treated and vacuum impregnated specimens.

7 14. Metal and Fastener Corrosion in Treated Wood from an Electrochemical -Thermodynamic Standpoint Mike H. Freeman, Independent Wood Scientist and Paul Kovacs, SynergEthics Abstract: Since the loss of Chromated Copper Arsenate for use in residential treated wood applications, many new wood preservative systems have been successfully used and launched. One of these systems, Alkaline Copper Quanternaries showed significant corrosion in some situations. Conversion of the non-copper Co-Biocidal compound from Chloride to a Bicarbonate/Carbonate counter ion significantly helped mitigate corrosion to fasteners and metals in contact with this treated wood. To date, no one has investigated the underlying thermodynamic driving forces and steady state equilibrium conditions of these complex electrochemical systems based on comprehensive theoretical and experimental considerations. This paper introduces these complex concepts using simplified Pourbaix Diagrams and Models and further introduces a new, never before revealed equation which we call the Kovacs- Freeman Equation and Model to explain these complex phenomena in simple terms.

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