Department of Sustainable Biomaterials

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https://hdl.handle.net/10919/23939

The Department of Sustainable Biomaterials was formerly the Department of Wood Science and Forest Products. The name was changed in 2012.

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2011 Annual Report, Center for Forest Products Business
(Virginia Tech. Department of Wood Science and Forest Products, 2011-08)
This annual report details student and faculty accomplishments for the Center in 2010-2011.
3D printing of lignin: Challenges, opportunities and roads onward
Ebers, L. -S.; Arya, Aditi; Bowland, C. C.; Glasser, Wolfgang G.; Chmely, S. C.; Naskar, A. K.; Laborie, Marie-Pierre Genevieve (2021-06)
As the second most abundant biopolymer on earth, and as a resource recently becoming more available in separated and purified form on an industrial scale due to the development of new isolation technologies, lignin has a key role to play in transitioning our material industry towards sustainability. Additive manufacturing (AM), the most efficient-material processing technology to date, has likewise made great strides to promote sustainable industrial solutions to our needs in engineered products. Bringing lignin research to AM has prompted the emergence of the nascent "lignin 3D printing" field. This review presents the recent state of art of this promising field and highlights its challenges and opportunities. Following a review of the industrial availability, molecular attributes, and associated properties of technical lignins, we review R&D efforts at implementing lignin systems in extrusion-based and stereolithography (SLA) printing technologies. Doing so underlines the adage of lignin research that "all lignins are not created equal," and stresses the opportunity nested in this chemical diversity created mostly by differences in isolation conditions to molecularly select and tune the attributes of technical lignin systems towards desirable properties, be it by modification or polymer blending. Considering the AM design process in its entirety, we finally propose onward routes to bring the full potential to this emerging field. We hope that this review can help promote the unique value and overdue industrial role of lignin in sustainable engineered materials and products.
Amorphous solid dispersions of enzalutamide and novel polysaccharide derivatives: investigation of relationships between polymer structure and performance
Wilson, Venecia R.; Lou, Xiaochun; Osterling, Donald J.; Stolarik, DeAnne F.; Jenkins, Gary J.; Nichols, Brittany L. B.; Dong, Yifan; Edgar, Kevin J.; Zhang, Geoff G. Z.; Taylor, Lynne S. (Nature Research, 2020-10-28)
Amorphous solid dispersion (ASD) is a widely employed formulation technique for drugs with poor aqueous solubility. Polymers are integral components of ASDs, but mechanisms by which polymers lead to the generation and maintenance of supersaturated solutions, which enhance oral absorption in vivo, are poorly understood. Herein, a diverse group of newly synthesized cellulose derivatives was evaluated for their ability to inhibit crystallization of enzalutamide, a poorly soluble compound used to treat prostate cancer. ASDs were prepared from selected polymers, specifically a somewhat hydrophobic polymer that was extremely effective at inhibiting drug crystallization, and a less effective, but more hydrophilic, crystallization inhibitor, that might afford better release. Drug membrane transport rate was evaluated in vitro and compared to in vivo performance, following oral dosing in rats. Good correlation was noted between the in vitro diffusion cell studies and the in vivo data. The ASD formulated with the less effective crystallization inhibitor outperformed the ASD prepared with the highly effective crystallization inhibitor in terms of the amount and rate of drug absorbed in vivo. This study provides valuable insight into key factors impacting oral absorption from enabling ASD formulations, and how best to evaluate such formulations using in vitro approaches.
Amphiphilic hydroxyalkyl cellulose derivatives for amorphous solid dispersion prepared by olefin cross-metathesis
Dong, Yifan; Mosquera-Giraldo, Laura I.; Troutman, Jacob; Skogstad, Brittny; Taylor, Lynne S.; Edgar, Kevin J. (Royal Society of Chemistry, 2016-07-07)
Olefin cross-metathesis (CM) has enabled design and synthesis of diverse, amphiphilic cellulose ether derivatives (e.g. of ethyl and methyl cellulose). In this paper, hydroxyalkyl cellulose was selected as a hydrophilic starting material, with the additional advantage that it has DS (OH) 3.0 that allows targeting of a full range of DS of selected functional groups. Hydroxypropyl cellulose (HPC) was first etherified with 5-bromopent-1-ene to attach olefin “handles” for metathesis, whereby control of molar ratios of sodium hydride and 5-bromopent-1-ene permits full DS control of appended olefin. These olefin-terminated HPC ethers then were subjected to CM with acrylic acid and different acrylates, followed by diimide hydrogenation to reduce the resulting α,β-unsaturation. NMR and FT-IR spectroscopies were useful tools for following reaction progress. One of the product carboxyl-functionalized HPC derivatives, designated HPC-Pen106-AA-H, showed high promise as a crystallization inhibitor of the antiviral drug telaprevir. Its nucleation-induction inhibitory ability was compared to those of commercial controls, HPC and HPMCAS. All three polymers were very effective for inhibiting telaprevir crystallization, increasing induction time up to 8-fold. HPC did not effectively prevent amorphous particle growth, whereas the carboxyl-containing HPC-Pen106-AA-H and HPMCAS were able to prevent formation of agglomerates of amorphous drugs.
Analysis of electricity consumption: a study in the wood products industry
Quesada, Henry Jose; Wiedenbeck, Janice K.; Bond, Brian H. (2016-10)
This paper evaluates the effect of industry segment, year, and US region on electricity consumption per employee, per dollar sales, and per square foot of plant area for wood products industries. Data was extracted from the Industrial Assessment Center (IAC) database and imported into MS Excel. The extracted dataset was examined for outliers and abnormalities with outliers outside the quantile range 0.5-99.5 dropped from the analysis. A logarithmic transformation was applied to eliminate the skewness of the original data distributions. Correlation measurements indicated a moderate association between the response variables; therefore, a multivariate analysis of variance test was performed to measure the impact of the three factors: industry type, year, and region, simultaneously on all response variables. The results indicated some effect associated with all three factors on the three measures of electricity consumption. Subsequently, univariate ANOVA tests were conducted to determine the levels of the factors that were different. Most levels of industry type were associated with significantly different energy consumption, an expected result since some of the industries are more energy intensive than others. The industries in Standard Industry Code (SIC) 2493 (reconstituted wood products) are the groups with the highest electricity consumption with means of 38,096.28 kWh/employee, 0.86 kWh/sales, and 154.14 kWh/plant area while industries grouped in SIC 2451 (mobile homes) have the smallest consumption with means of 6811.01 kWh/employee, 0.05 kWh/sales, and 9.45 kWh/plant area. Interestingly, differences in regional consumption were found to be linked to the proportion of industry types by region. Data analysis also indicated differences in electricity consumption per employee for the factor year, but for the other response variables, no differences were found. These main results indicate that industries in the wood products sector have different electricity consumption rates depending on the type of manufacturing processes they use. Therefore, industries in this sector can use these comparisons and metrics to benchmark their electricity consumption as well to understand better how electricity costs might vary depending on the region they are located.
Annual Report, Center for Forest Products Business 2019
(2019-08-24)
This annual report lists faculty and student accomplishments at the Center for the period of July 1, 2018 - June 30, 2019.
Annual Report: Center for Forest Products Business, 2013-2014
(Virginia Tech, 2014)
This annual report details student and faculty accomplishments for the Center in 2013-2014.
Annual Report: Center for Forest Products Business, 2017-2018
(Virginia Tech, 2018)
This annual report details student and faculty accomplishments for the Center in 2017-2018.
Annual Report: Center for Forest Products Business, August 2016
(Virginia Tech, 2016-08)
This annual report lists faculty and student accomplishments at the Center for the period of July 1, 2015 - June 30, 2016.
Barriers, enablers and market governance: A review of the policy landscape for repair of consumer electronics in the EU and the U.S.
Svensson-Hoglund, Sahra; Richter, Jessika Luth; Maitre-Ekern, Eleonore; Russell, Jennifer D.; Pihlajarinne, Taina; Dalhammar, Carl (2021-03-15)
Many strategies have been proposed to support the transition to a Circular Economy (CE). In most cases, circular design and product life-extension practices specify repair as an essential element. In both the EU and the U.S., policymakers are attempting to increase the amount of repairs made, through the introduction of recent EU Ecodesign regulation changes and proposed US Right to Repair legislation. This review explores the current policy landscape for repair services by first outlining legal and market barriers to stakeholder participation in repair activities, and which stakeholders are affected. The review reveals a wide range of fundamental obstacles to both supply and demand of repair, including Intellectual Property, Consumer, Contract, Tax and Chemical laws, along with issues of design, consumer perceptions and markets. Subsequently, the current and proposed policy solutions to address barriers and increase repair activities are reviewed. A comparative assessment of the EU and the U.S. is followed by a discussion on the current repair market governance structure, which is found to be primarily centralized (i.e. repair services concentrated with manufacturers), with possible implications for upscaling repair. New policy proposals challenge this governance. Introducing the concept of a Repair Society Framework as a market transformation tool, we comprehensively discuss the current state of repair and provide an outlook for research and policy in this area. (C) 2020 The Authors. Published by Elsevier Ltd.
Benchmarking Performance Measurement and the Implementation of Lean Manufacturing in the Secondary Wood Processing Rough Mill
Cumbo, Dan; Kline, D. Earl; Van Aken, Eileen M.; Smith, Robert L. (Virginia Tech, 2004-09)
It is hypothesized that, while other components of the secondary wood products value stream; e.g., moulding, turning, sanding, etc, are being integrated and “leaned up” so to speak, the rough mill represents a real or perceived barrier to full implementation of lean manufacturing tools, techniques and concepts. This study investigated the implementation of lean manufacturing in the rough mill as well as performance measurement and metrics at both the rough mill and overall business level. Data were collected from a nationwide survey of secondary wood processing facilities.
Bioactive Cellulose Nanocrystal-Poly(epsilon-Caprolactone) Nanocomposites for Bone Tissue Engineering Applications
Hong, Jung Ki; Cooke, Shelley L.; Whittington, Abby R.; Roman, Maren (2021-02-25)
3D-printed bone scaffolds hold great promise for the individualized treatment of critical-size bone defects. Among the resorbable polymers available for use as 3D-printable scaffold materials, poly(epsilon-caprolactone) (PCL) has many benefits. However, its relatively low stiffness and lack of bioactivity limit its use in load-bearing bone scaffolds. This study tests the hypothesis that surface-oxidized cellulose nanocrystals (SO-CNCs), decorated with carboxyl groups, can act as multi-functional scaffold additives that (1) improve the mechanical properties of PCL and (2) induce biomineral formation upon PCL resorption. To this end, an in vitro biomineralization study was performed to assess the ability of SO-CNCs to induce the formation of calcium phosphate minerals. In addition, PCL nanocomposites containing different amounts of SO-CNCs (1, 2, 3, 5, and 10 wt%) were prepared using melt compounding extrusion and characterized in terms of Young's modulus, ultimate tensile strength, crystallinity, thermal transitions, and water contact angle. Neither sulfuric acid-hydrolyzed CNCs (SH-CNCs) nor SO-CNCs were toxic to MC3T3 preosteoblasts during a 24 h exposure at concentrations ranging from 0.25 to 3.0 mg/mL. SO-CNCs were more effective at inducing mineral formation than SH-CNCs in simulated body fluid (1x). An SO-CNC content of 10 wt% in the PCL matrix caused a more than 2-fold increase in Young's modulus (stiffness) and a more than 60% increase in ultimate tensile strength. The matrix glass transition and melting temperatures were not affected by the SO-CNCs but the crystallization temperature increased by about 5.5 degrees C upon addition of 10 wt% SO-CNCs, the matrix crystallinity decreased from about 43 to about 40%, and the water contact angle decreased from 87 to 82.6 degrees. The abilities of SO-CNCs to induce calcium phosphate mineral formation and increase the Young's modulus of PCL render them attractive for applications as multi-functional nanoscale additives in PCL-based bone scaffolds.
A Case Study to Determine Drivers and Barriers of Appalachian Forest Products in Central America
Quesada, Henry Jose; Lyon, Scott; Smith, Robert (Instituto Tecnologico De Costa Rica, 2012-06-04)
The purpose of this research was to determine drivers and barriers of Appalachian wood product competitors in Central America. Potential market opportunities for Appalachian forest product companies in Central America were evaluated and strategies were developed to increase exports of Appalachian wood products to Central America. The findings support the claim that United States forest product companies have not put enough effort into marketing forest products to Central America. Forests in El Salvador, Panama, and Costa Rica are limiting harvests and the industry lacks support from the government, reducing the amount of raw material and production. Inconsistencies between Appalachian and Central American wood products industries (e.g., dimensions) act as a barrier to the efficient exchange of wood products. The best market strategies for Appalachian forest products companies to increase sales into Central America are: partner with local wholesalers, offer higher value-added products, and maintain similar pricing with competition. An outside source of wood is needed to meet the needs of growing regional infrastructure.
CELL 256: Role of dispersion and polar interactions in the adsorption of cellulases onto lignin
Roman, Maren; Jiang, Feng; Chen, Qian; Esker, Alan R. (2018-03)
Residual lignin in pretreated biomass hinders its enzymatic hydrolysis. Nonionic surfactants are known to have beneficial effects on the enzymatic hydrolysis of lignocellulosic biomass but their mechanisms of action at the molecular level are incompletely understood. This study investigates the effect of a nonionic surfactant, Tween 80, on the adsorption of cellulases onto model lignin substrates. Lignin substrates were prepared by spin coating of flat substrates with three different types of lignin: organosolv lignin, kraft lignin, and milled wood lignin. Tween 80 and cellulase adsorption onto the lignin substrates was analyzed with a quartz crystal microbalance with dissipation monitoring. Supporting experiments of Tween 80 and cellulase adsorption onto self-assembled monolayers with lignin-related functional groups provided critical insights into the role of polar and dispersive functional groups in lignin on cellulase adsorption and the effect of Tween 80 on the process.
Cellulose derivatives with a low degree of substitution
(United States Patent and Trademark Office, 1996-06-04)
The invention is directed to the formation of cellulose derivatives using homogenous phase reaction conditions. Cellulose is dissolved using DMAc/LiCl and a reagent system is added to promote the acylation of an appropriate acid anhydride or free carboxylic acid. One reagent system includes N,N-dicyclohexylcarbodiimide (DCC) and 4-pyrrolidinopyridine (PP). Another reagent system includes p-toluene sulfonyl chloride (TsCl) and pyridine (Py).
Center Focus, April 2007
(Virginia Tech, 2007-04)
The Center for Forest Products Business produces a newsletter, The Center Focus, once a calendar quarter. This newsletter details upcoming events, new members, feature articles, and other happenings at the Center.
Center Focus, December 2006
(Virginia Tech, 2006-12)
The Center for Forest Products Business produces a newsletter, The Center Focus, once a calendar quarter. This newsletter details upcoming events, new members, feature articles, and other happenings at the Center.
Center Focus, December 2007
(Virginia Tech, 2007-12)
The Center for Forest Products Business produces a newsletter, The Center Focus, once a calendar quarter. This newsletter details upcoming events, new members, feature articles, and other happenings at the Center.
Center Focus, Fall & Winter 2008
(Virginia Tech, 2008)
The Center for Forest Products Business produces a newsletter, The Center Focus, once a calendar quarter. This newsletter details upcoming events, new members, feature articles, and other happenings at the Center.
Center Focus, Fall 2009
(Virginia Tech, 2009)
The Center for Forest Products Business produces a newsletter, The Center Focus, once a calendar quarter. This newsletter details upcoming events, new members, feature articles, and other happenings at the Center.

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