Brief Summary of Minutes of Annual Meeting

Objective 1: To Develop Novel Biobased Polymeric Materials (NE, GA, TX, WI, MT, NY and CA 1. Biodegradable Green Composites Corrugated composites were developed by Cornell University scientist using starch based emulsion-type biodegradable resin and newspaper print. While starch is plant-based and fully renewable, newspaper print is also produced mainly from wood pulp. Once used for just one day, much of the newspaper is collected but not used effectively. These composites can be used in many applications as they have excellent mechanical properties. Thus the composites provide a high-value-added outlet for this agricultural waste. The entire composites can be composted after their intended life to create organic soil. They can replace the current composites made using petroleum based resins. In another example, Cornell fabricated soy protein based composites that were reinforced using jute fabrics. In some cases the resin properties were enhanced using halloysite nanotubes (HNT). The composites were characterized for their fire performance. Jute fibers can readily catch fire and burn easily. However, the soy protein based resin does not support burning. As a result, the composites showed excellent fire resistance. At present several toxic chemicals are used to improve fire resistance of composites. The composites developed in this study were inherently fire resistant. Addition of HNT also was seen to improve the fire performance of the composites. These green composites would be suitable for housing and interior furnishings. 2. Advanced Green Composites Most green composites made using natural fibers such as jute, kenaf, etc., have moderate strength and stiffness similar to wood and wood-based products such as plywood, particle board or medium density fiber boards. They can be used as replacement of wood in many applications. Our efforts were to make very strong and tough composites that may replace aramid fiber (e.g. Kevlar) based composites that are used for ballistic protections. We utilized liquid crystalline cellulose fibers which have strength in the range of about 1600 MPa and fracture strain between 5-10%. In the present case the fibers were treated with KOH solution to improve their mechanical properties. Treated fibers were used to fabricate unidirectional composites using soy protein based resin. The KOH treatment increased the fiber strength significantly. This improved strength was also transferred to the composite properties. With 65% fiber volume, it should be possible to obtain composite strength of over 1 GPa, making them truly advanced green composites. Their toughness was also high and can replace composites currently used in ballistic applications. 3. Fibers and Thermoplastics from Agricultural Byproducts Nebraska has worked on developing fibers and thermoplastics from agricultural byproducts and co-products for textiles, composites and medical applications. This year, they have developed thermoplastic films from peanut meals, chicken feathers, and acetylated rice straws for potential uses in composites, films, and other materials. They initiated an approach of using proteins and distillers grains as textile sizes to substitute PVA and other petrobased nonbiodegradable sizing materials. They collaborated with Chinese scientists and developed high modulus silicates enhanced PLA films. They also characterized some unusual natural silk fibers produced by insects in the United States for potential textile and medical applications. 4. Nanocellulose from Biomass Fibrous materials are intrinsically high specific surface. Coupled with many uniquely attractive engineering properties, fibers are excellent and versatile templates for surface active applications. Miniaturizying fiber dimensions further expand advantages. Nanocellulose derived by chemical and mechanical defibrillation of pure cellulose isolated from various biomass can be assembled into fibrous and porous network as ultra-high specific surface templates. Electrospinning coupled with chemical modification approaches have also generated nanofiber templates for the development of highly sensitive and efficient absorbents and sensors. Polyacrylonitrile (PAN) nanofibers were prepared by Uiversity of California Davis using electrospinning, they were then modified with hydroxylamine to synthesize amidoxime polyacrylonitrile (AOPAN) chelating nanofibers as cationic absorbents. Chemical reaction can be tuned to varied degrees of nitrile conversion into amidoxime groups while retain surface topography. The adsorption abilities of Cu2+ and Fe3+ ions onto the AOPAN nanofiber mats were improved to reach maximal adsorption capacities of 215.18 and 221.37 mg/g, respectively, both fitting the Langmuir isotherm. A highly sensitive coating comprising 3-mercaptopropionic acid (MPA) monolayer modified electrospun polystyrene (PS) membranes was also constructed by sputter coating with gold, then, modified with self-assembled monolayer of MPA. The optimal PS-MPA sensors showed fast response (2-3 s) to Cu2+ at a 100 ppb detection limit. The sensor responses were reproducible toward Cu2+ in the 100 ppb-5 ppm concentration range, whereas the responses showed good linearity in the 100 ppb to 1 ppm concentration range. The sensor response to Cu2+ was low at pH 2 but increased rapidly reaching the maximum value at pH 7. Moreover, the sensors also exhibited chelation selectivity for other transition metal ions in the descending order Cu2+>Ni2+>Zn2+>Fe2+ at 1 to 5 ppm concentrations. 5. Nonwoven Composite In the natural fiber nonwoven composite research, continuous efforts were made for the determination of thermal press conditions that could result in better mechanical, acoustical, and thermal properties for kenaf/PP nonwoven composite. Compression molding temperature, time, and pressure were studied by Texas researchers. The composite tensile modulus, shear modulus, bending modulus, and impact strength were measured. The kenaf/PP composite linearity of stress-strain relationship was evaluated using finite element method (FEM). Notch effect on the composite tensile strength was assessed using open-hole (OHT) and filled-hole (FHT) testing methods. Kenaf and PP fiber thermal decomposition was evaluated using TGA. The kenaf/PP composite dynamic mechanical behavior was tested using DMA. Noise absorption and noise insulation of the kenaf/PP composite were measured using the B&K acoustical instrument. The research revealed that temperature and time were most significant processing factors. Higher heating temperature and loner press time could obtain a stiffer and stronger kenaf/PP composite. In contrast, lower heating temperature and shorter press time would produce layered bonding structure with lower rigidities, higher impact strength, and higher noise absorption and insulation. The kenaf/PP composite was more thermally stable than virgin PP plastic. The notch effect study indicated that the kenaf/PP composite is relatively insensitive to notch effect, showing a ducktile-like behavior for stress concentration. In the case of pin-filled holes, hole-width ratio was a critical factor to determine tensile strength. 6. Plasma Treatment of Ramie Fibers for Composites with polypropylene Composite and nanocomposite materials request higher adhesion even between incompatible materials. Plasma assisted processes can modify fiber surface with better adhesion and compatibility of materials. Wisconsin and Donghua University of China worked together on this research. Ramie fibers for composites with polypropylene were modified by atmospheric pressure dielectric barrier discharge plasma in alcohol-vapors environment using a design of experiments for plasma treatment parameters (flow rate, current and treatment time), in order to increase the surface hydrophobicity, adhesion and compatibility. The preliminary results are promising and work on this area will continue. Objective 2: To Develop and Evaluate Biobased Fibrous Products for Eco-friendly Crop Protection (TN, WA, NY, WI and MT) 1. biodegradable agricultural mulches Advancing the development of robust biodegradable agricultural mulches is important to alleviate concerns about the long-term environmental impact of debris formed during weathering of conventional polyethylene-based mulches. The effect of simulated weathering on the physico-chemical properties and biodegradability of fully biobased “biodegradable” mulches prepared using spun-melt and meltblown nonwovens technology from polylactic acid (PLA) and PLA-polyhydroxy alkanolate (PHA) blends has thus been investigated by Tennessee. Simulated weathering greatly affected the physico-chemical properties of the meltblown (MB) mulches, particularly for a PLA-PHA 75/25 w/w blend, which underwent a 95% loss of tensile strength and 32% decrease of molecular weight, accompanied by breakage of microfibers, during a 21 day weatherometry cycle. Tenessee researcher found that weathering increased the biodegradation of the MB-PLA+PHA mulch, with the time course of biodegradation and final extent of biodegradation (91% in 90 days) nearly matching the value obtained for the cellulosic positive control. Fourier transform infrared spectroscopy suggested the mulches underwent chain scission via a Norrish II reaction as a result of photodegradation. Spunbond (SB) mulches prepared from 100% PLA did not undergo significant physico-chemical changes, although white-colored mulch underwent a slight decrease of tensile strength compared to black-colored mulch, due to the enhancement of photodegradation by white coloring. The weathered SB mulches achieved > 69% biodegradation in 90 days, thereby meeting the inherent biodegradability requirement of the ASTM D6400 compostability standard. The nonwovens processing employed for preparing the mulches had a significant influence on their degradation. Thus, SB nonwovens may be useful as biobased and compostable materials for multi-season mulching, and other long-term agricultural applications, such as for row covers in perennial cropping systems. A manuscript for publication is in the final stages of preparation, and will be submitted soon. Tennessee, have investigated the effect of several environmental factors and soil amendments on the biodegradation of PLA and PLA-PHA nonwovens mulches through soil burial studies conducted in a greenhouse for a 30 week period. Similar to its weathering resistance discussed above, SB mulches are recalcitrant to biodegradation under ambient soil conditions. However, the MB mulches, particularly those formed from PLA-PHA blends, are biodegradable (on par with a commercial biodegradable mulch that was tested side-by-side), observed from the loss of tensile strength, molecular weight, glass transition temperature (via differential scanning calorimetry), and microfiber breakage (scanning electron microscopy). Moreover, PHA was found to decrease the extent of crystallinity for PLA. An increase of temperature (3oC above ambient), watering rate, and the addition of a carbon source for soil microorganisms moderately enhanced biodegradation, and the addition of compost more significantly increased the extent of biodegradation. FTIR analysis indicated the depolymerization occurred via hydrolysis. A soil burial study that compared sterilized versus unsterilized soil demonstrated that the loss of tensile strength occurred only in the unsterilized soil, suggesting that biodegradation, not abiotic depolymerization, occurred. A manuscript draft on this work is in its final stages of development, and will be submitted soon. More recent work suggests the decrease of tensile strength for MB mulches occurs more rapidly during an initial 3 week period, then more slowly in a first-order kinetic process thereafter, spanning several weeks. Therefore, based on the findings obtained thus far, SB nonwovens appear to be suitable materials for long-term agricultural applications, such as landscape fabrics and row covers, due to the recalcitrance toward weathering and their high mechanical strength. Since the materials are biobased and fulfill the biodegradability requirements for the compostability standard ASTM D6400, they are more sustainable than currently used products. The MB-PLA+PHA nonwovens materials are potentially valuable materials for mulching, due to their biodegradability and high tensile strength. Funding from the EPA P3 program is being used to support a student team that is testing the performance of several different inexpensive amendments (e.g., mushroom compost and switchgrass biochar) that can be applied to the mulches at the end of their service life, to help “open up” their structure, to enhance biodegradation when the mulches are subsequently plowed into the soil. Preliminary results suggest the two above-named amendments are effective. Research is ongoing. Objective 3: To develop and evaluate biobased products for health and safety applications (NE, WI, TN, WA, CA, MT and NY) 1. PLA as biomaterials for medical applications Nebraska has worked on developing and evaluating proteins and PLA as biomaterials for medical applications. This year, they have developed water stable collagen nanofibers as tissue engineering scaffolds, and developed a new method for electrospinning 3 dimensionally randomly oriented submicron fibers for medical applications. Based on the efforts mainly from Tasks 1 and 2, NE organized a symposium for the CELL-Division (Division of Cellulose and Renewable Materials) titled ‘Light-Weight Materials from Biopolymers’ at the 246th American Chemical Society National Meeting, Indianapolis, IN, September 8-12, 2013. The symposium had 16 presentations in two sessions (morning-8 papers; afternoon-8papers on September 9, 2013. 2. Antimicrobial Cellulose Fiber and Film A new method of producing antimicrobial cellulose fiber and film materials was developed by Texas researchers using an ionic liquid solvent and silver nanoparticle. Cellulose from biomass (wood, bagasse, cotton) was dissolved in an ionic liquid solvent with controlled temperature and vacuum pressure, after the solvent was pre-dispersed with nanosivler. Regenerated cellulose/nanosilver fiber and film was produced by feeding the cellulose/nanosilver solution into a lab-scale solvent spinning line. The produced cellulose/nanoparticle fiber and film materials were characterized in terms of their molecular structure (degree of crystallinity, crystal size, and crystal orientation), micro morphological structure, nanoparticle distribution, tensile strength, and thermal stability. Their bioactive efficacy was tested in accordance with the standard method of ASTM E 2149-10. The research concluded that the cellulose/nanosilver fiber was bioactive and able to kill E. coli almost completely without leaching problem. The addition of nanosilver resulted in a significant increase of the cellulose fiber tensile strength and modulus, an insignificant reduction of fiber elongation, and a slower thermal decomposition rate. Objective 4: To develop and evaluate methods to remove dyes and finishing chemicals from textile waste water (WI, GA, NE, CA and MT) 1. Modelling Dye Degradation in Textile Wastewater Wisconsin has continued work on an empirical model using only bijective functions and has tried to design a method to describe dye degradation of Reactive Blue 19, Reactive Black 9 and Reactive Red 120. The empirical model is to compare a theoretical predictive exponential decay model based on the principles of Fick’s first law of diffusion. The preliminary model is promising and Wisconsin will continue working on this research. 2. Textile wastewater treatment with Nano-particles Nebraska has developed biodegradable hollow nano-particles from zein and has demonstrated that these particles have extremely high sorption capacity to dyes and could be used for dye removal from wastewater. Impact Our work on utilizing agricultural byproducts and co-products for textile, composite and medical applications provide potential opportunities for value addition to Nebraska’s and the United States agriculture , assist in reducing cost of biofuels and has the potential to develop a new biobased industry that will create jobs and benefit the economy. Substituting PVA that is widely used for sizing with biodegradable proteins and distillers dried grains will substantially reduce the pollution from the textile industry. Similarly, using nanoparticles to absorb dyes in waste water will help reduce pollution from the textile industry. Our approach of using inexpensive agricultural bypoducts and coproducts available in the United States for textile applications will provide a distinct advantage for the textile industry in the United States to be sustainable, environmentally friendly and competitive compared to the developing countries where such agricultural materials are not available in large quantities and/or low costs. Our invention on developing 3D scaffolds from proteins provides unique biomaterials for tissue engineering and other medical applications. These biomaterials are shown to be biocompatible, easy to be manufactured and can be tailored for specific needs and could therefore lead to novel treatments for various diseases and also lower medical costs. The symposium NE organized for the 246th American Chemical Society National Meeting attracted researchers around the world who discussed the science and industrial applications of biopolymers for textiles, composites and medical applications. Our students, both graduate and undergraduate (two PhD, one MS and one undergraduate), gave oral presentations of their researches at the symposium and gained valuable experiences in presenting and sharing their knowledge to experts in their fields This research directly relates to the nation’s efforts in utilizing biomass from agricultural crops and residues for producing high-performance renewable and biodegradable materials. Use of green composites would support the Government’s ‘Bio-preferred’ program. Although the liquid crystalline cellulose fibers were not produced in our labs, the technology is being developed in the US. For example, within this program, medium strength cellulose fibers which can be used in textile applications have already been made. With increased molecular orientation and higher crystallinity, properties of these fibers can be increased significantly and made suitable for high strength applications including composites. The advanced green composites may also be used in military applications.mm PLA-based spunbond nonwovens are potentially valuable materials for long-term agriculture, such as row covers and landscape fabrics, due to their recalcitrance toward weathering, high mechanical strength, and their sustainability: fully biobased and compostable. MB nonwovens prepared from PLA-PHA blends are potentially valuable biodegradable agricultural mulches, and may be particularly useful for multi-season use or for long growing seasons, and for organic agriculture, due to their high rate and extent of biodegradation (particularly after being weathered), their high mechanical strength, and their formation from 100% biobased polymers. This research also addresses the nation’s biomass research priority by utilizing agricultural crops and residues for producing high-performance renewable and biodegradable cellulose fiber and film materials. The pure cellulose and cellulose/nanoparticle fiber/film produced with this new method can be used for diverse textile and apparel applications to compete with Rayon and Tencel/Lyocell fibers. Furthermore, the new cellulose fibers can also be used for high-end applications in other industrial sectors including carbon fiber manufacture, personal care, health care, and military applications. Use of natural fiber nonwovens for making fiber composites continues to be one of the biobased polymer material mainstreams in competing with plastics and foams in auto interior applications. The one-step process technology of producing bast fiber auto interior composites will provide two critical industrial values: to increase vehicle fuel efficiency by reducing vehicle weight; and to improve vehicle recyclability.

Ma, H., Xu, R., Xu, H., Zhang, L. Zhong, Y. Jiang, Q., Yang, Y., and Mao*, Z. High Modulus Silicates/Poly (L-Lactic Acid) Based Polymers Assemblies for Potential Applications in Tissue Engineering. Functional Materials Letters. 6(4) 1350037(5 pages) (2013). Yang, Y. and Reddy*, N., Potential of using plant proteins and chicken feathers for cotton warp sizing. Cellulose. 20(4), 2163-2174(2013). Chen, L., Reddy, N., and Yang*, Y. Soyproteins as Environmentally Friendly Sizing Agents to Replace Poly(vinyl alcohol). Environmental Science and Pollution Research. 20(9), 6085-6095 (2013). Reddy, N., and Yang*, Y. Thermoplastic Films from Plant Proteins. Journal of Applied Polymer Science. 130(2), 729-738(2013). Yang, Y. and Reddy*, N., Utilizing Discarded Plastic Bags as Matrix Material for Composites Reinforced with Chicken Feathers. Journal of Applied Polymer Science. 130(1) 307-312(2013). Reddy, N., Jiang, Q., Jin, E., Shi, Z., Hou, X., and Yang*, Y. Bio-Thermoplastics from Grafted Chicken Feathers for Potential Biomedical Applications. Colloids and Surfaces B: Biointerfaces. 110, 51-58(2013). Zhang, G., Huang K., Jiang, X., Huang*, D, and Yang, Y. Acetylation of rice straw for thermoplastic applications. Carbohydrate Polymers. 96(1),218-226(2013). Xu, H., Zhang, Y., Jiang, Q., Reddy, N., and Yang*, Y. Biodegradable Hollow Zein Nanoparticles for Removal of Reactive Dyes from Wastewater. Journal of Environmental Management. 125, 33-40(2013). Chen, L., Reddy, N., and Yang*, Y. Remediation of Environmental Pollution by Substituting Poly(vinyl alcohol) with Biodegradable Warp Size from Wheat Gluten. Environmental Science & Technology. 47(9) 4505-4511(2013). Reddy, N., Jiang, Q., and Yang*, Y. Properties and Potential Medical Applications of Silk Fibers Produced by Rothischildia lebeau. Journal of Biomaterials Science: Polymer Edition. 24(7) 820-830(2013). Huang, F., Y. Xu, S. Liao, D. Yang, Y.-L. Hsieh and Q. Wei, Preparation of amidoxime polyacrylonitrile chelating nanofibers and their application for adsorption of metal ions, Materials 2013, 6(3): 969-980. Hsieh, Y.-L. Cellulose Nanocrystals and Self-Assembled Nanostructures from Cotton, Rice Straw and Grape Skin: A Source Perspective, Journal of Materials Science, 48(22): 7837-7846 (2013). Sathiskumar Dharmalingam, Biodegradation and Photodegradation of PLA and PLA-blend-PHA Nonwovens Agricultural Mulches in Real Soil Conditions, PhD Dissertation, University of Tennessee,, 12/13 A.T. Corbin, C. Miles, J. Cowan, D.G. Hayes, J. Moore-Kucera, D.A. Inglis, 2013, biodegradable plastic mulch in certified organic production systems, [Online]. eXtension Foundation, eOrganic Community of Practice. Available at: http://www.extension.org/pages/67951 (verified 02 May 2013). Elodie Hablot, Satiskumar Dharmalingam, Douglas G. Hayes, Larry C. Wadsworth, Christopher Blazy, Ramani Narayan, and Debra A. Inglis, 2013, Effect of simulated weathering on physico-chemical properties and inherent biodegradation of PLA/PHA non-woven-based agricultural mulches, manuscript in preparation (will be submitted within next 3-4 wk) Larry C. Wadsworth, Douglas G. Hayes, Annette L. Wszelaki, Tommy L. Washington, Jeffery Martin, Jaehoon Lee, Robert Raley, C. Tyler Pannell, Sathishkumar Dharmalingam, Carol Miles, Debra A. Inglis, and Arnold M. Saxton, 2012, Evaluation of Biodegradable Spun-Melt 100% Polylactic Acid Nonwovens Mulch Materials in a Greenhouse Environment, Journal of Engineered Fibers and Fabrics in press. 8 (4) 50-59. (Note: this manuscript was submitted in 2011, a long time ago, but was finally published this year.) Corbin, A., Cowan, J. Miles, C, Hayes, D.G., Dorgan, J., Inglis D.A. 2013. Using Biodegradable Plastics as Agricultural Mulches, Washington State University Extension Factsheet FS103E, published 01/13 Edwards, V., B Condon, P Sawhney, M Reynolds, C Allen, S Nam, A Bopp, J Chen and N Prevost, Electrokinetic analysis of hydroentangled greige cotton-synthetic fiber blends for absorbent technologies, Textile Research Journal, 2013, 83(18), 1950–1960. Hao, A., Zhao, H., and Chen, J.Y. Kenaf/Polypropylene Nonwoven Composites: the Influence of Manufacturing Conditions on Mechanical, Thermal, and Acoustical Performance. Composites Part B: Engineering, 2013, 54(11), 44–51. Hao, A., Zhao, H., Jiang, Wei, and Chen, J.Y. Mechanical Properties of Kenaf/Polypropylene Nonwoven Composites. Journal of Polymers and the Environment, 2012, 20(4), 959?966. Patent: Li, Y. B., W. Stephens, M. Tusim, X. Luo “Production of polyols and polyurethanes”. Filed on June 21, 2012. Application No. 13/530,056 Presentations at Peer reviewed International Conference Xu, H., Reddy, N., and Yang, Y. Potential of PEGylated zein nanoparticles for biomedical applications: In vitro and in vivo studies. 246th ACS National Meeting & Exposition, Indianapolis, IN, United States, September 8-12, 2013 (2013), CELL-16. Hou, X., Yan, D., Sun, F., Cheng, Y., and Yang, Y. Effect of pre-treatment for cotton stalk bark on mechanical properties of lightweight polypropylene composites. 246th ACS National Meeting & Exposition, Indianapolis, IN, United States, September 8-12, 2013 (2013), CELL-19. Shen, L., Xu, H. and Yang, Y., Quantitative analysis of reaction between gliadin and citric acid under weak acidic and weak alkaline conditions. 246th ACS National Meeting & Exposition, Indianapolis, IN, United States, September 8-12, 2013 (2013), CELL-20. Jiang, J., Reddy, N., and Yang, Y., Biocomposites developed using poultry feathers as matrix and reinforcement. 246th ACS National Meeting & Exposition, Indianapolis, IN, United States, September 8-12, 2013 (2013), CELL-21. Xu, H., and Yang, Y., Novel regenerated protein fibers from chicken feather keratin. 246th ACS National Meeting & Exposition, Indianapolis, IN, United States, September 8-12, 2013 (2013), CELL-23. Jiang, J., Xu, H., and Yang, Y., Water-stable 3D soyprotein scaffolds for soft tissue regeneration. 246th ACS National Meeting & Exposition, Indianapolis, IN, United States, September 8-12, 2013 (2013), CELL-24. Huang, Y., Xu, H., and Yang, Y., Potential of 3D porous scaffolds from feather keratin for cartilage repair. 246th ACS National Meeting & Exposition, Indianapolis, IN, United States, September 8-12, 2013 (2013), CELL-27. Temme, L., Reddy, N., Shi, Z., and Yang, Y., Properties and potential applications of components extracted from sorghum distillers dried grains. 246th ACS National Meeting & Exposition, Indianapolis, IN, United States, September 8-12, 2013 (2013), CELL-28. Pan, G., Hou, X., and Yang, Y., Preparation and mechanical properties of poly(lactic acid)/wheat straw fibers composites. 246th ACS National Meeting & Exposition, Indianapolis, IN, United States, September 8-12, 2013 (2013), CELL-29