Progress 11/15/06 to 11/14/11
Outputs
OUTPUTS: The objective of this proposal is to develop a unique training program to produce outstanding graduates to meet the future needs of a globally interconnected, technologically advanced, rapidly diversifying and consumer driven wood and wood based fiber industry. New wood based advanced materials have been developed and structure/chemistry/properties relationships developed. Currently, three well-trained individuals have been prepared for the research area of wood and wood-based fiber. The main output of this project was the teaching and mentoring of three excellent students, Kelley Spence, Rachel Ernest and Justin Zoppe. Both Kelley Spence and Justin Zoppe earned PhD degrees from the Forest Biomaterials Department at NCSU as planned. Rachel Ernest completed a MS degree from the Forest Biomaterials Department at NCSU; she completed a MS degree instead of a PhD degree due to significant personal issues that prevented her from continuing her training. The students earned a Graduate Research Certificate, which provided formal training in research administration, personnel management, research ethics and communication skills. Their training has developed in all three of these researchers the ability to be leaders in the area of wood and fiber engineering. Research activities for Kelley Spence included the production, characterization and analysis of microfibrillated celluloses that have applications in packaging, plastic parts, food additives, and many other uses. Justin Zoppe's research activities involved the chemical functionalization of cellulose nanocrystals, characterization and analysis of such materials that have applications as sensing devices, emulsifiers, viscosity modifiers and other applications. Rachel Ernest conducted experiments with surface modifications of microfibrillated and bacterial cellulose with acetylation and by blending with polyamide and characterized and analyzed the resulting materials, which had unique material properties. The students were involved in a great number of professional enhancement activities, including making presentations at local and international technical conferences, tutoring and mentoring undergraduate students, presenting webinars, participating in study-abroad experiences, collaborating with other departments, universities and private companies, developing a website, performing teaching activities, and others. In addition, several peer-reviewed journal articles were published as a method to distribute and disseminate research findings. The preparation of these articles was integral in the professional development of the students. PARTICIPANTS: Participants. Dr. Richard Venditti and Dr. Orlando Rojas acted as the project directors and were also student advisors. Dr. Joel Pawlak acted as a student advisor. Kelley Spence, Justin Zoppe and Rachel Ernest were Fellows supported by this project. Other participants included Aalto University as a host for a Fellow, Microfluidics Corporation as a collaborator and supplier of equipment, Mead Westvaco as a collaborator and supplier of material and equipment. Dr. Lucian Lucia, Dr. Amy Gunden, Dr. Martin Hubbe, Dr. Kirill Efimenko all served on research committees providing valuable perspectives to the research. TARGET AUDIENCES: Target Audiences. Racial and ethnic minorities were served in this project through a visit from Shaw University students to NCSU during a visitation program. Also, racial and ethnic minorities were mentored for a summer science research experience through the SEED NC program Fellows. Efforts. The Fellows participated in providing a summer science research program for several disadvantaged high school students. All of the Fellows participated as teaching assistants for undergraduate courses at NCSU. One of the Fellows wrote a laboratory manual for a process control experiment. Fellows also provided mentoring to undergraduate students performing research. Extension and outreach mainly consisted of peer reviewed articles, posters, and presentations. One Fellow did deliver a webinar on microfibrillated cellulose. The webinar was attended by 114 people spanning the world. Another Fellow spent a semester at Aalto University in the Department of Forest Products Technology in Espoo, Finland. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
This project has successfully demonstrated a more holistic method of training doctoral students that was successful. Through interactions with collaborators and other faculty, as well as from dissemination activities (webinars, seminars, presentations, web page) the methodologies have spawned similar programs, especially in the Forest Biomaterials Department at NCSU. With respect to change in knowledge, the main new knowledge is detailed in peer reviewed journals, dissertations and presentations and is briefly outlined below for each student. Justin Zoppe's findings have demonstrated a variety of synthetic pathways to modify the surface of nanocelluloses to ultimately produce novel biomaterials with advanced functionalities. The future prospects of modified nanocelluloses were demonstrated in such areas as high-strength, biodegradable nanocomposites, nanosensing, biomedical, and cosmetics applications. It is expected that these studies will provide the basis for the development of novel nanomaterials derived from abundant natural resources and bring forth new and advanced applications of cellulosic nanoparticles. Rachel Ernest's research in surface modification of highly refined cellulosic fibers, generally called microfibrillated cellulose (MFC), explained some aspects of the bonding structure of these MFC fibrils. She also created materials with new functionalities. Surface acetylation of MFC was accomplished with a heterogeneous reaction with acid anhydride and acetic acid with only heat as the catalyst. In addition, produced composites of MFC with poly (gamma-glutamic acid) developed new materials and offered an opportunity to study and understand hydrophilic modifications to the MFC films. Adding a hygroscopic polymer to the MFC surface could make the material useful in biomedical applications, such as bandages or tissue scaffolds. In Kelley Spence's research wood pulps of different chemical compositions were used to produce MFCs to investigate the effect of chemical composition on microfibril and film properties. New materials were created with different chemical compositions and structures. Insight into different processing methods to produce MFC films was also determined with respect to product final properties, economics, energy use, and processability. In addition, multi layered and composite structures of MFC base materials were produced and diffusion and water properties modeled and analyzed. Her research should further promote the utilization of MFC to reduce the amount of petroleum-based products currently used. Observations such as improved mechanical properties when utilizing the less processed, lignin-containing MFCs should advocate further research into production and utilization of these materials. Finally, the barrier properties obtained with coated MFCs should promote further research in utilizing these materials to replace polyethylene in packaging applications.
Publications
- Peresin, M. S., Habibi, Y., Zoppe, J. O., Pawlak, J. J., Rojas, O. J., (2010) Nanofiber Composites of Polyvinyl Alcohol and Cellulose Nanocrystals: Manufacture and Characterization. Biomacromolecules, 11 (3): 674-681.
- Spence, Kelley L., Venditti, Richard A., Rojas, Orlando J., Pawlak, Joel J., (2009) Wood pulp chemical composition effects on the development of microfibrillated cellulose, 237th ACS National Meeting, Salt Lake City, UT, March 22-26, 2009.
- Spence, Kelley L.; Venditti, Richard A.; Rojas, Orlando J.; Pawlak, Joel J., (2009) Water interactions for various types of microfibrillated cellulose, 237th ACS National Meeting, Salt Lake City, UT, March 22-26, 2009.
- Spence, K., Venditti, R.A., Habibi, Y., Rojas, O.J., Pawlak, J., (2010) Production of microfibrillated cellulose by various processing methods, 239th ACS National Meeting, San Francisco, CA, March 21-25, 2010.
- Spence, K., Venditti, R.A., Rojas, O.J., (2010) Aspects of Raw Materials and Processing Conditions on the Production and Utilization of Microfibrillated Cellulose, 2010 TAPPI International Conference on Nanotechnology for the Forest Product Industry, Espoo, Finland, September 27-29, 2010.
- Spence, K.L., Habibi, Y., and Dufresne, A., (2011) Nanocellulose Based Composites in Cellulose Fibers: Bio- and Nano-Polymer Composites. Kalia, S., Kaith, B., and I. Kaur (Eds). 2011. ISBN: 978-3-642-17369-1.
- Spence, K., Tucker, J., and Hart, P. (2009). Comparison of various hardwood Kraft pulp pre-bleaching techniques. TAPPI Journal. April, p 10-14.
- Spence, K., Venditti, R., Rojas, O. (2009). Sugar surfactants in paper recycling. Nordic Pulp and Paper Research Journal. 24(1): 107-111.
- Spence, K., Venditti, R., Habibi, Y., Rojas, O., and Pawlak, J. (2010). The effect of chemical composition on microfibrillar cellulose films from wood pulps, processing and physical properties. Bioresource Technology. 101: 5961-5968.
- Zoppe, J. O., Peresin, M. S., Habibi, Y., Venditti, R. A., Rojas, O. J., (2009). Reinforcing Poly(caprolactone) Nanofibers with Cellulose Nanocrystals, ACS Applied Materials & Interfaces, 1(9): 1996-2004.
- Spence, K., Venditti, R., Habibi, Y., Rojas, O., and Pawlak, J. (2010). The effect of chemical composition on microfibrillar cellulose films from wood pulps, water interactions and physical properties for packaging applications. Cellulose. 17: 835-848.
- Spence, K., Venditti, R., Habibi, Y., Rojas, O., and Pawlak, J. (2011). A comparative study of energy consumption and physical properties of microfibrillated cellulose produced by different processing methods, Kelley Spence, Richard A. Venditti, Orlando J. Rojas, Youssef Habibi, Joel. J. Pawlak, Cellulose, 18: 1097-1111.
- Spence, K., Venditti, R., Rojas, O., and Pawlak, J. (2011). Improvement of water vapor barrier properties of films produced from microfibrillated cellulose. BioResources. 6(4): p 4370-4388.
- Spence, K., Venditti, R., Rojas, O., and Pawlak, J., (2011) Effects of lignin on processing and properties of microfibrillated cellulose, ACS Natl. Meeting, March 27-31, 2011, Anaheim, CA.
- Zoppe, J., Rojas, O.J., Habibi, Y., Johansson, L-S., Osterberg, M., Laine, J., Venditti, R.A., (2010) Cellulose Nanocrystals grafted with poly(N-isopropylacrylamide) brushes via Surface-Initiated Atom Transfer Radical Polymerization (SI-ATRP), Nordic Polymer Days 2010, Helsinki May 24-26, 2010.
- Zoppe, J. O., Habibi, Y., Rojas, O. J., Venditti, R. A., Johansson, L.-S., Efimenko, K., Osterberg, M., Laine, J., (2010) Poly(N-isopropylacrylamide) Brushes Grafted from Cellulose Nanocrystals via Surface-Initiated Single-Electron Transfer Living Radical Polymerization. Biomacromolecules, 11 (10): 2683-2691.
- Zoppe, J.O., Rojas, O.J., Venditti, R.A., Osterberg, M., Laine, J. (2011) Thermo-responsive Polymer Brushes Grafted from Cellulose Nanocrystals and their Interfacial Behavior, 2011 Tappi International Conference on Nanotechnology of Renewable Materials, Arlington, VA, June 6-8, 2011.
- Zoppe, Justin, Osterberg, Monika, Venditti, Richard, Laine, Janne, Rojas, Orlando, (2011) Surface Interaction Forces of Cellulose Nanocrystals Grafted with Thermo-responsive Polymer Brushes, Biomacromolecules, 12(7): 2788-2796.
- Zoppe, J. O., Venditti, R. A., Rojas, O. J., (2012) Pickering Emulsions Stabilized by Cellulose Nanocrystals Grafted with Thermo-responsive Polymer Brushes. Journal of Colloid & Interface Science, 369: 202-209.
- Ernest, R., Pawlak, J. J., Grunden, A., Devine, A. A., (2009) Biological Cellulosic Micro Composite Materials, Annual Meeting of the American Chemical Society Salt Lake City, Utah.
- Ernest, R., Pawlak, J.J., (2010) Micro-fibrillated Cellulose and Bacterial Polyamide, Annual Meeting of the American Chemical Society 2010 San Francisco, CA.
- Pawlak, J. J., Venditti, R. A., Lee, S. Y., Yuan, L., Ernest, R., (2010) Fibrillated cellulose composite materials, 2010 Progress in Paper Physics Conference in Montreal, QC.
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Progress 11/15/09 to 11/14/10
Outputs
All three students (Kelley Spence, Rachel Ernest and Justin Zoppe) have in the last year finished their core course work and are now concentrating on their doctoral research to complete their degree requirements. During the previous year, Justin Zoppe has completed all of the required coursework including: Forest Biomaterials Seminar passed both Ph.D. preliminary oral exams. These included an informal preliminary exam which he presented and defended his planned research to complete his PhD. He also presented and defended a formal preliminary defense in which he discussed his research and a second proposition that was a research proposal outside of his research area. Justin also completed a research study abroad at the Department of Forest Products Technology, Aalto University, Espoo, Finland (01/2010-05/2010). During Justins research study abroad at Aalto University, he performed studies regarding the thermo-responsiveness of poly(NiPAAm)-g-CNCs utilizing rheometry, light transmittance, and Colloidal Probe-Atomic Force Microscopy (CP-AFM) to study surface interaction forces of spin-coated films of poly(NiPAAm)-g-CNCs with various grafting densities and degrees of polymerization. During the evaluation period of 11/15/2009 to 11/14/2010, Kelley wrote and defended her first and second propositions in the form of the formal preliminary oral exam. Her research activities involved further defining the effects of energy input into the properties of microfibrillated cellulose materials using three different mechanical input devices. She also investigated the effect of fillers and coatings on microfibrillated cellulose films. She published two manuscripts and has progressed in preparing for publication two additional manuscripts about the processing, lignin, and filler effects on microfibrillated celluloses. During the summer, she hosted an NC SEED student, a program focused on helping disadvantaged youth prepare for college. She presented a webinar for Microfluidics, Inc. attended by approximately 200 people worldwide. She presented an oral presentation in San Francisco at the national ACS meeting, and prepared two oral presentations for the Bioenvironmental Polymer Society meeting in Canada and the TAPPI nanotechnology conference in Finland. She also continued to mentor an undergraduate and assisted him in obtaining a research grant from the College of Natural Resources and NCSU. Rachel Ernest is preparing a submission of work involving surface acetylation of highly-fibrillated cellulose and properties of films prepared from these fibrils. Ernests esterification research led her to more heavily focus on amidization to achieve cross-linking between highly-fibrillated cellulose fibrils and poly(gamma-glutamic acid). She is also beginning to culture γ-PGA in-house. PRODUCTS: The three students were provided stipends from the USDA for a semester and the department for a semester and fringe benefits and tuition from the department. Several presentations were delivered or prepared by the students. The website describing the program, http://www.ncsu.edu/project/cnr/nnf/ has been updated. During the past year, Justin has mentored new group members (Ph.D. students) in beginning their research and has become a leader in the group. In addition, Justins five-month research study abroad in Espoo, Finland has given him a global view of importance of natural resources research and a great cultural experience. So far, Justin has participated in four ACS meetings and presented posters in two national meetings, and presented oral presentations at two international conferences: 47th Nordic Polymer Days in Helsinki and 2010 TAPPI Nanotechnology for the Forest Products Industry in Espoo, Finland. Spence hosted an NC SEED high school student from a disadvantaged background to do a summer research project and prepare for college. She presented a webinar for Microfluidics, Inc. attended by approximately 200 people worldwide. She also presented a National ACS talk in San Francisco, and prepared oral presentations for the Bioenvironmental Polymer Society meeting in Canada and the TAPPI nanotechnology conference in Finland, delivered by her advisors. She also continued to mentor an undergraduate student. Ernest initiated a collaboration with ACS-SEED program and recruited two high school students from under-represented backgrounds to come to the department for a summer research experience. One of the ACS-SEED students learned basic rheology and how to take and analyze rheological measurements of varied gamma-PGA solutions under the advisement of Ernest. OUTCOMES: The objective of this proposal is to develop a unique training program to produce outstanding graduates to meet the future needs of a globally interconnected, technologically advanced, rapidly diversifying and consumer driven wood and wood based fiber industry. New wood based advanced materials will be developed and structure/chemistry/properties relationships developed. Currently, three well-trained individuals are being developed as doctoral researchers in the areas of wood and wood-based fiber. DISSEMINATION ACTIVITIES: A website has been established and updated describing the program, http://www.ncsu.edu/project/cnr/nnf/. Research activities have been described at several technical conferences listed below. Spence presented her research on the Production of Microfibrillated Cellulose by Various Processing Methods at the American Chemical Society, 239th ACS National Meeting, San Francisco California, March 21-26, 2010. She also created a presentation on Advances in the Processing of Microfibrillated Celluloses for Bioplastic and Composite Reinforcement Applications, presented by her advisor at the BioEnvironmental Polymer Society, 18th Annual Meeting, Toronto, Ontario, Canada, October 13-15, 2010. Her research was also described in the presentation of Aspects of Raw Materials and Processing Conditions on the Production and Utilization of Microfibrillated Cellulose, presented by her advisor at the TAPPI, 2010 TAPPI International Conference on Nanotechnology for the Forest Product Industry, Espoo, Finland, September 27-29, 2010. Spence delivered an internet presentation on Case Study: Large-Scale Production of Biodegradable Plastics Using Energy Efficient Processes. Microfluidics Incorporated Webinar, August 25, 2010, attended by about 200 international people. Zoppe presented two international presentations on his research, Stimuli-responsive Polymer Brushes Grafted from Cellulose Nanocrystals via SET-LRP: Suspension and Surface Behavior, 2010 TAPPI Intl Conference on Nano for the Forest Product Industry, Espoo, Finland (September 2010) and Cellulose Nanocrystals grafted with poly(N-isopropylacrylamide) brushes via Surface-Initiated Atom Transfer Radical Polymerization, 47th Nordic Polymer Days Conference 2010, Helsinki, Finland (May 2010). Ernest prepared an oral presentation detailing her esterification work with CDI chemistry for the ACS meeting in San Francisco (presented by her advisor). She also presented an oral presentation concerning her groups work with highly-fibrillated cellulose at the June 2010 Progress in Paper Physics meeting in Montreal. At the ACS Local Section Meeting in September 2010, Ernest presented a poster sharing her acetylation work with highly-refined fibrils. FUTURE INITIATIVES: In his last year as a Ph.D. student, Zoppe will develop the use of poly(NiPAAm)-g-CNCs into thermo-responsive Pickering emulsions. A variety of oils and ionic strengths will be tested in order to optimize emulsions and study the rheological behavior with temperature and concentration of nanoparticles. Spences research will entail the further evaluation of composition, structure, properties and performance of microfibrillated cellulose materials. Ernest will continue to develop a cross-linking system using amidization and CDI chemistry to develop biomaterials with improved water interaction and material properties. Characterization of these materials will include SPR, IR, XPS, and mechanical and water tests. She will also be fully characterizing (SEC, IR, and NMR) and using the gamma-PGA cultured in-house. Ernests work with re-hydration of fibrils with the use of gamma-PGA will also continue.
Impacts
The area of Wood and Fiber Engineering is a critical research area that requires excellent research leaders in the field, three of which are being nurtured in this project. Further, this project is developing a program in which to train these types of individuals. Through the research, new materials and new understandings of advanced wood based materials is also being developed as a product of the doctoral training program.
Publications
- Spence, K., Venditti, R., Habibi, Y., Rojas, O., and Pawlak, J. 2010. The effect of chemical composition on microfibrillar cellulose films from wood pulps, processing and physical properties. Bioresource Technology. 101: 5961-5968.
- Spence, K., Venditti, R., Habibi, Y., Rojas, O., and Pawlak, J. 2010. The effect of chemical composition on microfibrillar cellulose films from wood pulps, water interactions and physical properties for packaging applications. Cellulose. 17: 835-848.
- Zoppe, J. O., Habibi, Y., Efimenko, K., Johansson, L.S., Osterberg, M., Laine, J., Venditti, R. A., Rojas, O. J., 2010. Poly(N-isopropylacrylamide) brushes grafted from Cellulose Nanocrystals via Surface-Initiated Single-Electron Transfer Living Radical Polymerization, Biomacromolecules, 11(10): 2683-2691.
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Progress 11/15/08 to 11/14/09
Outputs
All three students (Kelley Spence, Rachel Ernest and Justin Zoppe) passed their departmental qualifying exams (written and oral) in year 3 of the project. Zoppe has completed all of the required coursework including: "Forest Biomaterials Physics" and "Forest Biomaterials Chemistry" with a 4.0 GPA. He has successfully grafted poly(NiPAAm) from cellulose nanocrystals with various grafting densities and chain lengths via SI-ATRP, as well as full characterization of the resulting materials by various methods. He has also been involved in mentoring a second undergraduate student in the area of MFC hydrophobization. A third manuscript on this SI-ATRP is close to submission. He prepared for a research study abroad in Espoo, Finland at the Helsinki University of Technology (HUT) (Aalto University School of Science and Technology) which begins on January 15, 2010 until June 2, 2010. Ernest completed her final two core courses (Spring 2009 and Fall 2009) and two microbiology courses (Microbial Diversity and Core Technologies in Molecular and Cellular Biology)with a GPA of 4.0. Ernest researched the esterification of highly-fibrillated cellulose fibrils and poly(gamma-glutamic acid) with various solvent/catalyst systems and curing regimes. She characterized products with thermal analysis, water interaction properties, and FTIR. Rheological properties of poly(gamma-glutamic acid) solutions were preliminarily identified. Spence completed her departmental required coursework with a GPA of 4.0/4.0. Kelley prepared three manuscripts pertaining to the processing and lignin effects on microfibrillated celluloses. She worked on a project with Microfluidics, Inc. that investigated the effect of processing methods on microfibrillated celluloses, the subject of the third manuscript and upcoming oral presentation in San Francisco at the national ACS meeting. PRODUCTS: The three students were provided stipends from the USDA and fringe benefits and tuition from NCSU. Several presentations were delivered by the students. A website has been produced describing the program, http://www.ncsu.edu/project/cnr/nnf/. Zoppe has mentored another undergraduate student performing research. He trained the student in common wet chemistry methods, and air/moisture sensitive organic reactions similar to the previous. Zoppe won 1st prize in the Eastman Chemical Graduate Student Award competition for writing and presenting his work on SI-ATRP from cellulose nanocrystals. Zoppe has participated in four ACS meetings and presented posters in two national meetings to date. Ernest was awarded 1st place for poster presentation at Local Triangle ACS meeting September 23, 2009. Ernest also was awarded 2nd place for a written and oral presentation for Eastman Chemical Graduate Award in the Wood and Paper Science Department at NCSU. Spence continued to mentor an undergraduate and assisted him in obtaining a research grant from the College of Natural Resources and NCSU. OUTCOMES: The objective of this proposal is to develop a unique training program to produce outstanding graduates to meet the future needs of a globally interconnected, technologically advanced, rapidly diversifying and consumer driven wood and wood based fiber industry. New wood based advanced materials will be developed and structure/chemistry/properties relationships developed. Currently, three well-trained individuals are being developed as doctoral researchers in the areas of wood and wood-based fiber. DISSEMINATION ACTIVITIES: A website has been established describing the program, http://www.ncsu.edu/project/cnr/nnf/. Research activities have been described at several technical conferences. Justin won 1st prize in the Eastman Chemical Graduate Student Award in the Wood and Paper Science Department at NCSU competition for writing and presenting his work on SI-ATRP from cellulose nanocrystals. So far, Justin has participated in four ACS meetings and presented posters in two national meetings. Ernest presented on oral presentation at the American Chemical Society, 237th national meeting, Salt Lake City March 21-27 2009, presented a poster at the Local Triangle ACS meeting on 23 Sept 2009 and presented a written and oral presentation at the Eastman Chemical Graduate Award in the Wood and Paper Science Department at NCSU. Spence presented a poster titled, Production of Microfibrillated Cellulose Utilizing Various Processing Methods - American Chemical Society, Local Section Meeting RTP September 23, 2009, a second poster titled, Water Interactions of Microfibril Cellulose of Varying Chemical Compositions - American Chemical Society, 237th national meeting, Salt Lake City March 21-27 2009 and an oral presentation titled, Wood pulp chemical composition effects on the development of microfibrillated cellulose - American Chemical Society, 237th national meeting, Salt Lake City March 21-27 2009. All three students presented a recruiting poster at the ACS National Meeting in 2009. FUTURE INITIATIVES: Zoppe plans to use the various ATRP modified cellulose nanocrystals to make films and determine responsiveness of polymer grafts by performing surface force measurements using AFM in liquid, as well as turbidity measurements, during his international experience at HUT. In addition, Zoppe will perform XPS characterization of all materials at HUT. Hopefully with this research at HUT, a fourth manuscript will be written on the responsiveness of poly(NiPAAm) grafted cellulose nanocrystals. Ernest will determine the post-dried recovery properties of highly-refined cellulose fibrils when treated with poly(gamma-glutamic acid) [PGA]. Ernest will continue developing the heterogeneous esterification of highly-fibrillated cellulose fibrils and PGA to create biomaterials with improved water interaction and material properties. The products will be characterized via thermal and mechanical analysis, water absorption, saponification, and IR and NMR analysis. Ernest will be culturing Bacillus species for an internal supply of PGA along with investigating the metabolism of these bacteria with hemicellulose and cellulosic fibril slurries. She will also work with recombinant DNA to alter the metabolism and polyamide product formation. Spence expects to further investigate the role of lignin in MFC films. She will produce films with various amounts and states of lignin. It is expected that she perform analysis of these films during an international experience to HUT, as Zoppe is doing. She will also mentor undergraduate students in various aspects of MFC film manufacture and analysis.
Impacts
The area of Wood and Fiber Engineering is a critical research area that requires excellent research leaders in the field, three of which are being nurtured in this project. Further, this project is developing a program in which to train these types of individuals.
Publications
- Spence, K., Tucker, J., and Hart, P. 2009. Comparison of various hardwood Kraft pulp pre-bleaching techniques. TAPPI Journal. April, p 10-14.
- Spence, K., Venditti, R., Rojas, O., 2009. Sugar surfactants in paper recycling. Nordic Pulp and Paper Research Journal. 24(1), p 107-111.
- Zoppe, J. O., Peresin, M. S., Habibi, Y., Venditti, R. A., Rojas, O. J., 2009. Reinforcing Poly(ε-caprolactone) Nanofibers with Cellulose Nanocrystals, ACS Applied Materials & Interfaces, 1(9), 1996-2004.
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Progress 11/15/07 to 11/14/08
Outputs
In year 2, the three students (Kelley Spence, Rachel Ernest and Justin Zoppe) were expected to successfully complete their courses and choose a research project and advisor. They were also required to pass 2 out of the 4 departmental qualifying exams and to defend a first research proposition. All three students earned a 4.0 GPA. Drs. Richard Venditti, Orlando Rojas, and Joel Pawlak were assigned as research advisors for the students. With regards to qualifying exams, the department revamped its qualifying exam structure and delayed offering the exams until the following year. All three students are now slated to take the qualifying exams (written and oral) in year 3 of the project. Spence concluded a Natural Surfactants for Paper Recycling project, discussing her results at three conferences, presenting a departmental seminar, and submitting a manuscript to the Nordic Pulp and Paper Research Journal, which was accepted for publication. For her dissertation work, Spence will focus on the production, properties and applications of microfibrillated structures. For her research, she completed a homogenizer study which investigated the effect of pulp chemical composition on the production of microfibrillated cellulose and on fibril and film properties. Ernest's research activities began with developing a procedure to manufacture modified cellulose aggregate fibrils (CAF). This was initiated in collaboration with Spence. To determine the contribution of hydrogen bonding to the strength of CAF films, a heated acetylation method was used to demonstrate that films with reduced hydrogen bonding had decreased tensile strength. Ernest developed a vacuum-dewatering, heated-press film production method for CAF. In August 2008, Ernest began research to investigate bacterial culturing and biosynthesis of poly-glutamic acid and its possible contributions to enhancing composite material properties. This work involved interdisciplinary activities with the microbiology department (Dr. Amy Grunden and graduate student Anthony A. Devine) to identify bacteria present in CAF slurries. Ernest learned and practiced advanced microbiology lab techniques such as DNA isolation and amplification, cloning, DNA size characterization, microbial culturing, bacterial identification, and phylogenetic tree development. Zoppe has built a Schlenk manifold setup suitable for surface modification via Atom Transfer Radical polymerization (ATRP). He was also much involved in the selection and acquisition of an ultracentrifuge for the department and worked with the production and separation of cellulose nanocrystals. Zoppe has been successful in the production of cellulose nanocrystals based from cotton and ramie fibers by acid hydrolysis and incorporating these nanocrystals into electrospun nanofibers of poly(caprolactone). As a result of his work he has been able to produce nanofiber composites with enhanced thermal and strength properties. He has also been involved in the area of microfibrillated cellulose hydrophobization. PRODUCTS: The three students were provided stipends from the USDA and fringe benefits and tuition from NCSU. Several presentations were delivered by the students. A website has been produced describing the program, http://www.ncsu.edu/project/cnr/nnf/. Spence mentored a freshman in research, supervising research in the area of characterization of CAF based films, and also assisting the student to obtain an Undergraduate Research Award from North Carolina State University. Ernest acted as the graduate student mentor for an undergraduate student in summer of 2008 participating in the Research Experience for Undergraduates program. With this student, Ernest developed a vacuum-dewatering, heated-press film production method. Zoppe also has mentored an undergraduate student performing research for the first time. He trained the student in common wet chemistry methods, and air/moisture sensitive organic reactions. Also, Zoppe taught the student FTIR spectroscopy basics. OUTCOMES: The objective of this proposal is to develop a unique training program to produce outstanding graduates to meet the future needs of a globally interconnected, technologically advanced, rapidly diversifying and consumer driven wood and wood based fiber industry. New wood based advanced materials will be developed and structure/chemistry/properties relationships developed. Currently, three well-trained individuals are being developed as doctoral researchers in the areas of wood and wood-based fiber. DISSEMINATION ACTIVITIES: A website has been established describing the program, http://www.ncsu.edu/project/cnr/nnf/. Research activities have been described at several technical conferences. Spence has made oral presentations at the annual meeting of the Division of Colloids and Surfaces of the American Chemical Society , held in Raleigh NC, June 2008, and the 235th ACS National Meeting, New Orleans, LA, April 6-10, 2008 on Natural Surfactants in Paper Recycling. She also participated in the 2008 Soft Matter Poster competition. A manuscript on the subject of fiber recycling and natural surfactants will be published in Nordic Pulp and Paper Research Journal, a venue with the highest ISI Impact factor in the field. In July 2008 at the ACS Green Chemistry Summer School, Ernest presented a poster discussing her work with bonding characterization and strength of cellulose aggregate fibril films. Zoppe presented a poster on ATRP modification of cellulose fibers and nanocrystals at the 235th ACS National Meeting, New Orleans, LA, April 6-10, 2008 and at the ACS 82nd Colloids and Surfaces meeting. FUTURE INITIATIVES: Spence will use the current results to optimize the production of microfibrillated cellulose with various chemical pretreatments. She will then use the optimized production procedure to make samples to be coated with materials in supercritical carbon dioxide. These coatings will impart new properties on the materials which can potentially be utilized in new types of biomaterials. Ernest will be creating composites of cellulose aggregate fibrils (CAF) and poly(glutamic acid) at varying component concentrations and curing conditions. The cross-linking effects will be characterized via differential scanning calorimetry and mechanical analysis. Ernest will be investigating the culturing of Bacillus bacterial species with cellulose aggregate fibril slurries to find optimum conditions for growth and polyamide biosynthesis. In addition to the synthesis of polyamides, Ernest will be determining the component ratios and effective methods to create composite films and solid forms with desirable material properties. This work could lead to the replacement of current petroleum-derived materials with renewable and bio-degradable materials. Zoppe's research will focus on comparison of properties of surface-modified cellulose nanocrystals within different fiber nanocomposites. The methods of surface modification include grafting onto and grafting from via ATRP. Also, Zoppe plans to use ATRP to develop stimuli-responsive cellulose surfaces which can be monitored by Quartz Microgravimetry techniques and Surface Plasmon Resonance.
Impacts
Wood and Fiber Engineering will be a critical research area to support the inevitable need of the United States to develop sustainable and environmentally benign resources for society, to decrease the dependence on nonrenewable oil, and to improve the economics of the forestry/wood-based industry. Further, the domestic wood and wood-fiber industries are under extreme pressure from overseas competitors; new products must be developed to re-invigorate the US industries. This can only happen with excellent research leaders in the field, three of which are being nurtured in this project. This project is developing a pathway to develop more of these individuals.
Publications
- No publications reported this period
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Progress 11/15/06 to 11/14/07
Outputs
We conducted a recruiting program for the three NNF positions available. This included visits of faculty to other universities and centers, postings of opportunities through the internet, mailings to other institutions, and direct contacts between our faculty members and other faculty members in similar institutions. We were able to recruit three well-qualified students. Two of the students (Spence and Zoppe) that began in the Fall of 2008 started their research effort by working on characterizing sugar surfactants and their behavior in paper recycling operations, an effort to improve sustainability and better use of cellulosic materials. Spence and Zoppe have taken several critical courses in their education "Unit operations", "Interfacial Phenomena" and "Principles of Biomaterials Science" in the Fall of 2007. The third student (Ernest) started January of 2008. All three students are taking "Wet End Chemistry", Biomaterials Characterization, Atomic Force Microscopy,
and the Graduate Research Certificate course Spring 2008. All three of the students have completed a review of a set of materials that were given to them by the PDs (a selection or papers relevant to their research). The students have received safety training and are now fully engaged in their research projects. We have had regular meetings and discussed progress and plans. Sub-meetings on a weekly, individual basis are also being held.
PRODUCTS: Two publications.
OUTCOMES: The objective of this proposal is to develop a training program to produce outstanding graduates to meet the future needs of a globally interconnected, technologically advanced, rapidly diversifying and consumer driven wood and wood based fiber industry. New wood based advanced materials will be developed and structure/chemistry/properties relationships developed.
DISSEMINATION ACTIVITIES: Advertising for the recruitment of NN fellows included visits of faculty to other universities and centers, postings of opportunities through the internet, mailings to other institutions, and direct contacts between our faculty members and other faculty members in similar institutions. Further, the publications listed disseminated some of the research activities for the program.
FUTURE INITIATIVES: Rachel Ernest's research will focus on the use of cellulose aggregate fibrils (CAF) to construct films. These films, which are made of renewable biomass materials and are completely biodegradable or recyclable, could potentially replace polyethylene or other plastics derived from petroleum. The structural and physical properties of these CAF films will be evaluated relative to the current market films. In addition to the actual film creation and testing, a piece of the project will center on life cycle analysis, including economics, raw material sourcing, scale production, marketing, and product recovery. Kelly Spence's proposed area of research as a National Needs Fellow is the production optimization of cellulose aggregate fibrils (CAFs), and their use for advanced applications such as adsorbents, absorbents, and composites. The production of CAFs requires a large amount of energy, and it is planned to optimize this energy requirement by modifying pH and using
various solvents. The materials produced will be analyzed using nitrogen adsorption, differential scanning calorimetry, atomic force microscopy, and fiber quality analysis and structure/chemistry/properties relationships developed. Justin Zoppe will work on the selective grafting of cellulose nanofibers (microfibrillar cellulose) and nanocrystals to produce new biomaterials. Targeted applications are the production of nanocomposites with improved functional properties, including mechanical strength and biodegradability at low density and cost. Our initial efforts will involve reinforcing polymeric matrices with cellulose nanocrystals (CN). Our proposed method to increase component compatibility involves grafting polymer chains from the matrix onto the CN surface before composite preparation. We will graft polymeric side chains from polycaprolactone and other polymers to the CN surface using three methods: (1) polymers, carrying reactive end groups, will be attached to the CN by
coupling reactions (grafting onto). (2) Alternatively, ring opening polymerization (ROP) from CN surface (grafting from), and, finally, (c) application of grafting-from techniques via Atom Transfer Radical Polymerization will be carried out. Results from these procedures and the ensuing thermo-mechanical properties of the nanocomposites will be compared.
Impacts
Wood and Fiber Engineering will be a critical research area to support the inevitable need of the United States to develop sustainable and environmentally benign resources for society, to decrease the dependence on nonrenewable, fossil oil, and to improve the economics of the forestry/wood-based industry. Further, the domestic wood and wood-fiber industries are under extreme pressure from overseas competitors; new products must be developed to re-invigorate the US industries. This can only happen with excellent research leaders in the field.
Publications
- Natural Surfactants for Flotation Deinking in Paper Recycling, R. A. Venditti, O. J. Rojas, H. Morris, J. Tucker, K. Spence, C. Austin, L. G. Castillo, 8th Research Forum on Recycling, Niagara Falls CA, September 23-26, 2007.
- Natural surfactants in paper recycling. K. L. Spence, O. J. Rojas, R. A. Venditti, J. Zoppe, Spring Program of the American Chemical Society, April 2008, New Orleans.
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