Nanofibres belong to a new class of fibrous materials having diameter equal to or less than 100 nm. Through a non-mechanical method of formation of nanoscale fibres electrostatically from polymer solutions or melts our research objective is to gain a fundamental understanding and investigate methods to produce nanofibres consistently and reproducibly. The ultimate goal of our research is to bridge the dimensional gap by electrospinning of multifunctional nanofibres and organize the nanofibres into linear, planar and 3-D fibrous assemblies for specific applications. We specifically focus our research in electroactive nanofibres; bioactive nanofibres; and multifunctional nanocomposite fibres. Examples of electroactive nanofibres being investigated include intrinsically conductive fibres such as polyethylenedioxythiolene(PEDT), polyaniline (PANi) and their blends. Bioactive nanofibres of interest are animal and plant based protein fibres (recombinant spider silk, silkworm silk, wool keratin, collagen, elastin, wheat gluten, corn zein etc) as well as biodegradable synthetic fibres (PLA, PGA, PLAGA). By co-electrospinning of nanoparticle, nanotubes and nanoplatelets with appropriate polymers a new family of multifunctional nanocompsoite fibres are being developed thus creating a new pathway to connect nanodimension, nanoeffects to macrostructures for a broad range of applications including energy storage, electronic devices, UHS sensors, ultra-strong lightweight composites.
Biomaterials/Surgical Implants
Building on a tradition of creative design and fabrication of fibre based surgical implants the Advanced Fibrous Materials Laboratory is dedicated to the development of a nanofibre platform for tissue engineering scaffolds for orthopedic(ligament, tendon etc), vascular (small diameter arteries, stents) and neural prostheses (brain machine interface). Of fundamental interest is the understanding of the dynamic interaction between biological cells and fibrous scaffolds at various hierarchical length scales. Through biomimetic design a family of protein nanofibres from silk fibroin and wool keratin polymers as well as collagens and elastins has been developed. Research work has also been initiated on self-expandable drug loaded polymer stents and compliance neural prostheses. To facilitate detection cells and surgical implants are labeled with quantum dot as well as other nanoparticles by co-electrosping to create fluorescent and magnetic nanofibres and threads.
Textile Structural Composites
Textile structural composites are composites reinforced by textile structures dedicated for load bearing applications. With a focus on the engineering design and manufacturing science of complex 3-D fiber architecture the research of the Advanced Fibrous Materials group, having a symbiotic relation with the AMPEL composite group, spans over a broad range of length scales including large diameter braiding to micro and nanosacle braiding and nanofibre placement. An example of our research is to combine textile preforming process with composite formation process as illustrated in the Briadtrusion process by combining the braiding with pultrusion. Through hybridization and gradient design a major emphasis of our research is the development of high damage tolerant and damage resistant fibre-based structures for armors as well as vehicle safety products. To facilitate communication between structural design engineers and textile manufacturing technologists a Fabric Geometry Model has been developed thus creating a framework for the integration of design for manufacturing of textile structural composites.
Publications
Refereed Journal Publications
Song, L, Du, P, Xiong, J, Ko, F, Cui, C, Efficiency enhancement of dye-sensitized solar cells by optimization of electrospun ZnO nanowire/nanoparticle hybrid photoanode and combined modification, Electrochimica Acta, 2015, 163, 330-337
Soltanian, S.; Servati, A.; Rahmanian, R.; Ko, F.; Servati, P. Highly piezoresistive compliant nanofibrous sensors for tactile and epidermal electronic applications. Journal of Materials Research 2015, 30, 121-129.
Wan, L. Y.; Wang, H.; Gao, W.; Ko, F. An analysis of the tensile properties of nanofiber mats. Polymer 2015, 73, 62-67.
Yu, Q.; Bahi, A.; Ko, F. Influence of poly (ethylene oxide)(peo) percent and lignin type on the properties of lignin/peo blend filament. Macromolecular Materials and Engineering 2015.
Vidotti, H. A.; Manso, A. P.; Leung, V.; do Valle, A. L.; Ko, F.; Carvalho, R. M. Flexural properties of experimental nanofiber reinforced composite are affected by resin composition and nanofiber/resin ratio. Dental Materials 2015.
Huizing, R. N.; Ko, F. K., Selective water vapour transport membranes comprising a nanofibrous layer and methods for making the same. US Patent 8,936,668: 2015.
Chen, L.; Yang, R.; Guo, X.; Kong, Q.; Yang, T.; Jiao, K. A novel three-dimensional interconnected graphene–zinc oxide nanowall via one-step co-electrochemical deposition. Materials Letters 2015, 138, 124-127.
Zhong, Y.; Leung, V.; Wan, L. Y.; Dutz, S.; Ko, F. K.; Häfeli, U. O. Electrospun magnetic nanofibre mats–a new bondable biomaterial using remotely activated magnetic heating. Journal of Magnetism and Magnetic Materials 2014.
Yu, Q.; Xu, S.; Zhang, H.; Gu, L.; Xu, Y.; Ko, F. Structure–property relationship of regenerated spider silk protein nano/microfibrous scaffold fabricated by electrospinning. Journal of Biomedical Materials Research Part A 2014, 102, 3828-3837.
Wang, J.; Long, H.; Soltanian, S.; Servati, P.; Ko, F. Electro-mechanical properties of knitted wearable sensors: Part 2–parametric study and experimental verification. Textile Research Journal 2014, 84, 200-213.
Leung, V. Hartwell, R.; Elizei, S. S.; Yang, H.; Ghahary, A.; Ko, F. Postelectrospinning modifications for alginate nanofiber‐based wound dressings. Journal of Biomedical Materials Research Part B: Applied Biomaterials 2014, 102, 508-515.
Huizing, R.; Mérida, W.; Ko, F. Impregnated electrospun nanofibrous membranes for water vapour transport applications. Journal of Membrane Science 2014, 461, 146-160.
He, T.; Zhou, W.; Bahi, A.; Yang, H.; Ko, F. High permeability of ultrafiltration membranes based on electrospun pvdf modified by nanosized zeolite hybrid membrane scaffolds under low pressure. Chemical Engineering Journal 2014, 252, 327-336.
Goudarzi, A.; Lin, L.-T.; Ko, F. K. X-ray diffraction analysis of kraft lignins and lignin-derived carbon nanofibers. Journal of Nanotechnology in Engineering and Medicine 2014, 5, 021006.
Gao, G.; Karaaslan, M. A.; Kadla, J. F.; Ko, F. Enzymatic synthesis of ionic responsive lignin nanofibres through surface poly (n-isopropylacrylamide) immobilization. Green Chemistry 2014, 16, 3890-3898.
Dallmeyer, I.; Lin, L. T.; Li, Y.; Ko, F.; Kadla, J. F. Preparation and characterization of interconnected, kraft lignin-based carbon fibrous materials by electrospinning. Macromolecular Materials and Engineering 2014, 299, 540-551.
Dallmeyer, I.; Ko, F.; Kadla, J. F. Correlation of elongational fluid properties to fiber diameter in electrospinning of softwood kraft lignin solutions. Industrial & Engineering Chemistry Research 2014, 53, 2697-2705.
Chae, T.; Yang, H.; Ko, F.; Troczynski, T. Bio‐inspired dicalcium phosphate anhydrate/poly (lactic acid) nanocomposite fibrous scaffolds for hard tissue regeneration: In situ synthesis and electrospinning. Journal of Biomedical Materials Research Part A 2014, 102, 514-522.
Cao, Q.; Wan, Y.; Qiang, J.; Yang, R.; Fu, J.; Wang, H.; Gao, W.; Ko, F. Effect of sonication treatment on electrospinnability of high-viscosity pan solution and mechanical performance of microfiber mat. Iranian Polymer Journal 2014, 1-7.
Badrinarayanan, P.; Ko, F. K.; Wang, C.; Richard, B. A.; Kessler, M. R. Investigation of the effect of clay nanoparticles on the thermal behavior of pla using a heat flux rapid scanning rate calorimeter. Polymer Testing 2014, 35, 1-9.
Li,R, Che, J, Zhang, H, He, J, Bahi, A, Ko, F, Study on synthesis of ZnO nanorods and its UV-blocking properties on cotton fabrics coated with the ZnO quantum dot, Journal of Nanoparticle Research, 2014, 16 (9), 1-12
Bayat, M., Yang, H, Ko, FK, Michelson, D, Mei, A, Electromagnetic interference shielding effectiveness of hybrid multifunctional Fe 3 O 4/carbon nanofiber composite, Polymer 2014, 55 (3), 936-943
Fekri, N, Madden, JDW, Lee, NYJ, Ko, F, Michal, CA, Influence of porosity on charging speed of polypyrrole, Synthetic Metals, 2014, 187, 145-151
Soltanian S, Rahmanian R, Gholamkhass B, Kiasari NM, Ko F, Servati P, “Highly Stretchable, Sparse, Metallized Nanofiber Webs as Thin, Transferrable Transparent Conductors,” Advanced Energy Materials. 2013.
Dallmeyer, Ian. Lin, L.T. Li, Y. Ko, F. and Kadla, J. “Preparation and Characterization of Interconnected, Kraft Lignin-Based Carbon Fibrous Materials by Electrospinning,” Macromol. Mater. Eng. 2013, 298, 1–12
Refereed Conference Proceedings
Li-Ting Lin, Yingjie (Phoebe) Li, and Frank Ko “Carbon Nanotube Reinforced Lignin-based Carbon Nanofibre” 2015 paperweek conference, Montreal, QC, Canada. Feb. 2nd-5th. 2015.
Li-Ting Lin, Yingjie (Phoebe) Li, and Frank Ko “Carbon Nanotube Reinforced Lignin-based Carbon Nanofibre” 2015 FIBRE regional workshop, London, ON, Canada. March, 30th-31th. 2015.
MiJung Cho, Scott Renneckar and Frank Ko, “Lignin based composite nanofibres with nanocrystalline cellulose (NCC) by electrospinning” in Paperweek Canada 2015, Montréal, QC, February 2-5,2015.
MiJung Cho, Scott Renneckar and Frank Ko, “Can Wood Become Strong Carbon Fibres?” in FIBRE Regional Industry Connect Workshop, Western University, London, Ontario, March 30, 2015.
Mijung Cho, Frank Ko and Scott Renneckar, “Electrospinning of Lignin Based Composite Nanofibers with Nanocrystalline Celluloses” in 249th American Chemical Society (ACS) National Meeting, Denver, CO, March 22-26, 2015.
Karaaslan, M. A. & Ko, F., “Aerogels from lignin for energy storage applications”, Paperweek 2015 Conference, Montreal, QC. February 2-5, 2015. (Oral and poster presentation)
Karaaslan, M. A. & Ko, F., “Can lignin be used to produce high surface area porous carbon electrodes for energy storage?” FIBRE Industry Connect Workshop, London, ON. March 30-31, 2015. (Poster presentation)
MiJung Cho, Addie Bahi and Frank Ko, “Electrospun lignin based composite nanofibres reinforced with nanocrystalline cellulose (NCC) for carbon fibres production” in FIBRE Western Canada Workshop, Vancouver, BC, 2014.
MiJung Cho and Frank Ko, “Electrospun lignin based composite nanofibres reinforced with nanocrystalline cellulose (NCC) for carbon fibres production” in 2nd FIBRE Meeting, Vancouver, BC, 2014.
Muzaffer A. Karaaslan, MiJung Cho and Frank Ko, “Lignin-Based Carbon Aerogels” ” in 2nd FIBRE Meeting, Vancouver, BC, 2014.
Figure I. Nanofibre Technology
Figure II. Biomaterials/Surgical Implants
Figure III. Textile Structural Composites
Figure IV. Electrospinning