Biopolymers for Fibers, Textiles, and beyond… Satish Kumar School of Materials Science and Engineering Georgia Institute of Technology Atlanta, GA 30332-0295 Email: [email protected] 1 Fibers in 1900 Fibers Today • Cotton • Wool • Silk Polyester, Nylon, Polypropylene, Polyethylene Aramids Carbon SiC Others World-wide synthetic fiber production is currently at ~100 billion lbs annually 2 A Low cost textile fibers containing biomaterials B High performance PAN/CNC based carbon fibers C Functional fibers based on polymer/CNC/nano-materials D High surface area carbon from lignin for supercapacitor, battery, catalysis… 3 Thermally and electrically conducting polymeric fibers PEK/CNT Fibers • Axial electrical conductivity 240 S/m • Thermal conductivity as high as 17 W/m/K • Density ~1.3 g/cm3 Polymer, 51, 3940-3947 (2010) Review of Scientific Instruments, 83, 016103 (2012) 4 PAN/CNT – early developments At 10% CNT, 50 times increase in modulus at 140 oC, and 40 oC increase in Tg Individual CNT in PAN matrix 5 nm TV Sreekumar, T Liu, BG Min, H Guo, S Kumar, RH Hauge, RE Smalley, Advanced Materials, 16(1), 58 (2004). 5 Optical Properties of Polymer/CNT Films and Fibers van Hove transitions in SWNT dispersion and PVA/SWNT films Absorbance (a. u) Anisotropic Infra-red absorption in PAN/SWNT fiber d c b a 300 400 500 600 700 800 900 Wavelength (nm) (a)PVP/SDS/SWNT aqueous dispersion (b)PVA/PVP/SDS/SWNT film (1 wt% SWNT) (c) PVA/PVP/SDS/SWNT film (5 wt%) (d)PVA/SWNT film (1 wt%) • TV Sreekumar, T Liu, BG Min, H Guo, S Kumar, RH Hauge, RE Smalley, Advanced Materials, 16(1), 58 (2004). • XF Zhang, T Liu, TV Sreekumar, S Kumar, VC Moore, RH Hauge, RE Smalley, Nano Lett, 3(9), 1285 (2003). 6 Multi-functional Fibers Light weight super-paramagnetic polymeric fibers (a) (b) We are processing polymeric fibers with super-paramagnetic properties and good mechanical properties. These fibers will also have microwave absorption capability. Potential applications: textiles, actuators, inductors etc. Polymer, 2014 Use of CNT in Polymers for heating applications Voltage (V) PAN/CNT composite fibers with 20wt% MWNT 0 150 μA 12.8 V Temperature trace line 0.5 mm ∆T (oC) +4.5 +4.0 +3.0 +2.0 +1.0 - 0.0 - 1.0 - 2.0 X 0 μm Y 80 40 ∆T = 0.00017 I2 R2 = 0.966 0 200 μm 400 μm 80 120 Tmax (oC) Y 60 Experimental Tmax 160 X 40 Estimated Tmax 200 ∆T = 4.5 oC 20 0 200 400 600 800 1000 Electrical Current (A) The composite fibers can be used as active heating materials or heating fabrics. A.C. Chien et al., Polymer, 2014 8 Schematic description of fiber spinning system As spun fiber 9 Functional Fibers Using this approach functional fibers can also be made using other nano materials – introducing corresponding functionality in the sheath or in the core. A different nano material and hence a different functionality can be introduced in each component. Fibers, with three or more components and hence correspondingly more functionalities, can be made. These fibers can be made with diameters down to about 50 nm. 10 Opportunities • Reduce cost of textiles and technical textile fibers by incorporating lignin without compromising properties and potentially even enhancing properties. • Polymer/CNC fibers with with enhanced properties. • Fibers containing CNC, lignin, CNT, magnetic particles, and other nano materials to impart added functionality…..electrical, thermal, optical, magnetic, ….. • To use lignin to make high surface area low cost carbon for battery, supercapacitor, and catalysis application ……We are just beginning the fibers revolution 11 Messages From This Presentation [Satish Kumar] • Possible applications of the insights/techniques/ findings/opportunities in this presentation – – – – A B C D Low cost textile fibers containing biomaterials High performance PAN/CNC based carbon fibers Functional fibers based on polymer/CNC/nano-materials High surface area carbon from lignin for supercapacitor, battery, catalysis… • Barriers and challenges to success – A Specific processing conditions for given systems and required properties. – B Develop markets for these new materials • Additional research opportunities – A – B Low cost - Process polymer/lignin (bi-component) low cost fibers PAN/CNC fibers – this work is currently underway at single filament scale, and can be scaled up to multi-filament scale – C Specific nano materials can be used in conjunction with CNC to impart variety of functionalities to the fiber – D. Develop technology for making high surface area carbon from lignin – similar to what we have done from PAN
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