Graphene Synthesis & Graphene/Polymer Nanocomposites Ken-Hsuan (Kirby) Liao Advisors: Dr. Chris Macosko Dr. Andre Mkhoyan Department of Chemical Engineering & Materials Science University of Minnesota Ph.D. Defense Minneapolis MN September 19th, 2012 1
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Ken-Hsuan (Kirby) Liao Advisors: Dr. Chris Macosko
Dr. Andre Mkhoyan
Department of Chemical Engineering & Materials Science University of Minnesota
Ph.D. Defense Minneapolis MN
September 19th, 2012
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• University of Minnesota - Ph.D. Materials Science, 2008~Present Graphene Synthesis & Graphene/Polymer Nanocomposites
• Double Bond Chemical Co - Research & Development Engineering, 2008 Polymeric Materials
• Taiwan Army, 2007~2008
• National Taiwan University - M.S. Polymer Science & Engineering, 2005~2007 MS Thesis: Thermoplastic polyurethane composites for dental materials - B.S. Chemical Engineering, 2001~2005 BS Thesis: Mechanical & thermal properties of thermoplastic polyurethane
Biography
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Graphene
0-D: Bucky Ball, 1986
1-D: Carbon Nanotube, 1991
3-D: Graphite, 1500
2-D: Graphene, 2004
Graphene Properties
Modulus 1 TPa
Strength 130 GPa
Electrical Conductivity 6000 S/cm
Surface Area 2600 m2/g
Graphene: monolayer of carbon atoms packed in 2D hexagonal manner
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Why Graphene/Polymer Nanocomposites?
Light-weight stiff materials
BMW i8, a car made with composites.
Boeing 787, contains 70,000 lb composites.
Food packaging
From Brown Machine LLC
Conductive coating
From Thermal Spray Technology Inc 4
Picture From Mission Impossible 4 From Boeing
Challenge of Graphene/Polymer Nanocomposites: Dispersion
Bicerano, Polymer, 2002, 43, 369 5
aspect ratio
>> <<
material needed
Motivation of Novel Graphene Synthesis
Criteria of Graphene Synthesis Process for Nanocomposites:
1. Massive production 2. Low cost 3. Environmental friendly process 4. Easy to transport
Idea: Disperse graphene in flowable oligomer instead of polymer for better dispersion Graphene: Vorbeck’s thermally reduced graphene (TRG)
15 Liao, K.-H. et al, Polymer, 2012, 53, 3756
Electrical Percolation & Aspect Ratio
Percolation concentration: 0.15 wt% Af of dispersed TRG: ~750 reported Af of free standing TRG: 750
Af : aspect ratio of dispersed filler σc : conductivity of nanocomposites σf : conductivity of filler r : particle radius t : particle thickness Φsphere : volume fraction of interpenetrating spheres (= 0.29) Φperc : percolation volume concentration
σc = σf (φ-φperc)t
16 Liao, K.-H. et al, Polymer, 2012, 53, 3756
Mechanical Properties of Graphene/PUA Nanocomposites