Cellulose Nanocrystal Cellulose Nanocrystal Characterization by AFM Characterization by AFM Roya Roya Lahiji Lahiji Post Doc @NINT Post Doc @NINT X. X. Xu Xu Mechanical Eng Mechanical Eng Ryan Wagner Ryan Wagner Mechanical Eng Mechanical Eng Arvind Raman Arvind Raman Prof. Mechanical Eng Prof. Mechanical Eng Ron Reifenberger Ron Reifenberger Prof. Physics Prof. Physics Robert Moon Robert Moon Forest Products Lab Forest Products Lab Purdue Purdue - - Materials Eng Materials Eng Birck Nanotechnology Center Birck Nanotechnology Center 2009 2009 Intn Intn ’ ’ l l Conf. on Nanotechnology for the Forest Products Industry, Conf. on Nanotechnology for the Forest Products Industry, June 24 June 24 - - 26, 2009, Edmonton, Alberta, Canada 26, 2009, Edmonton, Alberta, Canada
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Cellulose Nanocrystal Characterization by AFM · 2009-07-29 · Cellulose Nanocrystal Characterization by AFM Roya Lahiji Post Doc @NINT X. Xu Mechanical Eng Ryan Wagner Mechanical
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Cellulose Nanocrystal Cellulose Nanocrystal Characterization by AFMCharacterization by AFM
RoyaRoya LahijiLahiji Post Doc @NINTPost Doc @NINTX. X. XuXu Mechanical EngMechanical EngRyan WagnerRyan Wagner Mechanical EngMechanical Eng
Arvind RamanArvind Raman Prof. Mechanical EngProf. Mechanical EngRon ReifenbergerRon Reifenberger Prof. PhysicsProf. Physics
Robert MoonRobert Moon Forest Products LabForest Products LabPurduePurdue-- Materials EngMaterials EngBirck Nanotechnology CenterBirck Nanotechnology Center
2009 2009 IntnIntn’’ll Conf. on Nanotechnology for the Forest Products Industry, Conf. on Nanotechnology for the Forest Products Industry, June 24June 24--26, 2009, Edmonton, Alberta, Canada26, 2009, Edmonton, Alberta, Canada
OutlineOutline
MotivationMotivationAtomic Force Microscopy (AFM)Atomic Force Microscopy (AFM)ResultsResultsSummarySummary
Insight for Composite Processing & PropertiesInsight for Composite Processing & PropertiesLoad Transfer across Transverse SurfacesLoad Transfer across Transverse Surfaces
Necessary for Predictive ModelingNecessary for Predictive Modeling
Modulus of ElasticityModulus of ElasticityBased on Idealized Cellulose Based on Idealized Cellulose IIββ SimulationsSimulations
No Transverse Elasticity
Developing Characterization ProtocolsDeveloping Characterization ProtocolsWhere we are atWhere we are at…….. ……where we need to be!where we need to be!
Imaging Modes Imaging Modes Contact Contact Vibrating (non & intermittent contact)Vibrating (non & intermittent contact)JumpJumpImaging under Gas or LiquidImaging under Gas or LiquidTip Chemical FunctionalizationTip Chemical Functionalization
Atomic Force Microscopy (AFM)Atomic Force Microscopy (AFM)
TopographyTopographyStiffnessStiffnessPullPull--off forceoff force
AFMAFM--PurduePurdueNanotech AFMNanotech AFM
Si tips, 10nm tip radiusSi tips, 10nm tip radiusStiffness 0.65 N/m Stiffness 0.65 N/m (manufacturer)(manufacturer)
measure each tipmeasure each tip0.90.9--2.5N/m2.5N/m
Resonance Frequency: ~40KHzResonance Frequency: ~40KHzAtmosphere ControlAtmosphere Control
30% & 0.1% RH30% & 0.1% RH
Sharp AFM tips Sharp AFM tips (<10nm)(<10nm)Consistent tip shapeConsistent tip shapeDurableDurableLess expensiveLess expensiveImage & Property MeasurementImage & Property Measurement
AFM TipsAFM TipsSharp Sharp (<10nm)(<10nm)
Good
Ultra Sharp Ultra Sharp (<2nm)(<2nm)Inconsistent tip shapeInconsistent tip shapeFragileFragileExpensiveExpensive
Bad
10 nm
CNC: ~4CNC: ~4--10nm10nm
Mica
ArtifactsArtifactsChanging contact curvatureChanging contact curvatureEdge effectsEdge effectsAFM Tip dilationAFM Tip dilationAFM Tip bluntingAFM Tip bluntingAFM TipAFM Tip--toto--Tip changesTip changesMeniscus FormationMeniscus Formation
IIII -- PullPull--off Force off Force TipTip--Surface InteractionSurface InteractionAdhesionAdhesionCNCCNC--surface Chemistry?surface Chemistry?
II --Slope Slope CantileverCantilever--CNC stiffnessCNC stiffnessElastic ResponseElastic ResponseCNCCNC--Modulus?Modulus?
II
II
ApproachWithdraw
Force DisplacementForce Displacement
90nm
Topography
Data CollectedData CollectedTopography, PullTopography, Pull--off, Stiffnessoff, Stiffness128 x 128 points128 x 128 pointsResolution based on mapping areaResolution based on mapping area
Maps Maps TopographyTopographyStiffnessStiffnessPullPull--off Forceoff Force
~2wt% CNC suspension 400nm
Deposit ~10 μl of solution on to freshly cleaved mica sheet