Transition Temperature Microscopy · • Nanothermal analysis enables measurements of thermal...
Transcript of Transition Temperature Microscopy · • Nanothermal analysis enables measurements of thermal...
© 2010 Anasys InstrumentsI N S T R U M E N T S
Transition Temperature MicroscopyNano-scale Thermal Analysis Technique
Khoren SahagianAnasys Instruments
Steven Goodman10H Technology Inc.
I N S T R U M E N T S© 2010 Anasys Instruments
Outline
• Introduction to Nano ThermalAnalysis (NanoTA)
• Technology Overview• Transition Temperature
Microscopy (TTM)• Applications in materials
science and engineering
I N S T R U M E N T S© 2010 Anasys Instruments
About Anasys Instruments
• Founded in 2005 to expand the capabilitiesof probe microscopy and nanoscalecharacterization
• Over 100 years of combined experience inSPM, spectroscopic and thermal sciences
• Pioneers in– nanoscale thermal analysis– nanoscale IR spectroscopy
I N S T R U M E N T S© 2010 Anasys Instruments
Sample Limitations for Normal Thermal Analysis
• TMA – 500um diameter/5um thickness(minimum quartz probe dia. of 200um)
• DSC – 0.100mg highly crystalline materials,2-10 mg amorphous
• TGA – 5-10mg depending on maximumloss anticipated
• DMA – sample geometry is mode specific
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Temperature
Def
lect
ion
Tg = 152.4 °C
Nano Thermal Analysis
Sample
ThermaLever™ Probe
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Atomic Force Microscope
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Enabling technology
VI
I
* Developed incollaboration with
inventor Prof. W. King,UIUC
700 nm Scan on Rubber Blend
AFM Phase Image
•Controllable probe temperatures up to 450˚C
•Heating rates up to 600,000˚ C/min
ThermaLevers™ Probes*
<30 nmend radius
* Manufactured in partnership with
I N S T R U M E N T S© 2010 Anasys Instruments
Correlation to Bulk Thermal Analysis
Three crystalline samples and three amorphous samples were measured bybulk ThermoMechanical Analysis (TMA) and compared against LTAmeasurements.
y = 1.0088x - 3.8173
R2 = 0.9811
y = 1.0027x + 0.2778
R2 = 0.9701
y = 1.0047x + 2.9657
R2 = 0.95810
50
100
150
200
250
300
0.0 100.0 200.0 300.0
TMA onset
Na
no
Ta
On
se
t
0.1°C/s
1°C/s
10°C/s
Slopes: 1.003 - 1.009Offsets: -4 to +3ºC
Data courtesy of G. Meyers and A. Pasztor, DOW
I N S T R U M E N T S© 2010 Anasys Instruments
Technology Platforms
VESTAStand-alone Localized Thermal Analysis
nanoTA2Add-on accessory for AFM users
AFM+
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An optical image and nano-TA measurement on the fourlayers in a multilayer film composed of Nylon, PET andtwo forms of low density polyethylene.
94˚ C
88˚ C
180˚ C 218˚ C++ +
+
Example: Multilayer Film
100um
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BrightfieldOptical
Microscope
MotorizedXY and ZStages
VESTA head
- Point & Click Nanothermal Analysis
•Rapid, automated nano-TAmeasurements
•No AFM expertise required
•Transition TemperatureMicroscopy (TTM)
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Transition Temperature Microscopy
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Example TTM: LCD Multilayer Film
• High resolutionthermal imagingand analysis
• Automated pixel bypixel analysis
100um
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Selected Medical Device Applications
• UHMWPE Orthopaedic Bearings• Polyurethane Stress Corrosion Cracking• Drug Coated Stents• Extruded Catheters• Contact Lenses
I N S T R U M E N T S© 2010 Anasys Instruments
Example – Orthopaedic UHMWPE
PE (GUR 1050) 5 x 106 MW:• Virgin• Radiation cross-linked
100kGyLess alpha-tocopherol
More alpha-tocopherol
Vitamin E = alpha tocopherol:• Plasticization effect
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Example Explant UHMWPE Knee Bearing
Examine 2 specimen regions:• Multiple thermal transitions in damaged region• Undamaged region LTA like virgin material
Figure 1.3: Photograph of an explanted UHMWPE
knee bearing (a) and two regions of LTA analysis as
indicated with the arrows. Region shown in b and
indicated with upper blue arrow shows no visible
damage. Region c indicated with lower red arrow is
in the small pit. Local thermal analysis curves (e) are
shown for the two regions: Region b (blue curves
with 108ºC peak) and region c (red curves with
118ºC peaks, one of which has a second 176ºC peak.
I N S T R U M E N T S© 2010 Anasys Instruments
Selected Medical Device Applications
• UHMWPE Orthopaedic Bearings• Polyurethane Stress Corrosion Cracking• Drug Coated Stents• Extruded Catheters• Contact Lenses
I N S T R U M E N T S© 2010 Anasys Instruments
Example: Polyurethane Stress Corrosion
Environmental aginggreatly lowers Tm
SEM
Aged96.2 C
Intrinsic128.4 C
Melting deformation
nano-TA
Andy Hung(1) , Khoren Sahagian(2) , Mike Colvin(1) , Roshan Shetty(2)
1) Boston Scientific, Valencia, CA, 2)Anasys Instruments, Santa Barbara, CA
• 0.1 M CoCl2, 20% H2O2• 37°C• Constant 250 g pull• H2O2 changed 3X/week• 1 month
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ESC Region
Polyurethane
•ESCdomain122.5°C•Polyurethane135.2°C
100um
Example: Polyurethane Stress Corrosion
StressedRegion
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Selected Medical Device Applications
• UHMWPE Orthopaedic Bearings• Polyurethane Stress Corrosion Cracking• Drug Coated Stents• Extruded Catheters• Contact Lenses
I N S T R U M E N T S© 2010 Anasys Instruments
Example: Drug Coated Stents
Local Thermal Analysis Maps of Drug Distribution
S t e n tType Formulation Solvent
Brand X PDLLA + Drug A + excipients Solvent 1Brand Y PDLLA + Drug B + excipients Solvent 2Brand Z PDLLA + Drug C + excipients Solvent 3
I N S T R U M E N T S© 2010 Anasys Instruments
Selected Medical Device Applications
• UHMWPE Orthopaedic Bearings• Polyurethane Stress Corrosion Cracking• Drug Coated Stents• Extruded Catheters• Contact Lenses
I N S T R U M E N T S© 2010 Anasys Instruments
Example: Extruded Catheters, Contacts
Catheter LTA - Tm
Catheter Tm - very uniform
Contact Lens LTA – Tg(dry hydrogel)
Contact lens Tg - not consistent
I N S T R U M E N T S© 2010 Anasys Instruments
Additional Applications
• Thermal mapping of composites andpolymer blends
• Characterizing defects• Mapping film heterogeneity• In situ analysis of coating/thin film• Detecting weathering/degradation
I N S T R U M E N T S© 2010 Anasys Instruments
Applications
• Thermal mapping of composites andpolymer blends
• Characterizing defects• Mapping film heterogeneity• In situ analysis of coating/thin film• Detecting weathering/degradation
I N S T R U M E N T S© 2010 Anasys Instruments
Sample: Polypropylene,Polyethylene and“rubbery” phase
Impact Modified Polymers
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TTM - Polymer Blend
100 x 100 um TTM image
Polystyrene andPoly(methyl methacrylate)polymer blend
Scan size100 x 100microns.
TTM clearly differentiatesthe different Tg values ofthe two materials
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TTM: Fiber Reinforced Composites
Epoxy
• Interfacial bonding is critical toperformance
Contributed by Khoren Sahagian, Anasys Instruments
Temperature
100um
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Applications
• Thermal mapping of composites andpolymer blends
• Characterizing defects• Mapping film heterogeneity• In situ analysis of coating/thin film• Detecting weathering/degradation
I N S T R U M E N T S© 2010 Anasys Instruments
Sidewall Haze
• Analyze amorphous/crystallinecontent across the sample
Data courtesy of L.Germinario, Eastman
Chemical
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Defects in Extruded Film- Blood Bag
100um
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Applications
• Thermal mapping of composites andpolymer blends
• Characterizing defects• Mapping film heterogeneity• In situ analysis coating/thin film• Detecting weathering /degradation
I N S T R U M E N T S© 2010 Anasys Instruments
Measurement of thetransition temperaturegradient across a thin
film
Thin Film Heterogeneity
Film
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Mapping across PET bottle wall
Across wall
Bottom
inside outside
Measurements by K. Sahagian
PET Bottle Cross Sections
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Polyolefin Blown Film
TTMs showinhomogeneous
crystallinity
Histogram of transitiontemperatures
Bad!
Good!
LESS crystalline
MORE crystalline
I N S T R U M E N T S© 2010 Anasys Instruments
Applications
• Thermal mapping of composites andpolymer blends
• Characterizing defects• Mapping film heterogeneity• In situ analysis coating/thin film• Detecting Weathering/degradation
I N S T R U M E N T S© 2010 Anasys Instruments
TTM: Solid Lubricant Coating
Measurement of coatinguniformity of lubricant
100um
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Fiber Coupler-Mounting
129 ° C
205 ° C
Fiber
Substrate
Epoxy
Tg measurement of the thin epoxy layerholding the fiber to the substrate
100um
I N S T R U M E N T S© 2010 Anasys Instruments
Applications
• Thermal mapping of composites andpolymer blends
• Characterizing defects• Mapping film heterogeneity• In site analysis coating/thin film• Detecting weathering/degradation
I N S T R U M E N T S© 2010 Anasys Instruments
TTM: Weathering of PET Sheet
Exposed
Transition Temperature Microscopy Images
Transition Temperature peak shifted by ~ 90ºC due to weathering
Unexposed
Exposed to UV light
Unexposed to UV light
~125°C
~215°C
I N S T R U M E N T S© 2010 Anasys Instruments
Summary
• Nanothermal analysis enables measurements ofthermal properties on the micro and nanoscale
• Material characterization & identification• Spatially and time-resolved measurements• Transition Temperature Microscopy allows
automated visualization of structure andheterogeneity
• Broad applicability in material science andengineering
I N S T R U M E N T S© 2010 Anasys Instruments
Correlation to Bulk Thermal Analysis
Three crystalline samples and three amorphous samples were measured bybulk ThermoMechanical Analysis (TMA) and compared against LTAmeasurements.
y = 1.0088x - 3.8173
R2 = 0.9811
y = 1.0027x + 0.2778
R2 = 0.9701
y = 1.0047x + 2.9657
R2 = 0.95810
50
100
150
200
250
300
0.0 100.0 200.0 300.0
TMA onset
Na
no
Ta
On
se
t
0.1°C/s
1°C/s
10°C/s
Slopes: 1.003 - 1.009Offsets: -4 to +3ºC
Data courtesy of G. Meyers and A. Pasztor, DOW
I N S T R U M E N T S© 2010 Anasys Instruments
Polymer Standard Based CalibrationThree crystalline polymer samples are used to calibrate
the tip-sample interface temperature
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Advantages of tip heating
•Heating rates up to 600,000 C/min•Wide range of rate dependent studies
•Avoid re-crystallization
I N S T R U M E N T S© 2010 Anasys Instruments
Pharmaceutical Tablets
100x100 micron Acetaminophen-HPMC mixture