Transcript RNDr. Ján Pásztor

Reverzní inženýrství - špionáž
cizích produktů pomocí
infračervené a Ramanovy
spektrometrie
Ján Pásztor, Nicolet CZ s.r.o.
[email protected]
Motto: ŠUMĚNKA
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Motto: ŠUMĚNKA
• Originál
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Motto: ŠUMĚNKA
• Kopie
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Motto: ŠUMĚNKA
• Kopie vs. originál
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Motto: ŠUMĚNKA
• Kopie vs. originál – nalezené složky
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Motto: ŠUMĚNKA
• Kopie vs. originál – nalezené složky - detail
CUKR
KYSELINA CITRONOVÁ
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FT-IR Raw Materials Verification
Software provides a simple quality control check
•
Verification process main steps:
1. Collect spectra of the incoming materials to verify
2. Save spectra for reference (comparison) automated analysis
3. Collect and compare new incoming materials
•
Pass / Fail limits can be set
•
•
•
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Certify materials before production
Prevent product failures
Monitor consistency of suppliers
Spectral Correlation to Qualify Raw Materials
• Similar polymers, with different structure
• Infrared can reveal structural differences within the same class of compound
Example: Nylon 6,6 and Nylon 6,12 spectral differences
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Spectral Correlation to Qualify Raw Materials
0.85 HDPE High Density Polyethylene (low methyl CH3 groups shows none or little absorption at 1375)
LLDPE Linear LDPE (1375 peak of CH3 groups shifted depending on copolymer C4, C6 or C8); butene shows a 770 peak.
LDPE Low Density Polyethylene (high CH3 methyl groups shows intense 1375 peak)
0.80
0 .85
0 .80
0.75
HD PE Hig h D ens ity P olyethylen e (lo w m eth yl C H3 grou ps s ho w no ne or li ttle abs orption at 1 375 )
LL DP E Li nea r LD PE (13 75 p eak of C H3 gro ups s hi fted dep end ing on c op olym er C4, C6 or C 8); b ute ne (C6) s ho ws a 77 0 p eak.
LD PE Low De ns i ty P olye thyl ene (hig h C H3 methyl grou ps s ho w in tens e 1 375 pea k)
0 .75
0 .70
0 .65
0.70
0 .60
Absorbance
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0.65
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0 .45
0 .40
0 .35
Absorbance
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0 .25
0 .20
0.55
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0 .10
3 500
3 000
2 500
2 000
W ave num bers (c m-1 )
0.50
0.45
0.40
0.35
0.30
0.25
1390
10
1380
1370
1360
1350
Wavenumbers (cm-1)
1340
1330
1320
1 500
1 000
Analysis Output
• Software lists similar materials in the reference archive
• Highlights with ‘Pass’ those exceeding the threshold (typically 98%) of similarity
Confidence is guaranteed by the correlation value
and by the nearest result correlation difference
These spectra look identical to us… they are not
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FT-IR Quantitative Analysis
1.
Prepare the set of samples of known concentration
•
•
One or multiple species can be measured simultaneously
ATR sampling for high concentration (above 1%), transmission for lower dosage
2.
Collect data for all standards
3.
Create a calibration curve
•
•
4.
Beer’s Lambert peak ratio methods
Chemometric methods
Analyze new samples
•
•
Software allows implementation of SOPs
Ease of use, speed and consistency
If the analytical method is available from your
supplier and it is based on a peak ratio, there is no need
for a full calibration set. In this case, a few standard
samples are sufficient to adjust the
calibration curve factors
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Common Polymer Additives IR Frequency Chart
Additive:
Irganox 1010
Irganox 1076
Irganox 3114
IR Frequency:
1746 cm-1
1741 cm-1
1697 cm-1
Irgafos 168
1215 cm-1
BHT
3648 cm-1
Chimasorb 944
1560 cm-1
Erucamide
3365 cm-1
Tinuvin 622
1738 cm-1
Polyethylene film with Erucamide
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Irganox 1076 Quantitative Analysis in Polyethylene
Polyethylene 2020 cm-1 thickness correction band
Irganox peak
Calibration curve
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New sample quant analysis report
Multi Component Quantitative Analysis
Many industries use FT-IR and NIR for the
Quantification of multiple species in one measurement
Chemometrics (PCA, PLS, PCR) are normally used for this purpose
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Screening
• Raman is a light scattering technique, no sample preparation is required
• This enables automated analysis for screening
• In this example, semiprecious gemstones, but could be anything…
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Heterogeneous Mixtures
• Bulk measurement challenges
• Non-uniform component distribution
• Particle size of each component may be distributed
over a wide range
• Single point measurements
• Measurement may not be representative of the
samples bulk formulation
• Multipoint sampling measurements
• Time consuming
• Not representative
• Solution – Variable Dynamic Point Sampling
(VDPS)
• Expand beam size up to 5 mm by rastering rapidly
across sample
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VDPS – Rastering Pattern
VDPS for Heterogeneous Mixtures
Multiple location single point measurements on a finished tablet with and without VDPS
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Tablet BEX Position A – VDPS Off
Tablet BEX Position A – VDPS On
Tablet BEX Position B – VDPS Off
Tablet BEX Position B – VDPS On
Tablet BEX Position C – VDPS Off
Tablet BEX Position C – VDPS On
Tablet BEX (Variance of 25 Sampling Points) – VDPS Off
Tablet BEX (Variance of 25 Sampling Points) – VDPS On
Integration
Built-in ATR
Solid Substrate & iS50 ATR
1800 cm-1
Ge/KBr & iS50 ATR
One detector!
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Integration
Built-in ATR
• Your talking points
• Performance of the hi-end diamond ATR, with no need for set-up, ever
• Mid and Far IR ABX without the hassle
• More convenient than a “dual detector” Mid-Far configuration
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Integration
Raman
• Press sample and go…
Press
FIR ATR
MIR ATR
Raman
With the ABX and Macros Basic you can make this a routine
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Integration
• iS50 Raman Module
• Complete software suite
• Can do everything!
• Point and shoot, line scans, area maps
• Cluster analysis / screening
• Control sample holder
• Capture images
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Raman
Measuring FAMEs in Biodiesel Blends
 Multi bounce ATR allows crystal plate
changes to fine tune path length
• 60° for high concentrations
• 45° for low concentrations
 Simple calibration and quantitation
Ester peaks
Calibration
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Classic Search with no ATR Correction
Match may look good, but the information is incorrect
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Classic Search after Advanced ATR Correction
More accurate match, but the information is incomplete
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Multicomponent Search (Patented) OMNIC Specta
• Select libraries
• Specify how many
compounds you wish to
find… up to 4 max
• Then wait…
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Multicomponent Search (Patented) OMNIC Specta
• The list of identified spectra is not a series of all similar candidates
• These are the “ingredients” of the unknown mixture!
• The Classic Search result (Novodur) was correct, but we were missing
a flame retardant such as TBBP
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Multicomponent Search (Patented) OMNIC Specta
Lot more information: your confidence improves
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Multicomponent Search (Patented) OMNIC Specta
•
•
•
•
Match index is no longer the one of “one spectrum”
Is the result of a synthetic mixture calculated by software
You have multiple mixtures to check for…
Each ingredient adds information and has a % of composite
• …which can be indicative of its concentration, semi-quantitative method
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Multicomponent Search (Patented) OMNIC Specta
• So… how the spectrum of these ingredients look like?
• A synthetic spectrum for each mixture is calculated by software…
• …so that your eyes can judge
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Analytical Services
Deformulation studies – Reverse engineering by
use of TGA and Infrared
Intimately Mixed Samples
• Solids: Formed polymer parts, pellets, beads
• Liquids: Totally miscible mixtures
• Need to analyze
• Separate or Deformulate
• Tear it apart
• Analyze
• What is it?
IR
• Why? Two scenarios
• The material fails
• Understand root cause
• The material is from another vendor (competitor)
• How do they make it?
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Vapor
Formulation and Reverse Engineering – TGA-IR
• Coupling Infrared with Thermo Gravimetric
Analysis provides an efficient way to…
• Verify compositions of known formulations
• Identify components of unknown (or
competitive) formulations
• Analyze the root cause of failures
• TGA-IR is particularly useful to study
• Polymer and rubber copolymers or blends,
including monomer composition
• Secondary components including additives,
plasticizers, stabilizers…
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Basic Idea Behind TGA-IR
• Thermal Gravimetric Analysis
• Material characterization technique
• Combines micro balance with high precision
heating
• Sample heated via user-defined heat ramp
• As sample releases vapors, TGA records
weight loss
• TGA is a quantitative analysis technique
• FT-IR for Evolved Gas Analysis
• Material identification technique
• Vapor output of TGA sent to FT-IR gas cell
(“EGA”) via heated transfer line
• Obtain spectra of the vapors released
• Adds qualitative identification
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TGA-FTIR Experiment
1 .0
1 .0
Infrared Spectrometer
Infrared Spectrum
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Absorbance
Absorbance
Absorbance
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0 .55
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IR Beam
IR Beam
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0 .20
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0 .15
0 .1
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3 500
0 .05
0 .0
IR Window
H2O
000
44000
3 000
2 500
3 000
3 000
2 500
2 500
1 500
1 5001 500
1 000
1 000 1 000
5 00
5 00
CH4
Heated Transfer Line
Furnace
Mirror
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2 0002 000
W ave
(c )m-1 )
W ave
numnum
bersbers
(c m-1
H2O4
4 CH
HCH
2O
Exhaust
2 000
W ave num bers (c m-1 )
500
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500
H2O
CH CH4CH
4
4v
Transfer
Gas In
Sample
Simple Procedure for Complex Samples
• TGA-IR analysis
• Sample loaded in TGA
• Furnace follows
programmed heating
ramp
• The infrared
spectrometer records
spectra continuously
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Root Cause Analysis – TGA IR
Gaskets analysis
Good
Good
Bad
Subtraction
Bad
Search result
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Multiple Gases from TGA of an Epoxy
• Sample emits
multiple gases
• Traditionally,
analysis via
subtractions
• OMNIC Specta:
Multi-component
analysis
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Key New Capability
• Multicomponent Search identification
• Vapor phase infrared spectra generated by TGA IR are different from solid
and liquid phase, making interpretation less intuitive
• Multicomponent Search fills this gap, using gas phase spectral libraries to
identify materials, even when simultaneously released by the furnace
• Many releases from TGA are multiple gases at same time
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Mercury TGA
Fast Answers with Search Results, Component
Profile Information and Match information all in one
window!
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Mercury GC
1. Co-adds spectra
2. List peaks by
retention time
3. Identifies
separated
substances
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Analytical Services
Failure analysis – Identification and
characterization of defects and contaminants by
FT-IR and Raman microscopy techniques
Automotive Industry and Supply Chain
• Dealing with defects and micro additives, competition studies…
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Infrared Microscopy
A technique that combines light microscopy and FT-IR spectroscopy to
analyze microscopic samples
• Point and shoot is for…
0 .18
0 .14
+
Abs
0 .12
• Single specimen identification
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0 .06
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+
0 .02
0 .00
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N y lo n L ib r a r y ma tc h
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Abs
• Fibers
• Particles
• Inclusions
• Observe, get a spectrum, and identify
R e d Fib e r e m b e d d e d in mo n e y
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0 .4
0 .3
0 .2
0 .1
0 .0
4 000
3 500
3 000
2 500
2 000
1 500
1 000
5 00
W ave num bers (c m-1 )
Polyurethane adhesive
• Mapping is for…
• Sections and small areas characterization
• Laminates
• Paint chips and other cross sections
• Small areas materials distribution studies
• Observe, get a series of spectra and identify / measure
• Imaging is for…
• Large areas characterization
• Observe, set an area, get an array of spectra
and extract information
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Polyethylene
Polyamide
EVA
EVOH
Polyethylene
Point and Shoot: Embedded Particles in Carton Box
• Packaging has multiple purposes
• Protects the product from aging effects, discoloration, contamination etc.
• Distinguishes the product in consumer’s mind by its look and feel
• If the package is defected, customer does not buy the product
• Impacting revenues and brand image
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Mapping:
Food Packaging Cross Sections
Polyurethane adhesive
Polyethylene
Polyamide
EVA
EVOH
Polyethylene
Number of layers, materials, thickness and bonding
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Laminates by Raman Microscopy
• Advantage #1
• No need for microtomes
• Straight cut of the sample held in a vice
• Disposable single cut blade used in this example
• Advantage #2
• Raman spatial resolution of 1 micron allows
identification of layers of thickness size
smaller than IR diffraction limit
• Advantage #3
• Very sensitive to structural forms /
crystallinity
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Measured section
Laminates by Raman Microscopy
1
2
3
4
5
1
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2
3
4
5
Laminates by Raman Microscopy
1
1
Thickness > 30 microns
Material: PP + ?
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Laminates by Raman Microscopy
1
• Advantage #3
• Not only TiO2 is identified as the filler of layer #1...
1
Thickness > 30 microns
Material: PP + TiO2 (Rutile form)
• Raman sensitivity to crystal forms identifies which type too
*Subtraction Result:*White PVC 780nm
Int
400
200
0
Anatase
Int
60000
40000
20000
Int
0
40000 Rutile
20000
0
800
600
400
Raman shift (cm-1)
50
200
Laminates by Raman Microscopy
Layer 2, IPDI
Thickness ~ 3 microns
2
2
Thickness > 3 microns
Material: PU – IPDI type
• Advantage #2
• Raman spatial
resolution provides...
Isophorone Diisocyanate
10 microns
• Clear, sharp spectrum
of the adhesive (high
signal to noise even if
only 3-4 micron thick)
• Excellent spectral
match
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Laminates by Raman Microscopy
3
3
Thickness ~ 15 microns
Material: Nylon 6
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Laminates by Raman Microscopy
4
4
Thickness > 3 microns
Material: PU – HDI type
• Advantage #2
• Raman spatial resolution provided...
Hexamethylene Diisocyanate
• Clear, sharp spectrum of the adhesive (high
signal to noise even if only 3-4 micron thick)
• Excellent spectral match
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Laminates by Raman Microscopy
5
5
Thickness > 30 microns
Material: PET
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Laminates by Raman Microscopy
Isophorone disocyanate
between PP and PA
(Nylon) , 3 micron thick
Summary
Nylon 6
Hexamethylene disiocyanate
between PA and PET, 3 micron
thick
Polypropylene with TiO2
rutile type (anatase has
very different properties)
Polyethylene
terephthalate (PET)
Length: 50 steps (1 micron step size)
Speed: 30s /step
Total time: 25 minutes
…no sample preparation required
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“Pimpling” Seen in Automobile Dashboard
Surface defect visible
Microtome revealed sub-surface
defect
Bulk
Defect
Spectra from bulk (1,2,6) and inhomogeneity (3,4)
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Analytical Services
Process and reaction studies – Examples of
kinetic FT-IR studies
Polyurethane Curing
• Precursor material “Blocked” against reactions
• Allows shipping in train cars
• Heat ( ) removes the blocking agent (BA)
• Reaction can now proceed
• This produces an isocyanate intermediate
• The isocyanate reacts with alcohol (ROH)
• This produces the polyurethane
Isocyanate intermediate
R”-NHC(=O)-BA
R”-N=C=O + BA-H
Polyurethane
R”N=C=O + R-O-H
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R”-NHC(=O)-O-R
Series Data for Polyurethane Reaction
Time
Bound blocking agent (red) signal disappears
Isocyanate (blue) forms, then disappears
Urethane (purple) forms
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UV Cure Study of Dymax OP 4-20641 Adhesive
• Simple way to test adhesive curing
•
•
•
•
•
Apply a thin coating of adhesive to am IR transparent window
Collect “Before curing” spectrum, in transmission
Start Series Collection: 3 scans/sec
Let run several seconds and then turn on UV Lamp for 30 sec
Collect “After” spectrum after Series Collect is complete
Set up used at Akron University in Ohio,
USA. Fiber optics UV lamps are more
compact and easier to setup
Due to the time resolution required,
MCT detector is recommended.
Attenuation filter used in the output
beam to block UV radiation (source of
noise)
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Dymax OP 4-20641 Adhesive: Before and After
DYMAX OP 4-20641 #1
2
Abs
813cm-1 Acrylate C=C
1
Abs
2
1
0.5
Abs
DYMAX OP 4-20641 #1 After
Subtraction Result:DYMAX OP 4-20641 #1
0.0
-0.5
1800
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1600
1400
1200
Wavenumbers (cm-1)
1000
800
UV Cure Study of Dymax OP 4-20641 Adhesive
UV irradiation turned ON (30s)
Most of the curing process
happens within 20 seconds
Curing completed
after 35-40 seconds
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Reaction Monitoring – Catalysis Experiments
Diffuse reflectance and OMNIC Series software
 Efficient optical design
• Provides best possible signal to noise
• Ensures best quality diffuse spectra, rejecting specular
 High temperature & pressure reaction chambers
• Enable analysis of powder under controlled atmosphere
and conditions, in a small laboratory-like scale
 Collect a series of data to understand the process
• OMNIC Series is the time based software that can be
used for previously described kinetics like TGA and GC-IR
• Applied to non separating techniques, it can be used for:
• Polymer condensation kinetics
• UV curing studies
• Catalysis
• Any type of irreversible chemical reaction to
characterize the chemistry from Time 0 to N
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Catalyst Research
• Study on reaction of NO gas with powdered TiO2
• Reaction accelerated by UV-irradiation
Source: Journal of Catalysis 237 (2006) 393–404
Jeffery C.S. Wu & Yu-Ting Cheng, National Taiwan University
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Infrared Monitoring in Rheology Experiments


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What happens to material under stress?
Infrared can reveal the effects on the molecular
structure, in real time
PUR Foam Curing Monitored via FT-IR
Spectrum taken after:
0 min
20 min
 NCO stretching decreasing
50 min
 HNCO (Amide II) combined motion increasing
0.5
0.7
40 min
 C=O/ urethane (non-bonded) stable
Absorbance Units
0.2
0.3
80 min
0.4
70 min
0.0
0.0
0.1
0.1
0.2
Absorbance Units
0.3
0.4
0.5
0.6
60 min
2350 3500
≀≀
2300
2250
3000
Wavenumber cm-1
Technik: ATR - mit Rheo
Probe:
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2200
1800
2500
2150 1750
2000 2100
Wavenumber cm-1
Anzahl
Scans:
8 - mit
Auflösung:
Probe:ATR
Technik:
Rheo 4 cm-1
17001500
1650
1000 1600
Wavenumber cm-1
30/03/2010
Technik:
- mit Rheo
Anzahl Scans:
8 ATR
Auflösung:
4 cm-1
5001550
Anzahl Scans: 8
30/03/2010
1500
Auflösung: 4 cm-1
1450
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PU Foam in Oscillatory Shear + FT-IR
 Rheology clear function of
ongoing chemistry
 Increase of G’ (G prime) function
of amide bond concentration
 Increase of G’’ (G double prime)
function of air bubble concentration
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Analytical Services
Materials distribution – Infrared imaging for
materials characterization and space distribution
What is an Infrared Chemical Image?
• Chemical imaging is the process of extracting chemical information from
the set of spectra of an X-Y plane, or area
• As an example, you may want to know if the distribution of a certain material is
uniform across your sample
• To collect an area map you can use either a single detector or an imaging
detector microscope, the latter being much faster, and a motorized
microscopy stage
• Here is the challenge!
?
• In a tridimensional plot, X and Y represent positions of the stage (area)
• Each point in the area is linked to a spectrum
• So… how do use the third axis?
• Absorbance – calculate the value from each spectrum at a specific
wavelength then report the values in tridimensional plot
• Peak ratio – define two peaks then report all values
• Similarity match – imagine to search all spectra then report similarity match
values in the tridimensional plot… and many other tools
• YOU DEFINE IT!
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mm
mm
What is Infrared Chemical Imaging?
• Chemical image by absorbance of a certain frequency
• Let us assume you are interested in the distribution across your sample of an
ester peak located at 1720 cm-1, typical of a particular chemical ingredient
Video image
• Each wavelength would provide a chemical image; you simply choose the one
you need. In this case, the third on the right
Abs @ l1 wavelength
Abs @ l2 wavelength
Abs @ l wavelength
3
y
x
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y
Chemical images x
y
x
What is an Infrared Chemical Image?
• Chemical image by absorbance of a certain frequency
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Speed of Acquisition for Large Area Maps is Critical
• Speed comparison between (Nicolet iN10 and iN10 MX taken as reference)
• Assume the area to “map is 400 x 400 microns
• Standard speed mapping
• Aperture size: 25 x 25 micron
• 1 step per second x 256 steps =
4 minutes and 30 seconds
• Ultrafast mapping
• Aperture size: 25 x 25 micron
• 10 steps per second x 256 steps =
26 seconds
• Ultrafast imaging
• 16 pixels of 25 x 25 micron each
• Linear array field of view: 400x75 micron
• Steps to fill 400 x 400 microns area: 6 steps (5+1)
• Speed: 10 steps per second (400 x 700 / sec, 160 spectra / sec)
• Total time =
0.6 seconds
…now assume the area to analyze is 4 mm2 (100X)
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Ultrafast Imaging
• Allows the acquisition of large maps, in only few minutes
• The Nicolet iN10 MX imaging, as an example, covers 5x5mm in 5 min
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Chemical Imaging
Coated Bumper
Bumper structure
Coating
Cellulose fibers
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Chemical Imaging
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Coated Bumper
Chemical Imaging is Much More than Spectral Analysis
• Thin section of a rock
• 25 micron aperture, Ultra Fast Map
• 10 steps / sec @16 cm-1
• Based on the polarized light image,
these two phases A1 and A2 have
different refractive index
• Very subtle spectral differences
between the two phases…
A1
80
• Enable Ultrafast mapping and let
chemical imaging revealing more…
A2
Common Domain A1 1 µm ;-1264 µm
A1 A2
35
%T
60
30
A1
40
25
%T
20
Common Domain A2 -274 µm ;-1439 µm
20
80
15
%T
60
20
4000
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10
40
A2
3500
5
3000
2500
2000
Wavenumbers (cm-1)
1500
1000
900
850
800
Wavenumbers (cm-1)
750
700
Different Chemical Images Extracted from Sample
Common Domain A1 1 µm ;-1264 µm
80
%T
60
40
20
Common Domain A2 -274 µm ;-1439 µm
80
%T
60
40
20
4000
3500
3000
2500
2000
Wavenumbers (cm-1)
Chemical images of domains A1 and A2 (697 cm-1 band)
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80
60
55
70
50
60
45
40
%T
%T
50
35
30
40
25
30
20
15
20
10
10
5
4000
4000
3500
3000
2500
2000
Wavenumbers (cm-1)
Domain “B”
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1500
1000
3500
3000
2500
2000
Wavenumbers (cm-1)
Domain “C”
1500
1000
Very rare domain “D”
1500
1000
Self-extraction of Usable Information from Maps
• Automated routine…
• Finds spectral classes
• Locates them in the map
• Calculates area of each
class as % of total map
• Can be used for…
• Any type of sample where
materials distribution is of
your interest (API in tablets…)
• Provides a semi-quantitative
approach when a calibration
standard set is not available
(street drugs)
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How Many Particles on this Film, and What are They?
• Main component C1 in brown
• Particles (C1 and C2) in green
• Foreign particle C3, in purple
Contaminant
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Multicomponent Search of C1 and C2 Spectra
• Break down the mixture spectrum to identify components
• Particles are made of blended silica in polypropylene (slip agent?)
Unknown & search overlay
Co-polymer film
Silica particles
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Usable Information Multiple Step Process
Correlation Chemical Image
• Find the particles and color them by
composition
• Binarize the image to enable the image
analysis tool…
• Which automatically calculates the % of
area due to particles, versus total
• Summary:
•
•
•
•
Main material of film: Polypropylene
Particles material: Silica
Contaminant particle found: skin?
Distribution of particles in measured
area seems to be random
• Particles: about 1% of measured area
• Might be intentional, anti-stitch agent
Total image area
1.6mm x 1.6mm, 62500 spectra
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2441327
Total feature area
18746
Feature area
percentage
0.77%
Summary
Nicolet Continuum
Infrared spectral purity and superlative optical microscopy
Nicolet iN10 and iN10MX
Infrared performance for opaque samples and top speed imaging
DXR Dispersive Raman Microscope
Highest spatial resolution and sensitivity to crystallinity / morphology
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