Radical (Co)polymerization Kinetics Obtained From Droplet-Based Microfluidics
December 04, 2014
Emmanuel MIGNARD Patrick MAESTRO
®CNRS / UMR5258 LOF
Atelier de Prospective du GFP - Intensification des procédés liés aux polymères
Miniaturized tools - Process & Analysis
Introduction
Concept of droplet-based microfluidics for chemistry
Coupling inline analytical tools
Polymerization reactions within droplets
Methodology
Polymerization of acrylic acid
Copolymerization of acrylic acid with Sodium Styrene sulfonate
Conclusion and outlooks
July 16, 2009 EPF’09 - European Polymer Congress 2009 - Graz, Austria
Outline
Miniaturized tools - Process & Analysis
Introduction
Concept of droplet-based microfluidics for chemistry
Coupling inline analytical tools
Polymerization reactions within droplets
Methodology
Polymerization of acrylic acid
Copolymerization of acrylic acid with Sodium Styrene sulfonate
Conclusion and outlooks
2
?
Radical Copolymerization Kinetics Obtained From Droplet-Based Microfluidics
• Microfluidics
The science and technology of systems capable to handle fluids, and where at least one of their characteristic dimensions is of the micrometer
3
At small length scales, transport phenomena can be precisely controlled:
Mixing - Thermal transfers - Concentrations - Flows
≤ mm
Radical Copolymerization Kinetics Obtained From Droplet-Based Microfluidics
Size of the reactor
Mass & heat transfer
4
10 - 60 ms Mixing time
> h > h 1 h 30 s Residence time
- 6 mL/h 2 mL/h 0.1 mL/h
10 1500 3000 30000 Surface/Volume
3 L 3 µL 0.3 µL 0.3 nL
Flow-rates
19 cm 1 mm 500 µm 50 µm
batch milli micro
0.4 - 1.5 s 3 -10 s 6 s
exothermic
fast
slow
sampling
Reactions
++ + - -
- + ++ ++
- - + ++
++ ++ - ++
Lab Tools: Droplet-Based Microfluidics
Importance of the size of the microreactor
5
Microfluidics : a miniaturized continuous approach
Droplets = independent chemical microreactors
Control of flows/mixing Control of concentrations Compartmentalization Control of residence times Mixing inside by wall forced convection Management of viscosity issues Very high S/V ratio Favors heat exchange Temporal resolution Time/space correspondence Small volumes Improve safety, less waste
Sarrazin et al. 2006
A
B
Oil
Oil
Droplet-Based Microfluidics
6
Analysis = inline monitoring in ‘real time’ by using non-intrusive techniques
Transparency Microscope, spectroscopy, IR Thermography Sequential production Potential for High Throughput Experiments
50 µm
Ideal tool for kinetic data acquisition
Low cost & user-friendly Droplet-Based Micro- or Millifliduics
• “Same” microreactors, hydrodynamic properties and possible “inline” analysis
High S/V ratio, space/time correspondence, …
• Higher residence times (about hours)
• Good chemical resistance (PTFE, glass, …)
• Large choice of commercial tubing, capillaries and connectors
• No need of a cleanroom nor expensive microfabrication machines
Tubing FEP 1/8’’OD & 1/16”ID
Droplet-Based Microfluidics
7
• Raman (back scattering)
– Identification
– Conversions
• Thermal Infra-Red CCD
– Heat of reaction
• Spectroscopy UV-Vis
– Turbidity (frequency of droplets)
– Absorption
Tube FEP 1/8’
Cylindre chauffant
Passage du laser
Tube FEP 1/8’
Cylindre chauffant
Passage du laser Probe Heating device
Coupling inline analytical tools
8
1000 2000 3000
-200
-100
0
100
200 0
0.5
1
Mixing by Raman imaging
(false colors)
• OceanOptics Laser: 532nm, 500mW
• InPhotonics probe
– Optical fiber: polyurethane, length: 5m, Ø: 200µm
– Material: stainless steel and quartz
– Backscattering
– Focus distance: about 7,5mm
• OceanOptics QE65000 Spectrometer
– Resolution: 18cm-1
– Software: SpectraSuite
– USB
• Possible sample holder
For a qualitative determination
$
Coupling inline analytical tools
9
• Laser NdYAG
– 632 nm, 500mW
– Doubled frequency
• Olympus BXFM Microscope:
– Objectives: x10 ; x50 ou 100x
– Backscattering
• Jobin-Yon LABRAM HR800 Spectrometer
– Resolution: 1 cm-1
– Software: Labspec
• Motor drive control of x-y-z table
• Possible sample holder
In depth quantitative analysis by Raman spectroscopy
$$$
Coupling inline analytical tools
10
Miniaturized tools - Process & Analysis
Introduction
Concept of droplet-based microfluidics for chemistry
Coupling inline analytical tools
Polymerization reactions within droplets
Methodology
Polymerization of acrylic acid
Copolymerization of acrylic acid with Sodium Styrene sulfonate
Conclusion and outlooks
July 16, 2009 EPF’09 - European Polymer Congress 2009 - Graz, Austria
Outline
Miniaturized tools - Process & Analysis
Introduction
Concept of droplet-based microfluidics for chemistry
Coupling inline analytical tools
Polymerization reactions within droplets
Methodology
Polymerization of acrylic acid
Copolymerization of acrylic acid with Sodium Styrene sulfonate
Conclusion and outlooks
11
Monitoring of acrylic acid polymerization
12
Experimental set-up
Fluorous oil
Aqueous phase
Generation of droplets
0
2000
4000
6000
8000
10000
12000
1600 1640 1680 1720 1760 1800
Raman shift (cm-1)
inte
ns
ité
solution 3
solution 5
solution 7
solution 9
solution 10
0
2000
4000
6000
8000
10000
12000
1600 1640 1680 1720 1760 1800
Raman shift (cm-1)
inte
ns
ité
solution 3
solution 5
solution 7
solution 9
solution 10
Calibration @ 1640 cm-1
and @ high temperature
Concentration of AA (%)
Ram
an s
catt
erin
g
Calibration based on Raman spectroscopy
Monitoring of acrylic acid polymerization
Experimental set-up
13
C:\Documents and Settings\nlorber\Mes documents\DOC Thèse\PAA\Tufu cylindrique\09NLR1112-03 PAA40%R200T80°C\t0.txt
1580 1590 1600 1610 1620 1630 1640 1650 1660 1670
50
00
10
00
015
00
020
00
025
00
0
Ab
sorb
ance
Un
its
Seite 1 von 1
C:\Documents and Settings\nlorber\Mes documents\DOC Thèse\PAA\Tufu cylindrique\09NLR1112-03 PAA40%R200T80°C\t5.txt
1580 1590 1600 1610 1620 1630 1640 1650 1660 1670
50
00
10
00
015
00
020
00
025
00
0
Ab
sorb
ance
Un
its
Seite 1 von 1
C:\Documents and Settings\nlorber\Mes documents\DOC Thèse\PAA\Tufu cylindrique\09NLR1112-03 PAA40%R200T80°C\t0.txt
1580 1590 1600 1610 1620 1630 1640 1650 1660 1670
50
00
10
00
015
00
020
00
025
00
0
Ab
sorb
ance
Un
its
Seite 1 von 1
C:\Documents and Settings\nlorber\Mes documents\DOC Thèse\PAA\Tufu cylindrique\09NLR1112-03 PAA40%R200T80°C\t5.txt
1580 1590 1600 1610 1620 1630 1640 1650 1660 1670
50
00
10
00
015
00
020
00
025
00
0
Ab
sorb
ance
Un
its
Seite 1 von 1 0
5000
1 104
1.5 104
2 104
2.5 104
1600 1620 1640 1660 1680 1700
Cou
nts
Raman shift (cm-1
)
0
0.2
0.4
0.6
0.8
1
0 50 100 150 200 250 300 350
Conve
rsio
n
Time (s)
C:\Documents and Settings\nlorber\Mes documents\DOC Thèse\PAA\Tufu cylindrique\09NLR1112-03 PAA40%R200T80°C\t0.txt
C:\Documents and Settings\nlorber\Mes documents\DOC Thèse\PAA\Tufu cylindrique\09NLR1112-03 PAA40%R200T80°C\t5.txt
1580 1590 1600 1610 1620 1630 1640 1650 1660 1670
50
00
10
00
015
00
020
00
025
00
0
Ab
sorb
ance
Un
its
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1 residence time
1 position Monomer conversion with time
1 information 14
Monitoring of acrylic acid polymerization
Droplets allow using the time vs space correspondence
Monitoring of acrylic acid polymerization
Kinetics
15 Macromolecules, 43 (2010) 5524
Macromolecular Symposia, 296 (2010) 203
**
OOH
n
OH
O
Na2S2O8
H2O,
pH = 2.5
n
1
1
1
1
1050
0
1640
0
1050
1640
0,
,
0,
,11
cm
cm
cm
t
cm
t
m
tm
m
tm
I
I
I
I
C
C
n
n
Conversion:
[AA]0 = 2.8 mol.L-1 (20 wt. %) pH = 1.8 ; 81 °C
0
0.2
0.4
0.6
0.8
1
0 50 100 150 200 250 300 350
[AA]/[I]=225
[AA]/[I]=100
[AA]/[I]=50
[AA]/[I]=25
Con
ve
rsio
n
Temps (s)
y = 1-((((1/3*(M0-m1)*m2)+(2...
ErrorValue
2.01655.6997m1
0.000306380.0069945m2
NA0.0078702Chisq
NA0.99057R2
y = 1-((((1/3*(M0-m1)*m2)+(2...
ErrorValue
1.1124.914m1
0.000386720.01166m2
NA0.0034263Chisq
NA0.99489R2
y = 1-((((1/3*(M0-m1)*m2)+(2...
ErrorValue
0.723997.3965m1
0.000611010.019224m2
NA0.0039064Chisq
NA0.99532R2
y = 1-((((1/3*(M0-m1)*m2)+(2...
ErrorValue
0.653517.2875m1
0.00117060.028942m2
NA0.0053381Chisq
NA0.99328R2
0,0125
0,028
0,056
0,112
Time (s)
[ I2 ]0 (mol.L-1)
-5
-4.5
-4
-3.5
-3
-2.5
-2
-5 -4 -3 -2 -1 0 1 2
y = -4.9841 + 1.3441x R2= 0.98648
y = -1.8318 + 0.5156x R2= 0.99441
ln R
p,0
ln [NaPS]0 ou ln [AA]
0
Polymerization rate:
[AA]k
Ifkk
dt
AAdR
t
d
pp 02
Monitoring of acrylic acid polymerization
[AA]0 = 2.8 mol.L-1 (20 wt. %) pH = 1.8 ; [I2]0 = 0.028 mol.L-1
0
0,2
0,4
0,6
0,8
1
0 100 200 300 400 500 600 700
68°C
74°C
81°C
86°C
90°C
Conve
rsio
n
Temps (s)Time (s)
T °C
16
Kinetics **
OOH
n
OH
O
Na2S2O8
H2O,
pH = 2.5
n
1
1
1
1
1050
0
1640
0
1050
1640
0,
,
0,
,11
cm
cm
cm
t
cm
t
m
tm
m
tm
I
I
I
I
C
C
n
n
Conversion:
Macromolecules, 43 (2010) 5524
Macromolecular Symposia, 296 (2010) 203
Overall activation energy of the poly rate:
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
2.7 2.75 2.8 2.85 2.9 2.95
Ln Rp,0 (40%)
Ln Rp,0 (20%)
y = 25.399 - 9.8893x R2= 0.99568
y = 23.414 - 9.5637x R2= 0.9868
Ln
Rp
,0
1/T x 103 (°K
-1)
Ea = 82 kJ.mol-1
Ea = 80 kJ.mol-1
RT
EAR a
p, ln)ln( 0
Water
Monitoring of the copolymerization
17
Internal reference
Raw Raman spectra from monomers
Water spectra in the
interest area (zoom)
Smooth
1. Baseline 2. Deconvolution 3. Calibration 4. Test 5. Validation
Monitoring of the copolymerization
Corrected Raman spectra from monomers 1. Baseline 2. Deconvolution 3. Calibration 4. Test 5. Validation
Intensity (area) is proportional to the concentration 18
Monitoring of the copolymerization
Validation of the calibration 1. Baseline 2. Deconvolution 3. Calibration 4. Test 5. Validation
19
1597-1602 cm-1 1628-1633 cm-1
Monitoring of the copolymerization
Validation of the calibration 1. Baseline 2. Deconvolution 3. Calibration 4. Test 5. Validation
20
1. Baseline 2. Deconvolution 3. Calibration 4. Test 5. Validation
Temperature 23 °C 70 °C 80 °C
SSNa
1597-1602 cm-1
3,21 ±0,02 3,68 ±0,06 3,6 ±0,06
1628-1633 cm-1
3,27 ±0,02 3,67 ±0,06 3,53 ±0,05
AA 2,01 ±0,06 1,65 ±0,03 1,61 ±0,05
P(NaSS) 0,71 ±0,01 0,84 ±0,03 0,8 ±0,02
n (cm-1)
AA + NaSS
NaSS+ P(NaSS)
AA
Simulations with model solutions
Monitoring of the copolymerization
21
Assume terminal model of copolymerization:
−𝑑 𝑀1
𝑑𝑡= 𝑘11 𝑀1
∗ 𝑀1 + 𝑘21 𝑀2∗ 𝑀1
−𝑑 𝑀2
𝑑𝑡= 𝑘12 𝑀1
∗ 𝑀2 + 𝑘22 𝑀2∗ 𝑀2
--M1* + M1 ---M1
*
--M2
* + M1 ---M1*
--M1
* + M2 ---M2*
--M2
* + M2 ---M2*
k11
k21
k12
k22
−𝑑 𝑀1
𝑑 𝑀2=
𝑀1 𝑟1 𝑀1 + 𝑀2
𝑀2 𝑀1 + 𝑟2 𝑀2
𝑟1 =𝑘11
𝑘12 et 𝑟2 =
𝑘22
𝑘21
Monitoring of the copolymerization
22 Time (s) Time (s)
• [AA]0 = 2.8 mol.L-1 (20 wt. %) ; pH = 1.8 ; 70 °C
• AA / NaSS = 80 / 20 (wt. % ratio)
Monitoring of the copolymerization
23
-0,25
-0,2
-0,15
-0,1
-0,05
0
0,05
-2
0
2
4
6
8
10
0,02 0,04 0,06 0,08 0,1 0,12 0,14
Data 1A C
F(f
-1)/
f
F²/f
-2
0
2
4
6
8
10
0 1 2 3 4 5 6 7 8
Data 35
12
y = -0,78845 + 1,2798x R2= 0,99964
y = -1,3804 + 0,89305x R2= 0,99615
F(f-1
)/f
-0,4
-0,3
-0,2
-0,1
0
0,1
0 0,05 0,1 0,15 0,2 0,25
Data 2
B
η
ξ
Drift in composition with residence time
𝑟𝐴𝐴 =𝑘11𝑘12
𝑟𝑆𝑆𝑁𝑎 =𝑘22𝑘21
Droplet-based microfluidics 0.26 2.10
Wiley et al. (1958) 0. 2 4.5
Grabiel et Decker (1962) 0.1 1.0
Kelen-Tüdos Fineman-Ross
Time - NaSS - AA
Molecular weights with residence time by off-line SEC
Conclusion and outlooks
24
Continuous synthesis of (co)polymers within droplets in a wide range of conditions
Reaction monitoring by Raman confocal microspectrometry
Straightforward data acquisition platform
No manual handling of samples
Data non-accessible in ‘conventional’ batch reactors
Better heat transfer allows performing fast/exothermic reactions
Thank you for your attention! Thanks to
CNRS LOF: Dr. Nicolas Lorber Ousmane Savané Daniel Subervie
Solvay LOF: Dr. Pierre Guillot Dr. Flavie Sarrazin Solvay RIC-Paris: Dr. James Wilson IPREM – UPPA: Dr. Oihan Garagalza Dr. Bruno Grassl Dr. Stéphanie Reynaud
Bordeaux
December 04, 2014 Atelier de Prospective du GFP - Intensification des procédés liés aux polymères