Radical (Co)polymerization Kinetics Obtained From Droplet-Based Microfluidics

Radical (Co)polymerization Kinetics Obtained From Droplet-Based Microfluidics Emmanuel MIGNARD Patrick MAESTRO CNRS / UMR5258 LOF December 4, 214 Atelier de Prospective du GFP - Intensification des procédés liés aux polymères

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 July 16, 29 EPF 9 - European Polymer Congress 29 - Graz, Austria 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? At small length scales, transport phenomena can be precisely controlled: Mixing - Thermal transfers - Concentrations - Flows 3

Radical Copolymerization Kinetics Obtained From Droplet-Based Microfluidics Size of the reactor Mass & heat transfer mm 4

Lab Tools: Droplet-Based Microfluidics Importance of the size of the microreactor micro milli batch 5 µm 5 µm 1 mm 19 cm.3 nl.3 µl 3 µl 3 L Flow-rates.1 ml/h 2 ml/h 6 ml/h - Surface/Volume 3 3 15 1 Residence time 3 s 1 h > h > h Mixing time 1-6 ms.4-1.5 s 3-1 s 6 s Reactions fast slow sampling exothermic ++ + - - - + ++ ++ - - ++ + ++ ++ ++ - 5

Droplet-Based Microfluidics Microfluidics : a miniaturized continuous approach Oil A B 5 µm Oil Sarrazin et al. 26 Droplets independent chemical microreactors Analysis = inline monitoring in real time by using non-intrusive techniques Control of flows/mixing Control of concentrations Compartmentalization Transparency Sequential production Control of residence times Microscope, Mixing inside spectroscopy, by wall forced IR Thermography convection Potential Management for High of Throughput viscosity issues Experiments Very high S/V ratio Favors heat exchange Temporal resolution Time/space correspondence Small volumes Ideal tool for kinetic Improve data safety, acquisition less waste 6

Droplet-Based Microfluidics Low cost & user-friendly Droplet-Based Micro- or Millifliduics Tubing FEP 1/8 OD & 1/16 ID 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 7

Coupling inline analytical tools Raman (back scattering) Identification Conversions Heating device Cylindre chauffant Probe -2-1 1 Passage du laser 2 Tube FEP 1/8 Mixing by Raman imaging (false colors) 1 2 3 Thermal Infra-Red CCD Heat of reaction Spectroscopy UV-Vis Turbidity (frequency of droplets) Absorption 8

Coupling inline analytical tools For a qualitative determination OceanOptics Laser: 532nm, 5mW $ InPhotonics probe Optical fiber: polyurethane, length: 5m, Ø: 2µm Material: stainless steel and quartz Backscattering Focus distance: about 7,5mm OceanOptics QE65 Spectrometer Resolution: 18cm -1 Software: SpectraSuite USB Possible sample holder 9

Coupling inline analytical tools In depth quantitative analysis by Raman spectroscopy Laser NdYAG 632 nm, 5mW Doubled frequency $$$ Olympus BXFM Microscope: Objectives: x1 ; x5 ou 1x Backscattering Jobin-Yon LABRAM HR8 Spectrometer Resolution: 1 cm -1 Software: Labspec Motor drive control of x-y-z table Possible sample holder 1

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 July 16, 29 EPF 9 - European Polymer Congress 29 - Graz, Austria 11

Monitoring of acrylic acid polymerization intensité Raman scattering Experimental set-up Aqueous phase Fluorous oil Generation of droplets Calibration based on Raman spectroscopy 12 1 8 solution 3 solution 5 solution 7 solution 9 solution 1 Calibration @ 164 cm -1 and @ high temperature 6 4 2 16 164 168 172 176 18 Raman shift (cm-1) Concentration of AA (%) 12

Monitoring of acrylic acid polymerization Experimental set-up 13

Absorbance Units 5 1 15 2 25 Absorbance Units Absorbance Units Absorbance Units 5 1 15 2 25 5 1 15 2 25 5 1 15 2 25 C:\Documents and Settings\nlorber\Mes documents\doc Thèse\PAA\Tufu cylindrique\9nlr1112-3 PAA4%R2T8 C\t.txt Monitoring of acrylic acid polymerization Absorbance Units 5 1 15 2 25 Counts Conversion Droplets allow using the time vs space correspondence 2.5 1 4 1 2 1 4.8 1.5 1 4.6 1 1 4.4 158 159 16 161 162 163 164 165 166 167 158 159 16 16 161 161 162 163 163 164 164 165 166 166 167 158 159 165 167 5.2 C:\Documents C:\Documents and Settings\nlorber\Mes and Settings\nlorber\Mes documents\doc Thèse\PAA\Tufu cylindrique\9nlr1112-3 PAA4%R2T8 C\t5.txt PAA4%R2T8 C\t.txt Seite 1 von 1 C:\Documents and Settings\nlorber\Mes documents\doc Thèse\PAA\Tufu cylindrique\9nlr1112-3 PAA4%R2T8 C\t5.txt Seite 1 von 1 Seite 1 von 1 5 1 15 2 25 3 35 16 162 164 166 168 17 Time (s) Raman shift (cm -1 ) 1 residence time 1 position Monomer conversion with time 158 159 16 161 158 162 159 163 16 164 161 165 162 166 163 167 164 165 166 167 1 information 14

Monitoring of acrylic acid polymerization Conversion Kinetics n HO O Na 2 S 2 O 8 H 2 O, ph = 2.5 * HO n O * Conversion: n 1 n m, t m, C 1 C m, t m, Polymerization rate: -2 R p I I 1 164cm t 1 164cm AA fk I d d 2 k p dt k t I I [AA] 1 15cm t 1 15cm 1.8.6 [AA] = 2.8 mol.l -1 (2 wt. %) ph = 1.8 ; 81 C ln R p, -2.5-3 -3.5 y = -4.9841 + 1.3441x R 2 =.98648 y = -1.8318 +.5156x R 2 =.99441.4.2 [ I 2 ] (mol.l -1 ) [AA]/[I]=225,125 [AA]/[I]=1,28 [AA]/[I]=5,56 [AA]/[I]=25,112-4 -4.5 5 1 15 2 25 3 35 Temps Time (s) (s) -5-5 -4-3 -2-1 1 2 ln [NaPS] ou ln [AA] Macromolecules, 43 (21) 5524 Macromolecular Symposia, 296 (21) 23 15

Monitoring of acrylic acid polymerization Conversion Na Kinetics 2 S 2 O 8 * n HO O H 2 O, ph = 2.5 HO n O * Conversion: n 1 n m, t m, C 1 C m, t m, I I 1 164cm t 1 164cm I I 1 15cm t 1 15cm 1 [AA] = 2.8 mol.l -1 (2 wt. %) ph = 1.8 ; [I 2 ] =.28 mol.l -1 Overall activation energy of the poly rate: Ln R p, E ln( R ) A a p, ln RT -1.5 Ln Rp, (4%) -2 Ln Rp, (2%) -2.5 Ea = 82 kj.mol -1-3 -3.5 Ea = 8 kj.mol -1,8,6,4,2 T C 68 C 74 C 81 C 86 C 9 C -4-4.5 y = 25.399-9.8893x R 2 =.99568 y = 23.414-9.5637x R 2 =.9868-5 2.7 2.75 2.8 2.85 2.9 2.95 1/T x 1 3 ( K -1 ) 1 2 3 4 5 6 7 Time Temps (s) (s) Macromolecules, 43 (21) 5524 Macromolecular Symposia, 296 (21) 23 16

Monitoring of the copolymerization Raw Raman spectra from monomers Water spectra in the interest area (zoom) 1. Baseline 2. Deconvolution 3. Calibration 4. Test 5. Validation Smooth Internal reference Water 17

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 1597-162 cm -1 1628-1633 cm -1 3. Calibration 4. Test 5. Validation 19

Monitoring of the copolymerization Validation of the calibration 1. Baseline SSNa Temperature 23 C 7 C 8 C 1597-162 cm -1 3,21 ±,2 3,68 ±,6 3,6 ±,6 1628-1633 cm -1 3,27 ±,2 3,67 ±,6 3,53 ±,5 AA 2,1 ±,6 1,65 ±,3 1,61 ±,5 P(NaSS),71 ±,1,84 ±,3,8 ±,2 2. Deconvolution 3. Calibration 4. Test 5. Validation Simulations with model solutions AA + NaSS NaSS+ P(NaSS) AA n (cm -1 ) 2

Monitoring of the copolymerization Assume terminal model of copolymerization: k 11 --M 1 * + M 1 ---M 1 * k 21 --M 2 * + M 1 ---M 1 * k 12 --M 1 * + M 2 ---M 2 * k 22 --M 2 * + M 2 ---M 2 * d M 1 = k dt 11 M 1 M 1 + k 21 M 2 M d M 1 = M 1 r 1 M 1 + M 2 1 d M 2 M 2 M 1 + r 2 M 2 d M r 1 2 = k 11 et r = k 2 = k 22 k 12 dt 12 M 1 M 2 + k k 22 21 M 2 M 2 21

Monitoring of the copolymerization [AA] = 2.8 mol.l -1 (2 wt. %) ; ph = 1.8 ; 7 C AA / NaSS = 8 / 2 (wt. % ratio) Time (s) Time (s) 22

F(f-1)/f Monitoring of the copolymerization B A Data 1 C Data 2,1,5 1 1 2 8 η -,1 -,2 -,5 -,1 1 8 Data 35 6 y = -,78845 + 1,2798x R 2 =,99964 4 y = -1,384 +,8935x R 2 =,99615 F(f-1)/f -,15 2 -,3 Kelen-Tüdos -,4,5,1,15,2,25 ξ 6 -,2 4 -,25-2,2,4,6,8,1,12,14 2 Fineman-Ross F²/f r AA = k 11 k 12 r SSNa = k 22 k 21 Droplet-based microfluidics.26 2.1 Wiley et al. (1958). 2 4.5-2 Drift in composition with residence time 1 2 3 4 5 6 7 8 - NaSS - AA Time Grabiel et Decker (1962).1 1. 23

Conclusion and outlooks 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 Molecular weights with residence time by off-line SEC 24

Thanks to CNRS LOF: Dr. Nicolas Lorber Ousmane Savané Daniel Subervie Solvay LOF: Dr. Pierre Guillot Dr. Flavie Sarrazin Thank you for your attention! Solvay RIC-Paris: Dr. James Wilson Bordeaux IPREM UPPA: Dr. Oihan Garagalza Dr. Bruno Grassl Dr. Stéphanie Reynaud December 4, 214 Atelier de Prospective du GFP - Intensification des procédés liés aux polymères