A Full Exploitation of the Pulsed Laser Polymerization Technique to Assess All Important Rate Coefficients in Acrylate Radical Polymerization

Transcription

1 A Full Explitatin f the Pulsed Laser Plymerizatin Technique t Assess All Imprtant Rate Cefficients in Acrylate Radical Plymerizatin Yshi Marien, 1 Paul Van Steenberge, 1 Katrin Kckler, 2 Christpher Barner-Kwllik, 2,3 Marie-Françise Reyniers, 1 Dagmar D'hge, 1 and Guy B. Marin 1 1 Labratry fr Chemical Technlgy (LCT), Ghent University Labratry fr Chemical Technlgy, Ghent University 2 Preparative Macrmlecular Chemistry, Karlsruhe Institute f Technlgy (KIT) 3 Schl f Chemistry, Physics and Mechanical Engineering, Queensland University f Technlgy (QUT)

2 AIChE Annual Meeting, San Francisc, Nvember 13, 2016 Principle f PLP Laser pulse k p [M] 0 units per secnd Laser pulse t = 0 s 0 < t < Δt t = Δt Δt < t < 2Δt 1 macrradical type L j = (k p [M] 0 Δt) j = 1, 2, j A. Aleksandrv, V. N. Genkin, M. Kitaĭ, I. Smirnva and V. Sklv, Sv. J. Quantum Electrn., 1977, 7, O. F. Olaj, I. Bitai and F. Hinkelmann, Macrml. Chem. Phys., 1987, 188,

3 AIChE Annual Meeting, San Francisc, Nvember 13, 2016 Practical use f PLP Size exclusin chrmatgraphy (SEC) analysis k p = L j [M] 0-1 (jδt) -1 ; j = 1, 2, 3

4 AIChE Annual Meeting, San Francisc, Nvember 13, 2016 Backbiting in acrylate PLP k p,app = k p,e k bb key parameter: rate retardatin shrt-chain branches k p,app = f(k p,e, k p,m, k bb ) N. Nikitin, R. A. Hutchinsn, M. Buback and P. Hesse, Macrmlecules, 2007, 40, B. Wenn and T. Junkers, Macrml. Rapid Cmmun., 2016, 37,

5 AIChE Annual Meeting, San Francisc, Nvember 13, 2016 Outline Methd fr the reliable estimatin f k bb Principle and advantages In silic validatin Applicatin t PLP f n-butyl acrylate Detailed analysis f the SEC trace Mdel validatin & visualizatin f the chain grwth pattern Imprtance f the phtdissciatin parameter Imprtance f the chain initiatin reactivity Imprtance f the terminatin reactivity Cnclusins 5

6 AIChE Annual Meeting, San Francisc, Nvember 13, 2016 Principle and advantages Equatin Bulk (Φ S = 0) Slutin (Φ S = 0.75) τ e [s] τ m [s] 1 k bb k p,m (1 Φ S )[M] 0,bulk Φ S = 0 Φ S = 0.75: factr 4 increase in the average MCR lifetime Variatin f Φ S allws t imprve the sensitivity tward k bb 6

7 AIChE Annual Meeting, San Francisc, Nvember 13, 2016 In silic validatin Regressin t simulated k p,app data (k bb input = 1000 s -1 ) superimpsed with an artificial randm errr (Gaussian sampling with a standard deviatin σ) σ = 400 L ml -1 s -1 (ca. 10%) σ = 800 L ml -1 s -1 (ca. 20%) Estimate: k bb = 1007 ± 157 s -1 Estimate: k bb = 967 ± 262 s -1 Even fr a very large experimental errr the methd is still very accurate Y. W. Marien, P. H. M. Van Steenberge, K. B. Kckler, C. Barner-Kwllik, M.-F. Reyniers, D. R. D hge and G. B. Marin, Plym. Chem., 2016, DOI: /c6py01468b. 7

8 AIChE Annual Meeting, San Francisc, Nvember 13, 2016 Applicatin t PLP f nbua T = 303 K Slvent: butyl prpinate (Φ S = 0, 0.5, 0.75) [DMPA] = ml L -1 E pulse = J k bb = 171 ± 21 s -1 (95% cnfidence interval) F = 1084 >> F tab = 4.84 Y. W. Marien, P. H. M. Van Steenberge, K. B. Kckler, C. Barner-Kwllik, M.-F. Reyniers, D. R. D hge and G. B. Marin, Plym. Chem., 2016, DOI: /c6py01468b. 8

9 AIChE Annual Meeting, San Francisc, Nvember 13, 2016 Outline Methd fr the reliable estimatin f k bb Principle and advantages In silic validatin Applicatin t PLP f n-butyl acrylate Detailed analysis f the SEC trace Mdel validatin & visualizatin f the chain grwth pattern Imprtance f the phtdissciatin parameter Imprtance f the chain initiatin reactivity Imprtance f the terminatin reactivity Cnclusins 9

10 AIChE Annual Meeting, San Francisc, Nvember 13, 2016 Mdel validatin 306 K 325 K [R 0 ] = 2Φ E pulseλ hcn A V [1 exp 2.303ε I 2 L ] Different chain initiatin reactivity DMPA radical fragments Chain length dependent terminatin kinetics (cmpsite k t mdel) Y. W. Marien, P. H. M. Van Steenberge, C. Barner-Kwllik, M. F. Reyniers, D. R. D'hge and G. B. Marin, Macrmlecules, 2016 (submitted). 10

11 AIChE Annual Meeting, San Francisc, Nvember 13, 2016 Hidden infrmatin in the SEC trace n chain initiatin DMPA typical phtinitiatr T 325 K DMPA Benzyl radical k ini 0 L ml -1 s -1 Dimethxy benzyl radical k ini = 0 L ml -1 s -1 inhibiting effect M. Buback, M. Busch and C. Kwllik, Macrml. Thery Simul., 2000, 9, H. Fischer, R. Baer, R. Hany, I. Verhlen and M. Walbiner, J. Chem. Sc.-Perkin Trans. 2, 1990, C. Barner-Kwllik, P. Vana and T. P. Davis, J. Plym. Sci. Pl. Chem., 2002, 40, Z. Szablan, T. M. Lvestead, T. P. Davis, M. H. Stenzel and C. Barner-Kwllik, Macrmlecules, 2007, 40,

12 AIChE Annual Meeting, San Francisc, Nvember 13, 2016 Hidden infrmatin in the SEC trace n terminatin Diffusinal limitatins RAFT-CLD-T technique PLP: lw cnversins Cmpsite k t mdel: k t app i, i = k t app 1,1 i α S k t app i, i = k t app 1,1 i c α S +α L i α L i i c i > i c P. Derbven, D. R. D'hge, M.-F. Reyniers, G. B. Marin and C. Barner-Kwllik, Macrmlecules, 2015, 48,

13 AIChE Annual Meeting, San Francisc, Nvember 13, 2016 Visualizatin f the chain grwth pattern 13

14 AIChE Annual Meeting, San Francisc, Nvember 13, 2016 Outline Methd fr the reliable estimatin f k bb Principle and advantages In silic validatin Applicatin t PLP f n-butyl acrylate Detailed analysis f the SEC trace Mdel validatin & visualizatin f the chain grwth pattern Imprtance f the phtdissciatin parameter Imprtance f the chain initiatin reactivity Imprtance f the terminatin reactivity Cnclusins 14

15 AIChE Annual Meeting, San Francisc, Nvember 13, 2016 Imprtance f Δ[R 0 ] Negligible effect n psitin inflectin pint Strng effect n peak intensities Δ[R 0 ] >>: cnsistency check nt pssible ml L ml L ml L -1 Design f PLP experiments: 1. Identificatin crrect rder f magnitude Δ[R 0 ] 2. Selectin adequate values fr E pulse and [I 2 ] via: [R 0 ] = 2Φ E pulseλ hcn A V [1 exp 2.303ε I 2 L ] 15

16 AIChE Annual Meeting, San Francisc, Nvember 13, 2016 Imprtance f the chain initiatin reactivity Assuming equal chain initiatin reactivity: Cnversin is verestimated A less distinct secnd peak is btained, unfavrable fr k p determinatin DMPA is an ideal phtinitiatr due t its nn-ideal character Y. W. Marien, P. H. M. Van Steenberge, C. Barner-Kwllik, M. F. Reyniers, D. R. D'hge and G. B. Marin, Macrmlecules, 2016 (submitted). 16

17 AIChE Annual Meeting, San Francisc, Nvember 13, 2016 Imprtance f the chain initiatin reactivity (2) Inhibitin accunted fr Inhibitin neglected 17

18 AIChE Annual Meeting, San Francisc, Nvember 13, 2016 Imprtance f CLD-T kinetics Experiment k t app i, i = k t app 1,1 i α S i i c k t app i, i = k t app 1,1 i c α S +α L i α L i > i c k t app i, i = k t app 1,1 i α L k t app i, i = k t app 1,1 i α S k t app i, i = k t app 1,1 (Parameters : α S = 0.85, α L = 0.16, i c = 30)i c = 30) N CLD-T and single α (α L ) leads t an verestimatin the lwer chain lengths Single α (α S ) leads t an verestimatin f the higher chain lengths Only the cmpsite mdel yields a gd fit with the experimentally recrded MMD C. Barner-Kwllik, F. Gunzler and T. Junkers, Macrmlecules, 2008, 41, J. Barth, M. Buback, P. Hesse and T. Sergeeva, Macrmlecules, 2010, 43,

19 AIChE Annual Meeting, San Francisc, Nvember 13, 2016 Cnclusins Methd fr the reliable estimatin f k bb Lw frequency k p,app data less expensive PLP equipment Variatin f Φ S high sensitivity tward k bb In silic validatin + successful applicatin t PLP f nbua Detailed analysis f the SEC trace Measured SEC traces accurately simulated Disparate reactivities DMPA radical fragments cnfirmed and shwn t be beneficial Validity f mdels fr apparent terminatin rate cefficients tested at lw mnmer cnversins 19

20 AIChE Annual Meeting, San Francisc, Nvember 13, 2016 Acknwledgements Lng Term Structural Methusalem Funding by the Flemish Gvernment Interuniversity Attractin Ples Prgram Belgian State Belgian Science Plicy Fund fr Scientific Research Flanders (FWO; G N) STN prgram f the Helmhltz assciatin (Karlsruhe Institute f Technlgy) 20