Institute for Polymer Research Symposium May 10, Waterloo, Ontario. Ahmad Alshaiban and João B. P. Soares

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Symposium May 10, 2011 University it of Waterloo Waterloo, Ontario Ahmad Alshaiban and

1 Propylene Polymerization using Ziegler-Natta Catalysts Mathematical Modeling, Polymerization Kinetics and Polymer Characterization Study Institute for Polymer Research Symposium May 10, 2011 University it of Waterloo Waterloo, Ontario Ahmad Alshaiban and João B. P. Soares Department of Chemical Engineering g University of Waterloo Waterloo, Ontario, Canada

2 Outline Background Polypropylene Ziegler-Natta Catalysts and Electron Donors Results Modeling Polymerization : Kinetic Reactor Setup Estimation of Kinetic Constants Polymerization : Characterization Molecular Weight / GPC Tacticity / 13 C NMR Crystallinity / CEF Conclusions 2

3 Polypropylene Background Propylene CH 3 CH CH2 Isotactic Atactic Syndiotactic CH CH 3 CH 3 CH 3 CH 3 CH 3 CH CH CH CH CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 3 CH 3 CH 3 CH 3 CH 3 CH CH CH CH CH CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 3 CH 3 CH 3 CH 3 CH 3 CH CH CH CH CH CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 3

4 Ziegler Natta Catalyst Background Electron Donor Functionality Low isotactic Ti Mg Cl Donor :D Donor :D Vacancy :D Inactive Polymer :D Atactic Highly isotactic Ti Mg Cl Vacancy Polymer Active site models for MgCl 2 TiCl 4 (Kakugo et al., 1988) 4

5 Isotacticity and MWD Background Polypropylene tacticity and MWD have a significant effect on its properties. Electron donors control polypropylene tacticity. (Chadwick et al, 2001) 5

6 Modeling Results Mathematical Modeling 6

7 Modeling Modeling Results Site Transformation: Electron Donor D D Atactic isotactic Ti Mg Cl Vacancy Polymer Propagation: Ti + Ti Termination: Ti + H H Ti H + P p R p R p R tr R tf P tr R p R tr R tr R tf P tf R p R tf R tr R tf 7

8 Dynamic Solution Simulation Modeling Results eight (g/mol) Molecular W x 10 M w M n 4 Overall : Molecular l Weights vs. Time Normal Conditions 2 [Do] 2 [H 2 ] 2 [M] Time "Sec" " x 10 4 A. Alshaiban and J. B. P. Soares, Macromol. Symp., 285, 8 (2009) 8 A. Alshaiban and J.B.P. Soares, Macromol. React. Eng., 5, 96 (2011)

9 Monte Carlo Simulations Modeling Results dw / d log(mw) 1.50 I Isotactic i (799%) (79.9 Stereoblock Isotactic (91.5 %) Atactic (13.0 %) 1.50 Isotactic Atactic (2.1 %) Stereoblock Isotactic Stereoblocks (7.1 %) Stereoblocks (6.4 %) 1.00 Atactic log(mw) dw / d log(mw) 1.00 Atactic log(mw) d 0.5 x Do Do 2 x Do A. Alshaiban and J.B.P. Soares, Macromol. React. Eng., 5, 96 (2011) ppm downfield TMS

10 Polymerization Polymerization 10

11 Reactor Set up Polymerization Kinetic Propylene PI FI Cooling Water rpm control TIC PC Cooling Water Elect. Heat Level-1 Level-2 DCPDMS (D-Donor) Di cyclo pentyl di methoxy silane Do/Ti (mol/mol) H 2 (psi) 16 0 T ( o C)

12 Estimation of Kinetic Constants Polymerization Kinetic Propylene Uptake R p, Exp V dm dtt 2 R p k p Mathematical Formulation MC 1 e min k K k p a k d [ R p, Exp R p 0 ] 2 K a k t(1 k 1 d d K K a a ) e k d t V 12 *

13 Polymerization Polymerization Kinetic 60 o C Factor I II III IV Al/Ti (mol/mol) 900 (± 7.1%) 900 (± 16%) 900 (± 7.7%) 900 (± 7.2%) Do/Ti (mol/mol) 1.5 (± 7.1%) (± 9.6%) 0 H 2 (psi) (± 10%) 16 (± 10%) Yield (g PP g cat 1 min 1 ) 7.6 (±15%) 6.1 (±15%) 17.3 (±2.5%) 8.4 (±6.5%) l/min) Rp (mo _I_36 60_I_37 60_I_ Time (min) 13 *

14 Polymerization Polymerization Kinetic mol/min) Rp (m R p Experimental vs. Calculated at 60ºC _I_exp (D, ) 60_II_exp (, )) 60_III_exp 60_IV_exp 60_I_cal 60_II_cal 60_III_cal 60_IV_cal Time (min) (D, H) (, H) 14

15 Polymerization Results mol/min) Rp (m R p Experimental vs. Calculated at 70ºC _I_exp 70_II_exp Time (min) 70_III_exp 70_IV_exp 70_I_cal 70_II_cal 70_III_cal 70_IV_cal (D, ) (, )) (D, H) (, H) 15

16 Polymerization 2 Group II (D, ) min[( Rp Exp Rp ) ( Rp Exp Rp ) min) Rp (mol/ k K k p a k d, 60 C, 60_II_exp 60_II_cal 70_II_exp 70_II_cal Time (min) E kcal/mol o C K a (min) k 1 1 p (L mol 1 min ) 1.7x x o C 70 C ] Polymerization 2 Kinetic k d (min) *

17 Polymerization Polymerization Kinetic Activation Ene ergy (kcal.mo l 1) EA Ep Ed I (D, ) II (, ) III (D, H) IV (, H) 17 *

18 Summary of the Estimated Kinetic Constants Polymerization Kinetic K a increases as T increases. K a increases by adding H 2 in absence of Do. K a get s the highest value at the presence of H 2 only (IV). K p increases as T increases. k p get s the highest value at the presence of Do & H 2 (III). k p increases by adding H 2 (III) & (IV). k d increases as T increases. k d increases by adding H 2 in absence of Do (IV). 18 *

19 Conclusion Conclusion Kinetic Developed a detailed mathematical model that describes propylene polymerization kinetics and polypropylene microstructure, taking in consideration the effect of external electron donors. ( * ) Estimated the activation energies of activation, propagation, and deactivation of a commercial heterogeneous Ziegler Natta catalyst for propylene polymerization in order to be integrated with the commercial process simulator. ( * ) A. Alshaiban and J. B. P. Soares, Macromol. Symp., 285, 8 (2009) A. Alshaiban and J.B.P. Soares, Macromol. React. Eng., 5, 96 (2011) 19

20 Polymerization Characterization GPC Analysis

21 GPC Analysis Polymerization Characterization M n decreases with H 2 at the same T. M n increases with T in the presence of Do and vice versa. PDI decreases with H 2. 2 PDI decreases with increasing T.

22 GPC Analysis Polymerization Characterization dw W/d(log MW) Exp.# Site Types = I (donor, no H 2 ) II (no donor, no H 2 ) III (donor, H 2 ) IV (no donor, H 2 ) Number of Site Type log MW

23 GPC Analysis Polymerization Characterization Parameter I (D, ) II (, ) 60 o C III (D, H) IV (, H) M n (g mol 1 ) 30.1 x x x x 10 3 M w (g mol 1 ) x x x x 10 3 PDI Number of site types (n) Parameter I (D, ) II (, ) 70 o C III (D, H) IV (, H) M 1 94x10 n (g mol ) 84.1 x x x M w (g mol 1 ) x x x x 10 3 PDI Number of site types (n)

24 Polymerization Characterization 13 C NMR Analysis

25 13 C NMR Analysis Polymerization Characterization ppm III (D, H) IV ( H) ppm IV (, H)

Characterization IV (, H) 1 mmmm 22.0.7 83.78 61.25 93.

87 0.00 0.00 4 mmrr.2.0 4.17 7.76 2.48 4.96 5 mmrm + rmrr.

00 0.00 7 rrrr 20.5 20.25 2.90 3.55 0.00 2.61 8 rrrm 20.

26 13 C NMR Analysis Seq.# Range ( d )* I (D, ) II (, ) III (D, H) Polymerization Characterization IV (, H) 1 mmmm mmmr rmmr mmrr mmrm + rmrr rmrm rrrr rrrm mrrm Range of d reported by Busico et al.(2001)

27 13 C NMR Analysis: Simulated H 2 effect on polypropylene tacticity Polymerization Characterization 1/2 x H2 4.28% H 2 2 x H % 6.04% 7.19% 7.45% 3.90% 83.01% 86.77% 88.65% Isotactic chains in wt% Atactic chains in wt% Stereoblock chains in wt% A. Alshaiban, 2008, MASc. Thesis, University of Waterloo A. Alshaiban and J. B. P. Soares, Macromol. Symp., 285, 8 (2009) A. Alshaiban and J.B.P. Soares, Macromol. React. Eng., 5, 96 (2011)

28 Polymerization Characterization TREF CEF Analysis Injection Crystallization Elution F E T i T f T i T f CEF F c F E

29 CEF Analysis Polymerization Characterization dw/d dt (D, ) (, ) A_70_I_158 A_70_I_159 A_70_II_157 A_70_II_147 ( D, H) (, H) A_70_III_154 A_70_III_155 A_70_IV_151 A_70_IV_ Temperature ( o C)

30 CEF Analysis Polymerization Characterization dw W/dT (D, ) (, ) ( D, H) (, H) A_60_I A_60_II A_60_III A_60_IV Temperature ( o C)

31 CEF Analysis C Polymerization Characterization dw/dt dw/dt 15 A60I A_60_I A70I A_70_I C Temperature ( o C) A_60_II A_70_II C C Temperature ( o C) M n g/mol Group I (D, ) PDI mmmm % 30.1 x x M n g/mol Group II (, ) PDI mmmm % 22.5 x x

32 dw/dt dw/dt CEF Analysis C A_60_III A_70_III C Temperature ( o C) A_60_IV A_70_IV C C 5 M n g/mol Group III (D, H) PDI Polymerization Characterization mmmm % 18 x x Group IV (, H) M n PDI mmmm g/mol % 19 x x Temperature ( o C)

33 Conclusion Conclusion Conducted a systematic polymerization kinetics and microstructural studies for polypropylene produced using 4 th generation ZN catalyst and compared the hydrogen effect with the simulation results obtained from the developed mathematical model. Adding Do increases M n ; and at Do presence, M n increases with T as in groups I (D, ) & III (D,H). M n decreases with H 2 at the same T as we go from II (, ) toiv(, H) and from I (D, ) toiii (D,H) Number of site types decreased by one at high T in the presence of H 2. No significant change in pentad assignments with T except for group I (Do, ) Introducing H 2 tends to increase the tacticity [ I (D, ) III (D,H) ] and [ II (, ) IV (, H) ] which h is in agreement with our simulation of the developed d mathematical ti model. Group III (D, H) shows the highest crystallization peak temperature. Crystallinity increases with T in the presence of Do, I (D, ) &III (D,H). A. Alshaiban and J. B. P. Soares, Macromol. Symp., 285, 8 (2009) A. Alshaiban and J. B. P. Soares, Macromol. Symp., Accepted A. Alshaiban and J. B. P. Soares, Macromol. React. Eng., 5, 96 (2011)

34 The End

IPR By: Supervised By: Institute t for Polymer Research, Department tof fchemical Engineering University of Waterloo

IPR By: Supervised By: Institute t for Polymer Research, Department tof fchemical Engineering University of Waterloo Active Site Identification and Mathematical Modeling of fp Polypropylene l Made with Ziegler-Natta Catalysts By: Ahmad Alshaiban Supervised By: Prof. João B.P. Soares Institute t for Polymer Research,