Chemical Composition and Microstructure Analysis of Complex Polymers by Multidimensional Liquid Chromatography

Transcription

1 Chemical Composition and Microstructure Analysis of Complex Polymers by Multidimensional Liquid Chromatography 1 arald Pasch, Khumo Maiko, Pritish Sinha SASOL Chair of Analytical Polymer Science Department of Chemistry and Polymer Science Wolf iller, Mathias ehn Faculty of Chemistry Technical University Dortmund, Germany

2 Stellenbosch South Africa Darmstadt 2

3 Molecular eterogeneity of Complex Polymers äufigkeit Chain length Chain Length SEC Functionality Type End Group LCCC * C 3 3 COOC 3 COOC C 3 3 COOC C 3 * Isotactic Chemical composition Block Length Molecular topology Architecture * * Atactic LAC 3 C COOC 3 3 C COOC 3 3 COOC C 3 * * Syndiotactic Molar Mass 3 C COOC 3 3 COOC C 3 3 C COOC 3 2 * C C C C C C C * 2 2 D 2 D D D D * C C C C C C C * D 2 D 2 D D D D D D D D D D D D D D D D D D D D 3 Isotopic composition vs. D

4 Liquid Chromatography of Polymers S S S S S S Pore in stationary phase Example: column: Nucleosil Si 100 mobile phase: TF / exane 80:20 PS PVAc PMMA S injection solvent Log M SEC LC-CC Gradient LAC 4 Elution volume or K d

5 5 The LEGO Approach

6 Comprehensive 2D-LC for Maximum Selectivity 6

7 Functional Polyethylene Oxides Alk( Ar) O + O Alk(Ar) (OC 2 C 2 )n O secondary reactions additional functionality fractions (OC 2 C 2 )n O Alk(Ar) (OC 2 C 2 )n OAlk(Ar) Dispersants Emulsifiers Paper chemicals (OC 2 C 2 )n Molar mass distribution Functionality type distribution Amount of cyclics Washing formulations Body care 7

8 Functional Polyethylene Oxides Functionality separation by LC-CC Oligomer Separation by LAC stationary phase: RP-18 stationary phase: Si mobile phase: MeO-water 80:20 mobile phase: i-pro-water 88:12 C n 2n+1 O(C 2 C 2 O) x C n 2n+1 O(C 2 C 2 O) x 100 C Nonylphenyl C 13 C PEG C 12 C 14 C 15 C 16 Detector Signal Elution Volume (ml) Endgroup selectivity Elution Volume (ml) Chain length selectivity 8 J.-A. Raust, A. Bruell, P. Sinha, W. iller,. Pasch. J. Sep. Sci. 33 (2010) 1-7

9 2D Chromatography PLC vs. SEC 1. Dimension: PLC/LCCC Degasser Pump Injector 2. Dimension: GPC PLC Column Data Processing Degasser Pump SEC Column Detector Waste 9

10 Functional Polyethylene Oxides Endgroup and oligomer separation by 2D-LC (LC-CC x LAC) Endgroup Length Oligomer Length C O(C 2 C 2 O) C 10 C 9 Φ C 12 C 13 C 14 C 15 C 16 C J.-A. Raust, A. Bruell, P. Sinha, W. iller,. Pasch. J. Sep. Sci. 33 (2010) 1-7

11 Functional Polyethylene Oxides Quantification of oligomer distributions and topology of endgroups by 2D-LC (LC-CC x LAC) 1 -NMR LC-CC 1 -NMR for topology of endgroups LAC 1 -NMR for oligomer distributions 11 W. iller, M. ehn, P. Sinha, J. Raust,. Pasch. Macromolecules 45 (2012)

12 Functional Polyethylene Oxides Quantification of oligomer distributions and topology of endgroups by 2D-LC (LC-CC x LAC) 1 -NMR 12 W. iller, M. ehn, P. Sinha, J. Raust,. Pasch. Macromolecules 45 (2012)

13 13 Separation According to Isotope Effects and Microstructure

14 Separation of PS by Degree of Deuteration d-ps h-ps h-ps d-ps LCCC LAC SEC LCCC 41 o C 54 o C d-ps h-ps V R = V i + V K d SEC LAC K d = exp ( S/R - /RT) stationary phase: Nucleosil C Å mobile phase: TF-ACN 14 47:53 v/v 45 o C P. Sinha, G. arding, K. Maiko,. Pasch, J. Chromatogr. A 1265 (2012)

15 Separation of PS by Degree of Deuteration Separation of similar molar masses and chemical structures the only difference being the deuteration 15 P. Sinha, G. arding, K. Maiko,. Pasch, J. Chromatogr. A 1265 (2012)

16 Microstructure Analysis of PMMA ELSD Response ELSD Response Vertical cut of 2D (SGIC) Vertical cut of 2D (SGIC) Syndio Syndio 4900 (S3) 4900 (S3) Syndio (S4) Iso 4890 (I1) ELSD Response ELSD Response orizontal cut of 2D (SEC) orizontal cut of 2D (SEC) Syndio 4900 (S3) Syndio Iso 4890 (S4) (I1) Syndio 4900 (S3) Elution Elution volume volume (ml) (ml) Elution Elution volume volume (ml) (ml) LC x LC: injection volume: 50µL 1 st Dimension conditions: ypercarb (150mmx4.6mm), 30 C; Flow rate: ml/min (387 min); mobile phase: DCM/acetone gradient 2 nd Dimension conditions: PL Mixed E (300mmx7.5mm); 25 C; loops :200µL; Flow rate: 2mL/min (4.5min); Detection: ELSD K. Maiko, M. ehn, W. iller,. Pasch, Anal. Chem. 85 (2013)

17 Microstructure Analysis of PMMA ELSD Signal SGIC Elution volume (ml) ELSD Signal SEC Elution volume (ml) K. Maiko, M. ehn, W. iller,. Pasch, Anal. Chem. 85 (2013)

18 yphenation of Selective Separations with Spectroscopic Methods 18

19 On-flow-Coupling of PLC and 1 -NMR NMR Console AVANCE 400 Magnet 400 Mz AGILENT 1100 PLC System On-Flow Pump Sampler Loop collector 5mm NMR tube rf coils Flow cell rf coils Detector Waste 19

20 PLC-NMR Coupling: Experimental Challenges styrene-ethylacrylate copolymer Solvent mixture TF-ACN Use of protonated solvents: overlapping of polymer and solvent signals Efficient solvent suppression techniques! Use of PLC quality solvents: Solvent impurities cause strong signals Solvents with NMR purity! 20

21 Microstructure Analysis of Polyisoprene C 3 R 1 C 2 C R 2 n C C 2 1,2-PI C 3 R 1 C 2 C C C 2 R 2 n 1,4-PI R 1 C 2 C R 2 n C C 3 2 C 3,4-PI LCCC of 1,4-PI mobile phase: butanone/cyclohexane 70:30, 92:8, 97:3 stationary phase: 3 x C 18 (100-5, 300-5, ) 21 W. iller, P. Sinha, M. ehn,. Pasch, T. ofe. Macromolecules 44 (2011)

22 Microstructure Analysis of Polyisoprene: LCCC-NMR On-flow LCCC-NMR of blend of 1,4-PI (20.7 kg/mol) and 3,4-PI (72.8 kg/mol) at critical conditions of 1,4-PI, 100 µl injection, flow rate 0.5 ml/min Normalized NMR intensities and chemical composition distributions of 1,2-, 1,4- and 3,4-isoprene units 22 W. iller, P. Sinha, M. ehn,. Pasch, T. ofe. Macromolecules 44 (2011)

23 Microstructure Analysis of PI-PMMA Block Copolymers. LCCC for PMMA stationary phase: Nucleosil Si Si mobile phase: ethyl acetate LCCC for PI stationary phase: Nucleosil C mobile phase: 1,4-dioxane In both cases single mobile phases, adjustment of critical conditions through temperature variations 23 W. iller,. Pasch, P. Sinha, T. Wagner, J. Thiel, M. Wagner, K. Müllen Macromolecules 43 (2010)

24 Microstructure Analysis of PI-PMMA Block Copolymers PMMA (M p =22700) 1,4-PI (M p =95000) 1,4-PI (M p =20500) PMMA (M p =22700) Separation of PMMA-PI blends at critical conditions for PMMA (left) and PI (right) 24 W. iller,. Pasch, P. Sinha, T. Wagner, J. Thiel, M. Wagner, K. Müllen Macromolecules 43 (2010)

25 Microstructure Analysis of PI-PMMA Block Copolymers PI omopolymer Copolymer Separation of 3,4-PI-PMMA copolymer (52 kg/mol) at critical conditions for PMMA (left) and PI (right) 25 W. iller,. Pasch, P. Sinha, T. Wagner, J. Thiel, M. Wagner, K. Müllen Macromolecules 43 (2010)

26 Microstructure Analysis of PI-PMMA Block Copolymers Copolymer PI omopolymer Chemical composition analysis of 3,4-PI-PMMA copolymer (52 kg/mol) at critical conditions for PMMA (left) and PI (right) 26 W. iller,. Pasch, P. Sinha, T. Wagner, J. Thiel, M. Wagner, K. Müllen Macromolecules 43 (2010)

27 27 MS as a Detector for Liquid Chromatography

28 Aliphatic Polyesters: Background Paint/Coatings Polymer/Binder Pigments Multi-vesiculated polyester particles 28 Main constituents of UPR: Maleic anhydride Phthalic anhydride Propylene glycol Additives

29 Aliphatic Polyesters: Chemistry Simple monomer structures but complex rearrangements during polymerization äufigkeit Chain Length Chain Length Functional Groups End Group Block Length Architecture Molar Mass 29

30 Aliphatic Polyesters: Molar Mass Analysis by SEC Size exclusion chromatography n = 5 n = 6 n = 7 Fraction 2 Fraction 3 Fraction 4 Fraction 5 n = 3 n = 4 Fraction 6 Fraction 7 n = 2 Fraction 8 30

31 Aliphatic Polyesters: End Group Analysis by SEC-MALDI MALDI-TOF analysis of SEC fractions Chemical structure Abbreviation m/z (exp) values for n O-[PA-PG] n -PA A. O-[PA-PG] n B. C. PG-[PA-PG] n cyclic of [PA-PG] n D. cyclic of PG-[PA-PG] n E.

32 Aliphatic Polyesters: End Group Analysis by PLC Analysis conditions: Stationary phase: SupelcoCN 100Å, 5μm, Mobile phase: TF/exane, Temp: 30⁰C, Flow rate: 1.00 ml/min, Detector: ELSD, Injection vol: 20 μl Normalized ELSD signal peak 0.00 splitting zoomed in Normalized ELSD signal Solvent Gradient PLC s Elution volume (ml) 2 s Elution volume (ml) s Elution volume (ml) % TF Elution volume (ml) Significantly improved separation Oligomer/functional group formation as a function of polymerization time

33 Aliphatic Polyesters: PLC Fractionation and MALDI-ToF 100 %Int C Na C Na C Na C Na C C K C Na K C K B Na C K C K C Na B Na B K CNa C Na B K B Na BNa B K fraction B Na B Na fraction B K fraction 8 fraction fraction fraction 5 %Int Mass/Charge MALDI-ToF spectra of fractions 5 to 11 collected from the gradient elution PLC separation of sample s28 from PA-PG batch B. O-[PA-PG] n -/Na + : m/z 866 (n=4); 1896 (n=9) C. PG-[PA-PG] n -/Na + : m/z 718 (n=3); 2160 (n=10) C Na O C 2 58 Da C Na C K C Na m/z C Na B Na C K C K C K B Na B K B B Na Na C Na B K Fraction fraction B K B K Fraction fraction m/ Mass/Charge z C C 3 Zoomed-in MALDI-ToF MS spectra of fractions 9 to 11 to indicate the presence of an additional oligomeric structure. O Fraction G: PG-PG-[PA-PG] n -/Na + : m/z 1615 (n=7) ; m/z 2218 (n=10)

34 Aliphatic Polyesters: Comprehensive 2D-LC Binary Pump, Degasser PLC system UV Detector 1 st dimension: solvent gradient PLC LC-CC or Gradient-PLC SEC ELSD 2 nd dimension: SEC Quaternary Pump, Degasser PLC system To Waste Oligomer length and endgroups 34

35 Aliphatic Polyesters: SEC-SFC-ESI-QToF ELSD PDA Analysis conditions: Stationary phase: Acquity UPC 2 BE Mobile phase: CO 2 (A) and 1% formic acid in ACN (B). Temp: 30 C, Pressure:150bar. Column SFC of s28 Size exclusion chromatography Sample manager Solvent manager SFC of SEC fraction 2 Supercritical fluid chromatography SFC of SEC fraction 3 SFC of SEC fraction 5 35

36 36 Aliphatic Polyesters: ESI-QToF Analysis of SFC Fractions

37 äufigkeit Chemical Chain length (MMD) Chain Length Block Length composition (CCD) ABBBAAAABB BBBBBAABAA AAAAABBBBB Fractionation of polyolefins does not work at ambient temperatures Molecular topology (MTD) Long End Chain Group Branching Short Chain Branching Architecture LDPE LLDPE DPE TREF Molar Mass 37 Annual production of polyolefins > 100 million tons CRYSTAF

38 Polyolefin Separation by Composition or Microstructure EVAc Copolymers PP by Tacticity Detektorsignal ELSD [V] EVA 5% VA EVA 12% VA EVA 14% VA EVA 19% VA EVA 28% VA EVA 45% VA EVA 50% VA EVA 60% VA EVA 70% VA PVAc-St. 164KD PVAc-St. 32KD PE-St. 126KD PE PVAc 1,0 response 100 of ELSD [Volts] 0, % Cyclohexanon 0,6 0,4 0,2 isotactic PP atactic PP syndiotactic PP Start of gradient linear PE Elutionsvolumen [ml] stationary phase: silica gel mobile phase: gradient of decaline-cyclohexanone 0 0, elution time [minutes] stationary phase: ypercarb mobile phase: gradient of 1-decanol to TCB 38 A. Albrecht, R. Brüll, T. Macko,. Pasch. Macromolecules 40 (2007) 5545 T. Macko,. Pasch. Macromolecules 42 (2009)

39 The LEGO Approach for Polyolefins: T-SEC-FTIR-DSC T-SEC Nebulizer 150 C per DSC Stage: 160 C 39 Vacuum line S. Cheruthazhekatt, T.F.J. Pijpers, G.W. arding, V.B.F. Mathot,. Pasch. Macromolecules 45 (2012)

40 TREF Fractionation of IPC 1. Slow crystallization Controlled cooling IPC: complex mixture of various (E/P) components Dissolved polymer + support (1 C/h) Most crystalline, More crystalline Less crystalline, Least crystalline 2. Elution T 1 T 2 T 3 T 4 T amorphous EP rubber - semi-crystalline EPC?????? - crystalline ipp - app + hpe?????? W i % W i %/ T ipp Increasing temperature Fractionation according to crystallizability W i % EP Rubber Segmented EPC TREF elution temperature (ºC)

41 Impact PP Copolymers (IPC); TREF Fraction at 80 o C complex mixture (1) amorphous EP rubber, (2) semi-crystalline EPC, (3) crystalline ipp, (4) app, (5) hpe 41 S. Cheruthazhekatt, T.F.J. Pijpers, G.W. arding, V.B.F. Mathot,. Pasch. Macromolecules 45 (2012)

42 Impact PP Copolymers (IPC); TREF Fraction at 80 o C V 80 ELSD Response (V) Start of gradient ipp EPC Ethylene rich EPC and PE T-PLC stationary phase: ypercarb Mobile phase: gradient 1-decanol/TCB Elution volume (ml) T-2D-LC 1 st dimension: T-PLC 2 nd dimension: T-SEC in TCB 42 S. Cheruthazhekatt, T.F.J. Pijpers, G.W. arding, V.B.F. Mathot,. Pasch. Macromolecules 45 (2012)

43 Impact PP Copolymers (IPC); TREF Fraction at 130 o C V A C C eat Flow (W/g) C nd eating 1st Cooling C Temperature ( C) 0.2 Linked spectrum at Elution volume 6.3 ml 3V A Absorbance Linked spectrum at Elution volume 3.5 ml Linked spectrum at Elution volume 1.85 ml Wavenumbers (cm -1 )

44 Limitations of SEC/PLC Problems of SEC: Limited towards higher molar masses Shear degradation (mechanical stress due to stationary phase Separation of linear and branched molecules Adsorption on the stationary phase Field Flow Fractionation 44

45 Coupling of FFF and 1 -NMR Temperature Field 45

46 ThFFF-NMR of PI, PS and PMMA Same molar masses but different elution volumes for PI and PS/PMMA Universal calibration ThFFF SEC 46 W. iller, W. van Aswegen, M. ehn,. Pasch, Macromolecules 46 (2013)

47 ThFFF-NMR of Block Copolymers Uniform chemical composition as a function of molar mass Clear indication for fractions of different chemical compositions 47 W. iller, W. van Aswegen, M. ehn,. Pasch, Macromolecules 46 (2013)

48 ThFFF of Block Copolymers x Ph Ph y N O z O B 830 V 180 T g/mol selective towards chemical composition RMS Radius (nm) 48 size Molar Mass (g/mol) Separation according to block copolymer composition based on differences in D T Block D T (cm 2 /s.k) polybutadiene 0.25 x 10-7 Poly(2-vinyl pyridine)? Poly (tert-butyl methacrylate) Still to be determined x 10-7 W. van Aswegen, W. iller, M. ehn,. Pasch, Macromol. Rapid Commun. 34 (2013)

49 Summary Interaction LC is a perfect tool for the chemical composition and microstructure analysis of complex polymers V r Comprehensive 2D-LC provides maximum selectivity regarding chemical composition/microstructure/molar mass separation 2 On-flow LC- 1 -NMR provides microstructure as a function of molar mass or chemical composition igh-temp multidimensional LC has become a feasible tool for polyolefin analysis If LC does not work use field-flow fractionation

50 Multidimensional PLC of Polymers Springer International Publishing Switzerland, 2013 Authors: arald Pasch, Bernd Trathnigg ISBN: (Print) (Online) 50

51 51 Thank you for your attention 51