APC Hyphenated to SYNAPT-G2: Potential For The Analysis Of Complex Synthetic Polymers. Marie-Theres Picker Artjom Döring Dirk Kuckling

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1 APC Hyphenated to YAPT-G2: Potential For The Analysis f Complex ynthetic Polymers Marie-Theres Picker Artjom Döring Dirk Kuckling International ymposium on GPC/EC and Related Techniques Amsterdam, 2016

2 University of Paderborn: founded in 1972 currently more than students material science profile in chemistry, physics and mechanical engineering Paderborn 2

3 Research Interests of Prof. Kucklings Working Group: X Controlled Radical Polymerization (MRP, ATRP, RAFT) mart block copolymers for micro heterogeneous organocatalysis or pigment stabilization Y + Z mart Polymers MR IR & UV/VI PR Analytics EC, APC M (MALDI, EI-IM) Free Radical Polymerization and photo cross-linking / photo patterning Hydrogels for applications in biomedicine and as actuators and sensors in micro-system technology mart and biodegradable block copolymers for triggered release systems mart nanohydrogels for targeted transport and controlled release systems Multisensitive phase separated hydrogel layers Receptor/Ligand modified (hydro)gels for sensor applications enzyme 3

4 Applied eparation Techniques ize Exclusion Chromatography (EC) - fractionation of the polymer sample according to the hydrodynamic volume - molecular mass distribution as a result after calibration (relative, universal, absolute) Advanced Polymer Chromatography (APC) - UHP-EC - significantly reduced measurement times and sample concentration - robust porous silica matrix Electron pray Ionization Mass pectrometry (EI-M) - soft vaporization and ionization of macromolecules - separation according to mass/charge ratio - less complicated sample preparation - determination of repeating units and end groups in macromolecules - fairly complex M spectra (mass dispersity, chemical heterogeneity, charge dispersity, mixed ionization) Ion Mobility eparation (IM) - separation of ions with respect to charge, shape and size APC-EI-IM Hyphenation Pacholarz et al., Chem. oc. Rev., 2012, 41,

5 Experimental etup Quadrupole analyzer Triwave collision cell QuanTF analyzer Waters APC Columns: Acquity APC XT 125Å & Acquity APC XT 45Å Eluent: THF/DMF (v/v 80:20) ai (68 µm) Flow rate: 0.7 ml/min Injection volume: 20 µl AI Quickplit Adjustable Flow plitter (ratio approx. 95:5) EI source MALDI source 5

6 Performance of the Waters APC -ystem Eluent: THF/DMF (v/v 80:20), ai (68 µm) DMF as polar solvent for EI ai as ionizing agent no need of secondary pump for addition of make-up solvent and ionizing agent Comparison of APC and EC results revealed ize Exclusion for: PMMA -substituted polyacrylamides (PIPAAm, PDMAAm) Polycarbonates Advanced Polymer Chromatography Columns: Acquity APC XT 125Å & Acquity APC XT 45Å Eluent: THF/DMF (v/v 80:20), ai (68 µm) Flow rate: 0.7 ml/min Injection volume: 20 µl Traditional ize Exclusion Chromatography Columns: P DV (10 6 Å, 10 5 Å, 10 3 Å, 10 2 Å) Eluent: CHCl 3 (0.1 Vol% TEA) Flow rate: 0.75 ml/min Injection volume: 50 µl 6

7 Challenges for the Waters APC -ystem CH m n o co Boc H H source: source: need of modified silica matrices for APC columns polarity fine-tuning is necessary to ensure pure size exclusion without enthalpic interactions 7

8 Complexity of polymer samples Macromolecules exhibit different types of heterogeneity: Distribution of molar mass (monomodal, bimodal etc.) Chemical Composition (copolymers: statistic, gradient, block) Topology (linear, (hyper)branched, dendritic, star, graft, cross-linked) Functionality (end groups, side groups, cyclic) Additionally, mixtures of different polymers can significantly increase sample complexity. Analyzed samples (prepared by RAFT-polymerization) poly(,-dimethylacrylamide)-bpoly(-isopropylacrylamide) with residual amounts of poly(,dimethylacrylamide) homopolymer Mixture of a linear and 4-arm-star homopolymer based on poly(,-dimethylacrylamide) 8

9 Analysis of poly(,-dimethylacrylamide)-b-poly(-isopropylacrylamide) HC n EG EG = HC m n H H M n,apc = 6900 g/mol D = 1.38 AIB 1.4-dioxane, 70 C EG = unreactive (olefine, saturated) M n,apc = 3700 g/mol D = 1.15 HC n EG poly(,-dimethylacrylamide)-bpoly(-isopropylacrylamide) with residual amounts of poly(,dimethylacrylamide) homopolymer 9

10 Analysis of poly(,-dimethylacrylamide)-b-poly(-isopropylacrylamide) with APC-hyphenation without APC-hyphenation EI source Capillary: 3.0 kv ampling cone: 120 V Extraction cone: 3.0 V IM cell Wave length: 550 m/s Wave height: 40 V 10

11 Analysis of poly(,-dimethylacrylamide)-b-poly(-isopropylacrylamide) with APC-hyphenation without APC-hyphenation

12 species 4 with APC-hyphenation species 2 species 1 species 3 without APC-hyphenation number of species? species 4 species 2 species 3 species 1 12

13 species 4 with APC-hyphenation species 2 species 1 species 3 Δm/z = 0.05 Δm/z = 0.05 HC 16 9 H a+ K+ HC 23 3 H a+ a+ 13

14 with APC-hyphenation HC species 4 species 2 species 1 species H a+ K+ M avg, calc = g/mol M avg, found = g/mol C H a+ K+ M avg, calc = g/mol M avg, found = g/mol HC H a+ a+ K+ M avg, calc = g/mol M avg, found = g/mol C H a+ K+ K+ M avg, calc = g/mol M avg, found = g/mol 14

15 Analysis of a mixture of a 4-arm star and a linear homopolymer of poly(,-dimethylacrylamide) RAFT polzmeriyation with a 4-arm trithiocarbonate chain transfer agent PD = 1.13 M n = 4,000 g/mol 1.4-dioxane 70 C M n = 4,400 g/mol PD = 1.06 M Addition of linear n = 4,500 g/mol PD = 1.04 poly(,-dimethylacrylamide) homopolymer m n p + H n o 15

16 Analysis of a mixture of a 4-arm star and a linear homopolymer of poly(,-dimethylacrylamide) with APC-hyphenation without APC-hyphenation EI source Capillary: 3.0 kv ampling cone: 120 V Extraction cone: 3.0 V IM cell Wave length: 550 m/s Wave height: 40 V 16

17 with APC-hyphenation without APC-hyphenation 17

18 Analysis of a mixture of a 4-arm star and a linear homopolymer of poly(,-dimethylacrylamide) with APC-hyphenation contrary tendency compared to linear and star-shaped PEG polymers (Foley et al., AC Macro Lett. 2015, 4, 778) series of triply charged species more expanded structure of the star polymer due to minimizing the electrostatic repulsion 18

19 ummary APC respresents a robust system to determine MWDs within significantly shorter measurement times and without loss of separation efficiency APC-hyphenation to ynapt G2 offers fractional sample injection into the M-ystem temporal resolution of M spectra significant improve of signal/noise ratio significantly better resolution for the drift time dimension in IM APC-hyphenation helps to ionize structurally different macromolecules in a mixture APC-hyphenation complements EI-IM-M separation, thus giving the opportunity to have more detailed insight into complex polymer samples 19