George and Josephine Butler Polymer Research Laboratory Department of Chemistry University of Florida

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2 The Synthesis of Precision Polyolefins Containing a Variety of Pendant Acid Groups The Wagener Research Group The George & Josephine Butler Polymer Research Laboratory Department of Chemistry University of Florida, Gainesville, Florida USA Century Tower at University of Florida

3 The Scientific Road To Morphology Morphological Structure (ultimately determines performance) Tertiary Structure (how multiple polymer chains organize) Secondary Structure (how a single chain organizes) Primary Structure (repeat unit structure) Understanding Metathesis Reaction Mechanisms

4 The ADMET Reaction - - Polycondensation Chemistry Animation of ADMET Mechanism

5 ADMET Polymerization is Quite Broad In Scope

6 Polyethylene By Step Polymerization Chain Polymerization (polyethylene, polypropylene, PVC, teflon, etc) vs Step Polymerization (polyester, nylon, polycarbonate, etc)

7 Step Polymerization Advantages Step polymerization..no reactivity ratio issues as found in olefin chain copolymerization. Step polymerization..no chain transfer issues as found in olefin chain polymerization.

8 Precision Polyolefins We can control precisely the Branch Identity

9 Precision Polyolefins We can control precisely the Branch Frequency in polyolefins Now with precision placement up to every 75 th carbon

10 ADMET is Metathesis Step Polycondensation Chemistry Symmetrical Diene Symmetrical Repeat Unit When R=H, it s perfectly linear HIGH DENSITY polyethylene Tm = 134 C - ADMET Polyethylene

11 Precision Branches In Polyolefins Example: Methyl Branches

12 Are precisely placed methyl groups included in the crystal lattice? The answer: Yes, they are.

13 Methyl groups are included in the crystal lattice. Orthorhombic Triclinic Triclinic Crystal with Hexagonal Sublattice

14 Precision Branches In Polyolefins What About Alkyl Branches?

15 Some alkyls are included in the crystal lattice. Orthorhombic Triclinic Triclinic Crystal with Hexagonal Sublattice

16 Precision Alkyl Branch Every 21 st Carbon Triclinic ADMET Polyethylenes Alkyl branch on every 21 st carbon T m (ºC) (peak) h m (J/g) Linear ADMET Polyethylene 1 No branch Switches back to orthorhombic Branch in unit cell Branch excluded from unit cell Methyl Gem-dimethyl Ethyl Propyl Butyl Pentyl Hexyl iso-propyl t-butyl sec-butyl Adamantyl R x Journal of the American Chemical Society, 131, (2009)

17 ADMET Polyethylenes Alkyl branch on every 39 th carbon T m (ºC) (peak) h m (J/g) Linear ADMET Polyethylene 1 No branch Branch in unit cell Methyl Ethyl Propyl iso-propyl Butyl Bora Inci Now Postdoc At Illinois Branch excluded from unit cell iso-butyl Pentyl Hexyl Heptyl Octyl Nonyl Decyl Pentadecyl ) Made by ADMET of 1,9-decadiene 29

18 Bora Inci Now Postdoc At Illinois Bora Inci & Wagener, JACS, 31, (2011) 74 Methylene Units 30

19 WAXS Characterization of Precision Polymers Measured at MPIP Presence of (110) and (200) planes confirms the existence of orthorhombic packing! 31

20 Morphology Of Large Defect Branches Is Different WHAT WE THINK: Chains fold to form lamellae devoid of large defects: larger alkyl groups are excluded from the crystal lattice Melting point is determined by branch to branch distance up to 75 carbons. Macromol. Symp., 282, (2009). The distance between branch points has to be large enough to allow crystallization to occur. Folding produces crystals with melting temperatures similar to n-paraffins of similar size.

21 Metathesis & Symmetry Partners No Branches (R=H) Small Precision Branches LARGE Precision Branches Orthorhombic crystals Adapted from: G. Strobl, The Physics of Polymers, Triclinic Crystals Branch included in crystal Branch EXCLUDED Reverts to Orthorhombic

22 Precision Large Branch Morphology Observations First Made at Sumitomo Chemical Company Nozue, Kawashima, et al, Macromolecules, 44, 4030 (2011) Question: Is there some special ordering of the large branches in the amorphous region?

23 Precision Acid Polymer Morphology Kate Opper

24 Precision Acid/Ionomer Functional Groups Grad Student Kate Opper, Now at DuPont Corporate Research

25 ADMET of Protected Acid Easy To Do! PCy 3 O O O Cl Cl Ru PCy 3 O O O x x high vacuum CH 3 x x CH 3 n M w = 75,000 PDI ~ 2.0

26 Hydrogenation Does Two Jobs It Removes The Double Bond Add H 2 O O CH 3 x x = 3, 6, 9 x And The Esteracetal O H 2 (600 psi), Wilkinson's cat. CH 3 toluene, butanol, 75 o C n + O OH CH 3 x+1 x+1 M w = 75,000 n O CH3 PDI ~ 2.0 Travis Baughman, Florida PhD On to postdoc with Bert Meijer, now at DSM

27 COOH COOH COOH COOH Question: Are precisely placed carboxylic acid groups included in the crystal lattice? The answer: No. They are excluded.

28 DSC ADMET Every 21 st, 15 th, 9th Acid group excluded from unit cell for 21st No unit cell No unit cell

29 X-ray Scattering The 21 Polymer COOH COOH COOH COOH Precision ADMET Precise Commercial Random Prof. Karen Winey Chris Chan Now at DuPont Michelle Seitz Now at DSM Francisco Buitrago Grad Student at Penn

30 Morphology.X-Ray Baughman, Chan, Winey, Wagener, Macromolecules, 40, 6564 (2007)

31 Precision Acid-Acid Correlations Persist ABOVE THE MELT! C PEpAA 9.5 Acid groups dimerize (evidence from FTIR) Log Intensity [a.u.] Zn0 PEpAA 13 Zn0 PEpAA 22 Zn0 precise Scattering peak arises from correlations between acid dimers in amorphous matrix Peak shifts to higher q with decreasing acid spacing q [nm -1 ] PErAA 13 Zn0 random Random copolymer has uncorrelated dimer positions no peak Baughman, et al., Macromolecules, 2007,40, 6564 George and Josephine Butler Butler Polymer Polymer Research Research Laboratory Laboratory Department Department of Chemistry of University Chemistry of Florida University of Florida 45

32 Precision Acid Polymers exist in a layered morphology Baughman, Chan, Winey, Wagener "Synthesis and Morphology of Well-Defined Poly(ethylene-co-acrylic acid) Copolymers" Macromolecules, 40, (2007)

33 Precision also leads to a cubic lattice of the ionic aggregates Collaboration With the Winey Group At U. Penn. Seitz, Chan, Opper, Baughman, Wagener, Winey Journal of the American Chemical Society, 132, (2010).

34 Precision Acid Polymer Morphology Kate Opper Prof. Dr. Klaus Mullen MPI-Polymers Dr. Markus Klapper MPI-Polymers Dilyana Markova Postdoc MPI-Polymers

35 Precision Phosphonic Acids PO 3 Et 2 n 1) TMSBr, CH 2 Cl 2 24 hrs, r.t. 2) MeOH 24 hrs, r.t. PO 3 H 2 n Macromolecules, 43, 3690 (2010).

36 Phosphorus, Carbon, Proton Solid State NMR Opper, Fassbender, Brunklaus, Spiess, Wagener Macromolecules, 42, (2009) PO 3 H 2 n M n 18,000 g/mol Aliphatic and methine Hs Aliphatic Cs Phosphonic acid P Hydrogen bonded acid No ethyl methylene No anhydride H Solid state Proton nmr Data 13 C Solid state carbon nmr data 31 P Solid state Phosphorus data

37 Small Angle Carboxylic Acid Polymer COOH COOH COOH COOH Data Generated By Rick Beyer

38 Small Angle Phosphonic Acid Polymer Data Generated By Rick Beyer

39 Precision Acid Polymer Morphology Kate Opper

40 Reverse Solubilization Deprotection Towards Precision Sulfonic Acid Polymers Taylor Gaines

41 Sulfonic Acids Nafion Random Morphology not well understood Developments in Ionic Polymers, A. D. Wilson, A. D., Prosser, H. J., Eds.; Elsevier: London, 1986; Vol. 2; p

42 Precision Layered Morphology Acid Channel Polyethylene Lamellae Seitz, M.; Chan, C.; Opper, K.; Baughman, T.; Wagener, K.; Winey, K. J. Am. Chem. Soc. 2010, 132,

43 Precision Sulfonic Acid Containing Polymers Sought for ~10 years by us with no success until now Opper, K.; Fassbender, B.; Brunklaus, G.; Spiess, H.; Wagener, K. Macromolecules 2009, 42,

44 Precision Sulfonic Ester Protected Polymers No Problem when x = Polymer Science: A Comprehensive Reference; Matyjaszewski, K., Möller, M., Eds.; Elsevier BV: Amsterdam, 2012; Vol. 5; p

45 Deprotection Of Ester In Solution Doesn t Work; BIG Problem! Acid Acid Ester Ester Acid Ester Ester Ester Acid

46 After All These Years Simple Solution Reverse Solubilization Deprotection Insoluble Reactant Heterogeneous Mixture Completely Soluble and Completely Deprotected Insoluble Suspension of Protected Polymers DMSO Molecules Heterogeneous Mixture Homogeneous Solution

47 Precision Sulfonic Acid Polymers A Reality Synthesize geminal precision sulfonic acids as well Characterize morphology of both polymer types, then Membrane Fabrication Proton Conductivity Fuel Cell Membranes Compared With Nafion Geminal polymer doubles acid content

48 We Can Control Morphology In Precision Polyolefins Morphological Structure (what ultimately determines performance) Tertiary Structure (how multiple polymer chains organize) Secondary Structure (how a single chain organizes) Primary Structure (repeat unit structure) Understanding Reaction Mechanisms

49 The Wagener Holiday Party

50 Acknowledgements National Science Foundation Army Research Office University of Pennsylvania (The Winey Research Group) Max Planck Institute For Polymer Research (Wegner, Speiss, Mullen) Sumitomo Chemical, Sandia Laboratories Caltech (Grubbs) & Materia, Inc. (Giardello) for catalyst support University of Florida - Department Of Chemistry