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Supramolecular polymers

Introduction to polymer science. Supramolecular polymers. 超分子聚合物. 四川大学化学学院. Basic of the Supramolecular. Supramolecular polymer. O. O. O. O. HO. P. OH. P. P. O. OH. O. O. P. O. HO. O. O. O. O.

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Supramolecular polymers

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  1. Introduction to polymer science Supramolecular polymers 超分子聚合物 四川大学化学学院

  2. Basic of the Supramolecular

  3. Supramolecular polymer O O O O HO P OH P P O OH O O P O HO O O O O • A supramolecular polymer is a polymer whose monomer repeat units are held together by noncovalent bonds. • Non-covalent forces that hold supramolecular polymers together include coordination, π-π interactions, and hydrogen bonding. 胸腺嘧啶 H H 腺嘌呤 O O CH2 O O H2C H2C N CH2 O N N H 胞嘧啶 O N H H N N N N 鸟嘌呤 N N N N H O N H H CH3 N O N

  4. Supramolecular polymer Colloid Early 20th century Supramolecular polymer from 1997 Linear polymer from 1930 Jean-Marie Lehn Donald J. Cram Charles J. Pedersen

  5. Definition of Supramolecular polymer • Polymeric arrays of monomeric units that are brought together by reversible and highly directional secondary interactions, resulting in polymeric properties in dilute and concentrated solutions, as well as in the bulk. molecular chemistry atom+ atom → molecular（covalent） supramolecular chemistry molecular+ molecular → supramolecular（noncovalent）

  6. Intermolecular Interactions “Supramolecular Chemistry is the chemistry of the intermolecular bond, concerning the structure and functions of the entities formed by the association of two or more chemical species.” (by Jean-Marie Lehn) Covalent bond • C-O bond 340kJ / mol C-C bond 360kJ / mol • C-H bond 430kJ / mol C=C bond 600kJ / mol • C=O bond 690kJ / mol Driving Force for the Formation of Supramolecular Structures • Hydrophobic interaction < 40 kJ/mol • Electrostatic interaction - 20 kJ/mol • Hydrogen bond interaction 12~30 kJ/mol • Van der Waals interaction 0.4-4 kJ/mol • Cation-π interaction 5-80 kJ/mol • π-π interaction 0-50 kJ/mol • Coordination interaction (Host-guest interaction)

  7. van der Waals Interaction:Sticky Secrets of the Gecko • The toes of the gecko have a special adaptation that allows them to adhere to most surfaces without the use of liquids or surface tension. • the attractive forces that hold geckos to surfaces are van der Waals interactions between the finely divided setae and the surfaces themselves. • Every square millimeter of a gecko's footpad contains about 14,000 hair-like setae. Each seta has a diameter of 5 micrometers.

  8. Hydrophobic interaction • Hydrophobic molecules tend to be non-polar and thus prefer other neutral molecules and non-polar solvents. • Hydrophobic molecules in water often cluster together forming micelles. Water on hydrophobic surfaces will exhibit a high contact angle.

  9. Hydrogen bond • A hydrogen bond is the attractive interaction of a hydrogen atom with an electronegative atom, like nitrogen, oxygen or fluorine. • The hydrogen must be covalently bonded to another electronegative atom to create the bond. • These bonds can occur between molecules (intermolecularly), or within different parts of a single molecule (intramolecularly). • The Hydrogen bonds can vary in strength from very weak (1-2 kJ/mol) to extremely strong (>155 kJ/mol), Typical values include: • F—H... :F (155 kJ/mol or 40 kcal/mol) • O—H... :N (29 kJ/mol or 6.9 kcal/mol) • O—H... :O (21 kJ/mol or 5.0 kcal/mol) • N—H... :N (13 kJ/mol or 3.1 kcal/mol) • N—H... :O (8 kJ/mol or 1.9 kcal/mol)

  10. π-π stacking • π-π stacking are caused by intermolecular overlapping of p-orbitals in π-conjugated systems, so they become stronger as the number of π-electrons increases. • π-π stacking interactions act strongly on flat polycyclic aromatic hydrocarbons such as anthracene, triphenylene, and coronene because of the many delocalized π-electrons. π-πstacking(aromatic interaction). Weak electrostatic interactionbetween aromatic rings. There are two general types: face-to-face and edge-to-face: Face-to-face π-stacking interactions are responsible for the slippery feel of graphite. Similar π-stacking interactions help stabilize DNA double helix. Face-to-face edge-to-face

  11. Self-assembly • Self-assembly is a term used to describe processes in which a disordered system of pre-existing components forms an organized structure or pattern as a consequence of specific, local interactions among the components themselves, without external direction. That is without guidance or management from an outside source (other than to provide a suitable environment). components device molecule components supramolecular

  12. Self-assembly Self-assembly can be classified as either static or dynamic. In static self-assembly, the ordered state forms as a system approaches equilibrium, reducing its free energy. However in dynamic self-assembly, patterns of pre-existing components organized by specific local interactions are not commonly described as "self-assembled" but "self-organized".

  13. Unit of the Supramolecular

  14. Unit of Supramolecular • Based on hydrogen-bonding • Based on π-π stacking • Based on coordination (Host-guest) • Based on miscellaneous interactions

  15. Based on hydrogen-bonding • Liquid Crystalline supramolecular developed by Lehn, based on triple hydrogen bonds

  16. Based on hydrogen-bonding

  17. Based on hydrogen-bonding • Diblock copolymer Tautomerization Homodimerization Heterodimerization UPy-UPy UPy-Napy Ureidopyrimidinones 1,8-naphthyridine

  18. Based on π-π stacking RO OR triphenylenes RO OR R = C5H11, C9H19, C11H23, C6H13 R = C3H7CH(CH3)C3H6CH(CH3)2 RO OR R = (C2H4O)2CH3

  19. Based on π-π stacking a-Hemolysin Heptamer 溶血素 Stacking of Macrocycles via Noncovalent Interaction

  20. Based on coordination Bifunctional metal complexating and its mode of polymerization upon addition of Cu+. N R R N + [Cu(CH3CN)4]+PF6- R R N N Metal Ion N N N PF6- R R Cu N N R PF6- R R Cu N Ar R N R Cu R R PF6- N N N N N

  21. Based on miscellaneous interactions

  22. Characteristics of the Supramoleculars Facile and economic synthesis • Self-assembly involves the aggregation of molecules and macromolecules to thermodynamically stable structures which are held together by weak noncovalent interactions. Reversibility and Self-repairing • Reversible aggregates that can break and recombine on experimental time scales Environmental responsive • The noncovalent interactions are sensitive to environment change, such as solvent, temperature, pH, etc.

  23. Characterization of the Supramolecular

  24. Characterization of the Supramolecular • Detection of surface: AFM, SEM, STM, etc. • Characterization of chemical structure FTIR, 1H-NMR,MS (MALDI-TOF), etc. • Determination of molecular weight GPC • Representation of viscosity Ubbelohde viscometer

  25. AFM tip SPM: Scanning Probe Microscopy Detector and feedback electronics • STM: scanning tunneling microscope • tunneling of electrons between probe and surface • AFM: atomic force microscope • measuring of the force on the probe • MFM: magnetic force microscope • AFM with magnetical probe Photodiode Laser Cantilever & Tip Sample Surface PZT Scanner

  26. Microscopy • Investigating the assembly morphology of the supramolecular • a) POM (polarizing optical microscopy); b) SEM (Scanning electron microscope); • c) TEM (Transmission Electron Microscope); d) AFM

  27. 1H-NMR

  28. MALDI-TOF-MS • Matrix-assisted laser desorption/ionization (MALDI) is a soft ionization technique used in mass spectrometry, allowing the analysis of biomolecules (biopolymers such as proteins, peptides and sugars) and large organic molecules (such as polymers, dendrimers and other macromolecules), which tend to be fragile and fragment when ionized by more conventional ionization methods. • The ionization is triggered by a laser beam (normally a nitrogen laser). A matrix is used to protect the biomolecule from being destroyed by direct laser beam and to facilitate vaporization and ionization. • Time of flight (TOF) describes a methods that measure the time that it takes for an object, particle or acoustic, electromagnetic or other wave to travel a distance through a medium.

  29. MALDI-TOF-MS Spectrum

  30. Application of the Supramolecular

  31. Application of the Supramolecular • Molecular tubes for ion channel 作为离子通道的分子管 • Liquid crystal materials 液晶材料 • Molecular films for separation 用于分离的分子膜 • Micro reaction chamber for catalysis 用于催化的微反应器 • Drug release and delivery 药物缓释和传递

  32. Preparation of copolymer Yang, X. W.; Hua, F. J.; Yamato, K.; Ruckenstein, E.; Gong, B.; Kim, W.; Ryu, C. Y. Angew. Chem., Intl. Ed. 2004, 43, 6471.

  33. Nanotube

  34. Self-healing Contact for 180 min Recovery of initial strength Cut Leibler, L. Nature, 2008, 51, 977–980 Aida, T.Nature, 2008, 451, 895–896

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