Hybrid POSS Lecture 12 Class 2B: Inorganic and organic polymeric phases are mixed and form covalent interactions

tin oxides and polymers with carboxylate groups. But not a lot in the literature

Cross-linking through fullerenes Used to purify C 60. Did not look at mechanical properties Requires solvent to prepare

Cross-linking through fullerenes: my new idea Liquid polymer- no solvent needed

Modified organic polymers: Trialkoxysilyl side groups

Polybutadiene with side groups

Grafted triethoxysilyl groups on polyethylene for moisture crosslinking May also be applied with vinyltriethoxysilane and RF plasma Excellent for moisture curing polyethylene

Macromolecules, 2004, 37 (10), pp 3532–3535 Anisotropic Micellar Nanoobjects from Reactive Liquid Crystalline Rod−Coil Diblock Copolymers

Modified organic polymers: Trialkoxysilyl end groups

Macromolecules 1992,25, Hydrogenated polybutadiene telechelics with triethoxysilyl groups

Triethoxysilyl terminated polysulfone Macromolecules 1991;24:3449–50. Anneal > 200 °CTiO 2 sol in THF Tailorable refractive index 1.6 < n < 1.8

Drug delivery hybrid gel Polyethylene glycol Treithoxysilyl group on each end Urea linkage

Drug delivery hybrid gel

PEO Bridged polysilsesquioxane hybrids Bacteriocide Ag-silsesquioxane coatings Biomacromolecules, 2007, 8 (4), pp 1246–1254 Polymer electrolytes Solid State Ionics, 1999, 116, 197– 209 Coatings for steel. Adv. Technology 2008, 27, Electrochemically deposited coatings for stints New J. Chem., 2009, 33, Luminescent materials J. Non-Crystal Solids 2006, 352, 2292–2295 & Chem. Mater., 2004, 16 (13), pp 2530–2543 Contolled druge release Chem. Mater., 2009, 21 (3), pp 463–467

PEO bridged polysilsesquioxanes for polymer electrolytes New J. Chem., 2012, 36,

Templating of structures and pores in hybrids, inorganics and organics In templating, you build a material around some molecule, macromolecules or liquid crystal Opals were used as templates for inverse opals and photonic solids (described in an earlier lecture). First we will see polymers phase segregation during sol-gel polymerization generating bone linke structures in hybrids. Then we will look at liquid crystalline surfactant or block copolymer templates

Polymer phase separation templation of macropores

Using other phase separations to control how particles aggregate Surfactants Polymers Block copolymers Hydrophilic Phase Hydrophobic Phase Monomers are often dissolve in this phase Hydrolyzed monomers and polymers are often dissolve in this phase Polymers are not very soluble in each other and will phase separate like oil and water Larger structures Smaller structures

Cited over 10,200 times

The Mobil patent was duplicating something already in the literature Somebody did not do a careful literature search!!!!!!

Traditional ionic surfactants used in mesoporous materials templation

Traditional non-ionic surfactants used in mesoporous materials templation

Phase separation: surfactants

Pore models of mesostructures with symmetries of (A) p6mm, (B) Ia3 ̄ d, (C) Pm3 ̄ n, (D) Im3 ̄ m, (E) Fd3 ̄ m, and (F) Fm3 ̄ m. MCM-41 FDU-12SBA-16 SBA-1 FDU-2 MCM-48

Adv. Mater 1999, Brinker

First model for surfactant templating: assumes liquid crystal occupies entire solution A few nanometers in diameter

Published in: Avelino Corma; Chem. Rev. 1997, 97,

1) n-Hexadecyltrimethylammonium bromide (2.5 g, mol) was dissolved in deionized water (50 g) 2) To this surfactant solution, 13.2 g of aqueous ammonia (32 wt.%, 0.25 mol) and 60.0 g of absolute ethanol (EtOH, 1.3 mol) were added and the solution was stirred for 15 min (250 rpm). 3) TEOS (4.7 g, mol, freshly distilled) was added at one time resulting in a gel. 4) After stirring for 2 h the white precipitate was filtered and washed with 100 ml of deionized water and 100 ml of methanol. 5) After drying overnight at 363 K, the sample was heated to 823 K (rate:1 K min−1) in air and kept at that temperature for 5 h. Synthesis of MCM-41 spheres Microporous and Mesoporous Materials, 1999, 27, 207–216

Synthesis of MCM-41 silica spheres Microporous and Mesoporous Materials, 1999, 27, 207–216 X-ray diffraction pattern of an MCM-41 sample prepared in heterogeneous medium with n-hexadecylpyridinium chloride as template.

Size of MCM 41 pores can be controlled by process conditions

TEM image of the honeycomb structure of MCM-41 and a schematic representation of the hexagonal shaped one-dimensional pores. A close look at the structure shows that it is made of small amorphous silica particles Just like the silica in living sponges > 1 nm in size

X-Ray Diffraction (XRD) These materials show peaks at very small angles = larger structures than are typical in crystalline materials

formation mechanism of the templated nanoporous silicas New mechanism has individual surfactant molecules and micelles playing a role in developing architecture

.Chem. Rev., 2002, 102 (11), pp 4093–4138 Zeolite: silicalite

Structure of SBA-1 or SBA-6 observed as an electron density and described either in terms of a clathrate structure or as a surface enveloping the micellar templating agents Nature, 2000, 408, 449 Electron micrographs of SBA-1 and SBA-6 along [100] What are some of these materials and what do they look like (SBA-Santa Barbara.

Plane-projection of CDF (a), respective TEM image fragment (b) and its simulation (c).

Electronic density maps and bicontinuous cubic structure of MCM-48 Chem. Mater., 1996, 8, 1141

HREM images of CMK-4 along the three zone axes [100], [110] and [111] together with a representation of the carbonaceous surface. J. Phys. Chem. B, 2002, 106, 1256

Chem. Rev., 2011, 111 (2), pp 765–789 How organic templates can control porosity of materials

Liquid crystal forms then monomer enters and reacts Monomer starts reacting and interacting with surfactant as the liquid crystal forms

Making Hybrid Materials: Class 2C (Templating) Shown here with block copolymer

Tools for hierarchical materials structures Phil. Trans. R. Soc. A 28 April 2009 vol. 367 no

Other challenges Ladder polysilsesquioxanes = super strong materials Pure polyhedral analogs the size of C 60 Fundamentals of particle formation and connectivity at nm length scale Mechanochemical direction of materials-like exercising developing muscles

Good-bye Thank you Good Luck I will be here until November 23 & should be back this summer