Physics and Chemistry of Hybrid Organic-Inorganic Materials Professor Douglas A. Loy Visiting from the University of Arizona, United States

Syllabus Mondays 10-10:50, 10:55-11:45 AM Wednesdays 10-10:50, 10:55-11:45 AM Fridays 1:45-2:35 PM, 2:40-3:30-PM Last day of class is June 14 th 4 quizes No final exam Attendance and participation are graded\

Course website For lecture slides and other info. Not at HIT website, at Loy research website: Go to loy research group home page and select “courses” on menu at top. Class website: “Chemistry and Physics of Materials Harbin Institute of Technology ” is the second entry. Direct url: institute-technology---hybrid-materials- course.html

Lectures Lecture 1: Introduction to hybrids May 27 Lecture 2:Structures of HybridsMay 27 Lecture 3: Properties of HybridsMay 29 Lecture 4:Physics of phase separation & solutionsMay 29 Quiz 1May 31 Lecture 5:Naturally occurring hybridsMay 31 Lecture 6: Making hybrids by physical mixing of materialsJune 3 Lecture 7:Polymerizing monomers to make hybridsJune 3 Quiz 2June 5 Lecture 8: PolysilsesquioxanesJune 5 Lecture 9: POSS systems June 7 Lecture 10: Bridged polysilsesquioxanesJune 7 Quiz 3June 10 Lecture 11: Polymerizing organic monomers in inorganics materialsJune 10 Lecture 12: Polymerizing inorganic monomers in organic polymersJune 12 Lecture 13: Surfactant templating materialsJune 12 Lecture 14 Frontiers in hybridsJune 14 Quiz 4June 14

What are hybrid organic-inorganic materials? Mixtures of organic materials and inorganic materials Very important materials for 21 st century economy

Lecture Objectives Identify hybrid organic inorganic materials List benefits of using hybrids Basic ways hybrids are put together Understand what is meant by organic, inorganic, monomer, polymer and material. Understand the size (length scales) in hybrids know applications for hybrid materials List hybrid organic-inorganics found in nature

Identifying hybrids:Both organic and inorganic materials combined Steel, silica, & carbon – inorganic (strong) Poly(isoprene) rubber – organic (flexible, adhesive, elastic) Centimeter Length scales

Identifying hybrids: often have two phases A close up look at the rubber in the tire shows about 30 wt% silica particles The inorganic silica particles are nm in size. The organic (polyisoprene rubber) is continuous

Identifying hybrid organic materials with Scanning electron microscopy Inorganic particle Organic polymer Features are often too small to see with the eye

Identifying Hybrid organic- inorganic materials Hybrids may be a composite of multiple phases or a single hybrid phase. multiphase composite – examine by SEM, AFM, TEM Single phase material – elemental analysis Quick method: burn the material and see if there is a residue. Organic burns, most inorganic will leave a residue

Benefits of Hybrid Organic Inorganic Materials Stronger and stiffer than organics Tougher and more flexible than inorganics Less flammable than organics When melted, more viscous (non- dripping) Tailored optical properties (refractive index, transparency, scattering, absorptions) High surface area porous materials

How are hybrids put together? Physically mixing inorganic materials and organic polymers Polymerizing an organic monomer in an inorganic material Polymerizing an inorganic monomer in an organic material or polymer Polymerizing a monomer with both organic and inorganic parts

Organic monomers react by polymerizing into macromolecules As many as 20,000 monomers may be linked together to make a single macromolecule Equivalent to this shorthand structure

Polymerization of inorganic or hybrid monomers to form materials Hydrolysis: Condensation: Net Polymerization: Shown here for formation of a silsesquioxane

Hybrid from organic polymer and inorganic monomer Solid Organic Polymer Cool melt below Tg or evaporate solvent inorganic particles dispersed in solution or melted polymer solution or molten organic polymer dissolve or melt Pre-made inorganic particles

A hybrid might have silica nanoparticles mixed in with the polystyrene Such hybrids have higher glass transition temperatures, and are stronger, more flame resistant

Hybrid from organic polymer and inorganic monomer Inorganic particle Organic polymer

Hybrid from organic polymer and inorganic monomer Solid Organic Polymer Inorganic Monomer (liquid) & catalyst Mixture of Organic polymer and Inorganic Monomer & catalyst Monomer polymerizes & forms particles Solution or emulsion melt or dissolve

Preparation by adding organic monomer into pores in inorganic material then polymerizing organic Monomer (liquid) & catalyst Monomer must be soluble in polymer Porous Inorganic Material Mixture of Organic Monomer & Inorganic Material Monomer polymerizes & fills pores with particles

Polymerize monomer that has both organic and inorganic parts connected together with bonds Hybrid Monomer in solution Sol-gel polymerization Hybrid organic- inorganic particles dispersed in solvent Hybrid CoatingHybrid Gel Hybrid Particles

Structure of Hybrids atomic (Angstrom) macromolecular (nm’s) Colloidal or nanostructure (< 100 nm) Microstructure or morphology (> 100 nm) 1 micron

Length Scales

Applications of hybrid materials Tethers for Bio-molecules Coupling agents For composites Toughened Composites Protective coatings Chromatographic Materials (X-Bridge ®, Waters) Photoresists for Lithography Photographs courtesy of Gelest, Inc. and Waters Co.

Applications of hybrids Strong, low density structural materials Impermeable hybrids to prevent loss of pressure Protective coatings on solar panels

More applications of hybrid materials Adhesives Metal Scavenger “resins” Sensor coatings Low  Dielectrics Optical coatings encapsulants Plus ceramic precursors (e.g. SiC)

Hybrid Organic-Inorganic materials are common in nature Nacre Argonite (CaCO 3 ) plates as inorganic with protein (polyamide) as organic Animals Plants phytolith Bone, teeth, spines in echinderms Mussel shells, sponges, diatoms and corals are composed of hybrid organic- inorganic materials Organic phase is biopolymer Carbohydrates are the template and organic phase

Summary: Hybrid materials are combinations of organic and inorganic components the organic and inorganic parts can be in one phase or in separate phases. Single phase hybrids are often made from hybrid monomers Hybrids can have improved mechanical properties, thermal & chemical stability, and modified optical properties. Hybrids have many applications