1. Lecture 8 Hybrid POSS Class 1E Interpenetrating Networks

2. Ancient Humans also made Hybrid organic-inorganic materials: Maya Blue L. A. Polette, N. Ugarte, M. José Yacamán and R. Chianelli, Sci. Am. Discovering Archaeology, 2000, July–August, 46 Indigo + white clay palygorskite (Mg,Al) 2 Si 4 O 10 (OH)·4(H 2 O)Al Si OH 2 O (also called Fullers Earth)

3. Making Hybrid Materials: Class 1E (Interpenetrating network or IPN) Two lightly crosslinked networks Cannot be untangled. Each network has different mechanical Properties. Together they are stronger, tougher than sum of the individual polymers = synergistic All organic IPN adhesives & coatings

4. Simultaneous Interpenetrating networks The two networks assembled at the same time Phase separation of hard colloidal particles would ruin IPN

5. Sequential Interpenetrating networks The two networks are not assembled at the same time In this case the inorganic network is assembled before the organic

6. If phase separation of particles occurs, it is not an IPN This is a hybrid, inorganic filled polymer, an extreme case of Class 1C. However, many publications refer to similar hybrids as IPN’s

7. Synthesis of poly(methylphenylsiloxane)/phenylene- silica hybrid material with interpenetrating networks and its performance as thermal resistant coating Gao, D. and Jia, M. J. Appl. Polym. Sci. 2012. doi: 10.1002/app.38372

8. Synthesis of poly(methylphenylsiloxane)/phenylene- silica hybrid material with interpenetrating networks and its performance as thermal resistant coating Tensile 10-20 MPa Stable > 300 °C Gao, D. and Jia, M. J. Appl. Polym. Sci. 2012. doi: 10.1002/app.38372

9. Organic–inorganic polymer hybrids based on unsaturated polyester Journal of Non-Crystalline Solids, 2002, 311, 195–198 Sol-gel polymerization of phenyltriethoxysilane in presence of Linear organic polymer Photochemical cure of organic network

10. What about a forming a particle based gel in a monomer as solvent, then polymerize it

11. Macromolecules, 1991, 24 (19), pp 5481–5483 Simultaneous Interpenetrating networks: "Inverse" organic-inorganic composite materials. Monomer containing both silica and organic components splits apart

12. Macromolecules, 1991, 24 (19), pp 5481–5483 Simultaneous Interpenetrating networks: "Inverse" organic-inorganic composite materials. For a hybrid to be an IPN, there must be a non- linear, synergistic effect on the mechanical properties

13. Now onto covalent bonded class 2 hybrids