University of Southern California Sun. Sep. 21, 2014 
 
Home IntroductionObjectivesResearchFaculty and StaffNews and EventsResources

Faculty
Associates / Fellows
Advisory Board
Home


William P. Weber

  
Emeritus Professor of Chemistry

Office: SGM 418
Phone: (213) 740-7036
Fax: (213) 740-2701
Email: wpweber@usc.edu

 

Research Focus

 

Growth of marine organisms such as barnacles and algae on surfaces of ships is an age old problem which results in deterioration of ship performance and increased fuel consumption. For the last several decades this problem has been addressed by the use of coatings which incorporated toxic organo tin compounds. Due to environmental problems caused by release of these materials, their use has been recently prohibited by international treaty.
To maintain marine efficiency, new non-toxic biofoul release coatings are needed. We are actively working on the preparation of such novel environmentally friendly biofoul release, anti-corrosion coatings for marine applications.

This project requires synthesis of novel siloxane polymers. We also work on crosslinking these to yield coatings. Properties of the polymers must be designed to permit crosslinking to yield hydrophobic coatings with desired properties. Among these are low surface energy, low modulus, and low glass transition temperature.

Graduate students synthesize novel ring strained cyclosiloxane monomers. We development methods to polymerize these to yield reactive siloxane polymers and further utilize polymer reactivity to control crosslinking chemistry to prepare films. Preparation of branched polysiloxanes such as star and hyperbranched is actively pursued. Synthesis of copolymers with controlled molecular weight distribution and microstructure is essential.
Complete spectroscopic characterization of novel monomers, polymers and copolymers is essential. 29Si NMR is particularly useful for characterization of polysiloxanes. The thermal properties (glass transition temperature Tg, thermal stability TGA and differential thermo- mechanical DTMA properties of polymers and coatings are determined. Development of new crosslinking chemistry is a major area of study. Photo generated acid catalyzed crosslinking as well as amine/epoxy cures are actively studied. Surface energies of coatings are measure by static, and dynamic contact angle measurements. Active collaborations with several marine biology groups (Professors Callow, U. of Birmingham, England, and D. Wendt, California State U. San Luis Obispo, CA) permit us to test our coatings properties against marine organisms as biofoul release coatings. The corrosion resistance of our films is done in collaboration with Professor F. Mansfeld of the Materials Science Dept. at USC.

We believe that work in this area provides significant breadth of training for graduate students.

Chemical modification of polymers is area of long standing interest. We are interested in utilizing ruthenium catalysis to activate the ortho C-H bond of aromatic ketones for anti-Markovnikov addition across the C-C double bonds of vinyl siloxanes.

References

 
1. Synthesis of a,w-bis Epoxy Oligo(1'H, 1'H, 2'H, 2'H-Perfluoroalkyl Siloxane)s and Properties of their Photo-Acid Crosslinked Films, M.A. Grunlan, N.S. Lee, G. Cai, T. Gadda, J.M. Mabry, F. Mansfeld, E. Kus, D.E. Wendt, G.L. Kowalke, J.A. Finlay, J.A. Callow, M.E. Callow and W.P. Weber, Chemistry of Materials, 16, 2433-2441 (2004).
2. Synthesis of 1,9-bis[Glycidyloxypropyl]penta(1H',1H',2H',2H'-perfluoroalkylmethyl- siloxane)s and Copolymerization with Piperazine, M.A. Grunlan, N.S. Lee and W.P. Weber, Polymer, 45, 2517-2523 (2004).
3. Synthesis and Thermal Crosslinking of Benzophenone Modified Poly(dimethylsiloxane)s, J.M. Mabry and W.P. Weber, J. Polymer Sci: Part A: Polymer Chem., 42, 5514-5522 (2004).
4. Synthesis of Terminal Si-H Irregular Tetra-branched Star Polysiloxanes, Pt-Catalyzed Hydrosilylation with Unsaturated Epoxides. Polysiloxane Films by Photo-acid Catalyzed Crosslinking, G. Cai and W.P. Weber, Polymer, 45, 2941-2948 (2004).
5. Selectivity in Anionic and Cationic Ring-Opening Polymerizations of Tetramethyl-1-(3'- trifluoromethylphenyl)-1-phenylcyclotrisiloxane and Tetramethyl-1-{3',5'-bis(trifluoro- methyl)phenyl-1-phenylcyclotetrasiloxane, T.M. Gadda, A.K. Nelson and W.P. Weber, J. Polym. Sci. Part A, Polym. Chem., 42, 5235-5243 (2004).
6. Synthesis and Characterization of Octakis(3,3,3-trifluoropropyldimethylsiloxy)cyclotetra- siloxane (I), octakis[tridecafluoro-2,2,5,5-tetramethyl-2,5-disilatridecanoxy]cyclotetra- siloxane (II) and octakis(7-pentafluorophenyl-2,2,5,5-tetramethyl-2,5-disilaheptanoxy)- cyclotetrasiloxane (III), C.J. Teng, G. Cai and W.P. Weber, J. Fluorine Chem., 125, 1451-1455 (2004).
7. Crosslinking of 1,9-bis[Glycidyloxypropyl]penta(1H',1H',2H',2H'-perfluoroalkylmethyl- siloxane)s with a,w-Diaminoalkanes: Cure Behavior and Film Properties, M.A. Grunlan, N.S. Lee and W.P. Weber, J. Appl. Polym. Sci., 94(1), 203-210 (2004)
8. Novel Thermal Crosslinking of Siloxanes, J.M. Mabry and W.P. Weber, Polymer Preprints, 45(1), 682-683, 2004.
9. 9. Selectivity in Anionic and Cationic Ring-Opening Polymerization of Tetramethyl-1-(3'- trifluormethylphenyl)-1-phenylcyclotrisiloxane, T.M. Gadda, A.K. Nelson and W.P. Weber, Polymer Preprints, 45(1), 696-697 (2004).
10. Selectivity in Anionic and Cationic Ring-Opening Polymerization of Tetramethyl-1-[3',5'- bis(trifluoromethyl)phenyl-1-phenylcyclotrisiloxane, A.K. Nelson, T.M. Gadda and W.P. Weber, Polymer Preprints, 45(1), 698-699 (2004).
11. Crosslinking of a,w-(Epoxy)fluorosiloxanes with a,w-Diaminoalkanes: Cure Behavior and Properties, M.A. Grunlan, N.S. Lee and W.P. Weber, Polymer Preprints, 45(1), 581-582 (2004).
12. Synthesis of w-Si-H Tetra-branched Star PDMS. Conversion by Photo-Acid Catalyzed Crosslinking to Films, G. Cai and W.P. Weber, Polymer Preprints, 45(1), 710-711 (2004).
13. Synthesis of 1,9-Bis[Glycidyloxypropyl]penta(1H',1H',2H',2H'-Perfluoroalkylmethyl- siloxane)s and
Copolymerization with Piperazine, M.A. Grunlan, N.S. Lee and W.P. Weber, Polymer Preprints, 45(1), 712-713 (2004).
14. New Approaches to Modification of Siloxane Properties by Crosslinking, T.M. Gadda and W.P. Weber, Abstracts of Paper, 227th ACS Natl. Mtg, Anaheim, CA., 2004. Invited presentation..

(c) 2014 Loker Hydrocarbon Institute