Responsive Soft Matter: Structured Fluids and Polymers

The ability of organic matter to undergo reversible structural and electronic reorganization in response to environmental stimuli is directly responsible for the broad utility of soft materials in natural and synthetic systems. In particular, assemblies of molecules or macromolecules engineered to exhibit hard/soft or liquid crystalline phases exhibit a wide range of tunable responses to external electric, magnetic and mechanical fields. Recently, the metal-dependent structural reorganization of a series of mesogenic metalloporphyrazines in the presence of applied magnetic fields has been predicted and characterized. A method to magnetically process these liquid crystals to obtain long-range uniaxial orientation of the columnar superstructures has been demonstrated. The alignment of these materials using mechanical fields will also be described, and contrasted with that of several macromolecular systems, including a new functionalized polyiptycene and two complementary new series of thermoplastic polyurethanes.

“Magnetic alignment of discotic liquid crystals on substrates.”

Lee, J. H.; Kim, H. S.; Pate, B. D.; Choi, S. M.

Physica B 385-6 (2006) 798-800.

“Magnetic uniaxial alignment of the columnar superstructure of discotic metallomesogens over the centimeter length scale.”

Lee, J. H.; Choi, S. M.; Pate, B. D.; Chisholm, M. H.; Han, Y. S.

Journal of Materials Chemistry 16 (2006) 2785-91.

“Effect of the degree of soft and hard segment ordering on the morphology and mechanical behavior of semicrystalline segmented polyurethanes.”

Korley, L. T. J.; Pate, B. D.; Thomas, E. L.; Hammond, P. T.

Polymer 47 (2006) 3073-82.

“Perpendicular organization of macromolecules: synthesis and alignment studies of a soluble poly(iptycene).”

Thomas, S. W. III; Long, T. W.; Pate, B. D.; Kline, S. R.; Thomas, E. L.; Swager, T. M.

Journal of the American Chemical Society 127 (2005) 17976-7.

“Processing the right actuator: The relationship between nanostructure and materials properties of higher-order pyrroles.”

Pate, B. D.; Pytel, R. Z.; Thomas, E. L.

Abstracts of Papers, 229th ACS National Meeting, San Diego, CA (2005) ORGN-238.

“Preparation and physical properties of molecular materials based on metalloporphyrazines (M = Co, Ni, Cu, Zn) and paddlewheel complexes (M = Mo, W, Ru).”

Pate, B. D.

Doctoral Thesis (2004).

“Structure and magnetic alignment of metalloporphyrazine columnar aggregates in their mesophases and crystalline phases.”

Pate, B. D.; Choi, S. M.; Werner-Zwanziger, U.; Baxter, D. V.; Zaleski, J. M.; Chisholm, M. H.

Chemistry of Materials 14 (2002) 1930-36.

“Magnetic alignment of metalloporphyrazine columnar aggregates.”

Pate, B. D.; Baxter, D. V.; Chisholm, M. H.; Werner-Zwanziger, U.; Zaleski, J. M.

Abstracts of Papers, 220th ACS National Meeting, Washington, DC (2000) INOR-491.

“Preparation of lanthanide bisporphyrin derivatives.”

Pate, B. D.; with Chisholm, M. H.; Zaleski, J. M.

(authors alphabetized)

Book of Abstracts, 217th ACS National Meeting, Anaheim, Calif. (1999) INOR-076.

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