Main-chain ferroelectric liquid crystal polymers for electronic nonlinear optics applications [1]

Ferroelectrics

Volumn 309-312, Issue , 2004, Pages 77-82

  Walba, David M ^a   Xiao, Lei ^a   Korblova, Eva ^a   Keller, Patrick ^a   Shoemaker, Richard ^a   Nakata, Michi ^a   Shao, Renfan ^a   Link, Darren R ^a   Coleman, David A ^a   Clark, Noel A ^a  

^a UNIVERSITY OF COLORADO   (United States)

Author keywords

Ferroelectric liquid crystals; Main chain PLC polymers; Nonlinear optics

Indexed keywords

FERROELECTRIC LIQUID CRYSTALS; MAIN CHAIN PLC POLYMERS; POLAR AXIS;

FERROELECTRICITY; GLASS TRANSITION; LIQUID CRYSTALS; OPTICAL FIBERS; POLYMERIZATION; THERMODYNAMICS;

POLYMERS;

EID: 29744436422     PISSN: 00150193     EISSN: 15635112     Source Type: Conference Proceeding    
DOI: 10.1080/00150190490509944     Document Type: Conference Paper

References (13)

1. This is paper # 31 in the series "Design and Synthesis of New Ferroelectric Liquid Crystals." Previous papers in the series: D. M. Walba, E. Körblova, R. Shao, and N. A. Clark, J. Mater. Chem. 11, 2743-2747 (2001). And references therein.
2. a) D. M. Walba, D. J. Dyer, T. Sierra, P. L. Cobben, R. Shao, and N. A. Clark, J. Am. Chem. Soc. 118, 1211-1212 (1996).
3. b) D. M. Walba, D. J. Dyer, P. L. Cobben, T. Sierra, J. A. Rego, C. A. Liberko, R. Shao, and N. A. Clark, "Ferroelectric Liquid Crystals for Nonlinear Optics Applications: Can we Really Do It?" in Thin Films for Integrated Optics Applications, B. W. Wessels, S. R. Marder, and D. M. Walba, Editors, Mat. Res. Soc. Symp. Proc. 392, 157-162 (1995).
4. c) D. M. Walba, D. J. Dyer, X. H. Chen, U. Müller, P. Cobben, R. Shao, and N. A. Clark, Mol. Cryst. Liq. Cryst. 288, 83-91 (1996).
5. D. M. Walba, P. Keller, R. Shao, N. A. Clark, M. Hillmyer, and R. H. Grubbs, J. Am. Chem. Soc. 118, 2740-2741 (1996).
6. a) P. Keller, R. Shao, D. M. Walba, M. Brunet, Liq. Cryst. 18, 915-918 (1995).
7. b) L.-C. Chien, R. G. Petschek, Polym. Mater. Sci. Eng. 72, 350-351 (1995).
8. c) F. Bai, T. Sierra, A. Omenat, J. Barberá, J. L. Serrano Adv. Mater. 8, 752-756 (1996).
9. D.M. Walba, L. Xiao, P. Keller, R. Shao, D. Link, and N. A. Clark, PureAppl. Chem. 51, 2117-2123 (1999).
10. 13C NMR spectra. Mesogen 6 and most intermediates gave satisfactory combustion analyses. The structural assignments are quite secure.
11. 1H NMR was nicely indicative of dimer.
12. In measuring the mesogen length of monomer 6, a fully extended conformation was generated as an MM2 minimum. The mesogen length 1 was taken to be the distance between terminal olefinic hydrogen atoms plus twice the covalent radius of hydrogen; 1 = 37.9 Å. The maximum value of the layer spacing d observed for diene 6 was d = 28.69 Å. The "X-ray tilt" in the smectic C* phase, defined as arccos (d/1) = 40.8°. The "mesogen length" in the polymer was taken as the distance between the mid-points of the terminal double bonds in the fully extended conformation; 1 = 34.6 Å. The observed layer spacing d = 26.98 Å for the polymer gives a calculated tilt of 38.8° for the polymer smectic C* phase. The mesogen length in the dimer was taken as the distance between either of the above mentioned mid-points and the opposite terminal olefinic hydrogen atom plus one covalent hydrogen radius; 1 = 36.2 Å. The observed layer spacing of d = 27.67 Å for the dimer gives a calculated tilt of 40.1Å for the dimer. Due to the low throughput and contrast obtained in SSFLC cells prepared using these materials, reliable optical tilt angles could not be obtained.
13. M. Srinivasarao, R. O. Garay, H. H. Winter, R. S. Stein, Mol. Cryst. Liq. Cryst. Sci. Technol. Sect. A 223, 29-39 (1992).