Making Negative Poisson's Ratio Microstructures by Soft Lithography

✍ Scribed by B. Xu; F. Arias; S. T. Brittain; X.-M. Zhao; B. Grzybowski; S. Torquato; G. M. Whitesides

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 411 KB
• Volume: 11
• Category: Article
• ISSN: 0935-9648
• DOI: 10.1002/(sici)1521-4095(199910)11:14<1186::aid-adma1186>3.0.co;2-k

✦ Synopsis

quenching to room temperature. As a result, the polarization bandwidth was found to increase by a factor of 2.4 over what was expected of a constant-pitch film. The increased bandwidth was attributed to a pitch gradient resulting from photoinduced racemization of the chiral dopant at the irradiated surface with simultaneous diffusion through the film. This is the first demonstration of a pitch gradient generated in the mesomorphic fluid state and then frozen in a glassy chiral-nematic film.