Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5188397 | Polymer | 2007 | 12 Pages |
The preparation of polyimides containing side-chain chromophores and the long-term aging performance of poled films are described. These materials were compared to guest-host polycarbonate films. Mach-Zehnder optical interferometers were fabricated from these polymers that contained CLD- and FTC-type chromophores. Changes in optical properties were monitored for months at four temperatures ranging from ambient to 110 °C. The isothermal relaxation data were modeled using both a stretched exponential equation and a power law in time equation. The temperature dependency of the time constants of these equations was modeled using a new activation-energy equation: ln(Ï/Ïp) = ER(1 + tanh[(Tc â T)/D])/2RT + Ep/RT where Tc is the central temperature of the transition zone, D is the breadth of the zone, and Es are the activation energies of rigid and pliable materials. Multi-year high-temperature stability of the poled guest-host and side-chain materials was predicted.