title: Development of microporous structure and its application to optical film for cellulose triacetate containing diisodecyl adipate.
abstract: Phase separation in plasticized cellulose triacetate (CTA) films is investigated to produce a microporous film that can be used in optical devices. Hot-stretched CTA films containing diisodecyl adipate (DIDA) show negative orientation birefringence similar to the hot-stretched pure CTA. After extracting DIDA from the stretched films by immersion into an organic solvent, however, the films exhibit positive birefringence. Moreover, the magnitude of the birefringence increases with the wavelength, known as extraordinary dispersion, which is an essential property in the preparation of an ideal quarter-wave plate. Numerous ellipsoidal pores with micro-scale were detected in the film after the immersion, indicating that DIDA were segregated and formed ellipsoidal domains in the CTA matrix during annealing and stretching. These results indicate that extraordinary wavelength dispersion is given by the combinations of orientation birefringence from CTA and form birefringence from micropores. Furthermore, it was found that annealing time and stretching condition affect the phase separation as well as the shape and size of pores.
authors: School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi 923-1292, Ishikawa, Japan.
authors: Hikaru
authors: H
authors: Shimada
authors: School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi 923-1292, Ishikawa, Japan.
authors: Shogo
authors: S
authors: Nobukawa
authors: School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi 923-1292, Ishikawa, Japan. Electronic address: m_yama@jaist.ac.jp.
authors: Masayuki
authors: M
authors: Yamaguchi
mesh_terms: D000272:Adipates / Q000737:chemistry*; D002482:Cellulose / Q000031:analogs & derivatives* / Q000737:chemistry; D008567:Membranes, Artificial; D055095:Optics and Photonics / Q000379:methods*; D012997:Solvents / Q000737:chemistry; D013696:Temperature
chemical_list: D000272:Adipates; D008567:Membranes, Artificial; D012997:Solvents; C029900:adipic acid; D002482:Cellulose; C024671:cellulose triacetate
keywords: Birefringence; Blends; Cellulose triacetate; Microporous structure; Optical film