Anionic polymerizations of seven styrenes para-substituted with N-arylimino groups were carried out in THF at −78 °C with oligo(α-methylstyryl)dipotassium and -dilithium as the initiators. The N-aryl functionalities contained phenyl (1), 2-(tert-butyl)phenyl (2), 2,6-dimethylphenyl (3), 2,6-diethylphenyl (4), 2,6-diisopropylphenyl (5), 4-cyanophenyl (6), and 2,3,4,5,6-pentafluorophenyl (7) groups. The monomers 3−5 underwent anionic polymerization quantitatively to produce the polymers having predicted molecular weights based on molar ratios of monomers to initiators and narrow molecular weight distributions, the M w/M n values being around 1.1. On the other hand, no polymeric products were obtained from the polymerization mixture of 1, 2, 6, and 7 under identical conditions. The bulkiness of the two ortho alkyl substituents on the N-aryl moiety was necessary to achieve the anionic living polymerization of styrenes bearing N-arylimino groups. Well-defined new block copolymers having poly(5) segments were synthesized by the sequential addition of 5 and styrene or tert-butyl methacrylate. The resulting poly(3−5) could be quantitatively transformed into the poly(4-formylstyrene) having tailored chain structures by the acid hydrolysis of N-arylimino moieties.

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Novel photosensitive sol-gel materials, which are comprised of siloxane oligomers and a photo acid generator (PAG), have been developed. The spectroscopic studies led to the observation that sol-gel reaction was affected by a balance of between PAG and amine content added as catalysts. Additionally, the balance strongly influenced the line pattern profile formed with exposure, which indicated that the photolithographic properties changed from negative to positive tone with the amine content. An optical channel waveguide based on sol-gel materials was fabricated through photolithographic processing and showed low propagation losses that were 0.3 dB/cm and 0.6 dB/cm at 1.31 µm and 1.55 µm, respectively, in addition to excellent long-term reliability.

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