Single-crystal optical waveguides of 4-dimethylamino-N-methyl-4-stilbazolium tosylate (DAST), an organic material with a large electro-optic coefficient, have been obtained. DAST decomposes at its melting temperature, making its growth from the melt difficult. However, graphoepitaxy allows for >1 mm s−1 growth, 1×105 times faster than conventional techniques, and produces crystals of the correct dimensions for optical waveguides, 1–15 μm on a side and 5–10 mm long. The crystals grow with the c-axis normal to the substrate, and with in-plane orientation determined by lithographic patterning. The electro-optic coefficient dn/dE is 600±300 pm V−1 at 1.55 μm wavelength. Optical losses are <10 dB cm−1.

The synthesis of a novel series of hybrid monomers containing cationically polymerizable cycloaliphatic epoxide and 1-propenyl ether functional groups in the same molecule has been conducted. Detailed structure−reactivity studies of the diaryliodonium salt-induced cationic photopolymerizations of these monomers indicate that the rate of epoxide ring-opening polymerization is markedly enhanced by the presence of the 1-propenyl ether group. At the same time, the polymerization of the 1-propenyl ether groups in such hybrid monomers is retarded. A mechanism involving the free-radical-induced decomposition of the photoinitiator has been proposed which serves to amplify the rate of the photoinitiated cationic epoxide ring-opening polymerization.

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