Abstract: A method for preparing thin large-area single crystals of diacetylene monomer represented by the formula:R--C.tbd.C--C.tbd.C--R'wherein R and R' are side groups selected such that the diacetylene monomer is polymerizable by a 1,4-addition solid state reaction upon exposure to actinic radiation. The method involves forming a liquid layer containing pure diacetylene monomer between two opposed surfaces; applying pressure to the liquid layer disposed between the two opposed surfaces; and crystallizing the liquid layer disposed between the two opposed surfaces while by evaporation the liquid layer is kept under constant pressure to form a thin large-area single crystal of pure diacetylene monomer.A method for preparing thin large-area single crystals of polydiacetylene is also provided. The method further involves exposing a surface of a thin large-area single crystal of diacetylene monomer to ultraviolet or gamma radiation to form a thin large-area single crystal of polydiacetylene.

Abstract: An optical waveguide made from a unitary organic film has a polydiacetylene core region and a diacetylene monomer cladding substrate region. The index of refraction of the polydiacetylene core region is greater than the index of refraction of the diacetylene monomer cladding substrate region.The method of fabricating the optical waveguide comprises depositing a diacetylene monomer film on a substrate. The diacetylene monomer film is polymerized by ion beam bombardment to a depth less than the thickness of the film. The depth of the polymerization is controlled by the ion mass and energy of the ion beam applied.

Abstract: Methods for preparing thin large-area single crystals of diacetylenes and polydiacetylenes having surface dimensions greater than or equal to about 0.1 mm on all sides and a uniform thickness less than or equal to about 100 microns. The methods involve forming a liquid layer, preferably by melting crystals of a pure diacetylene monomer between two opposed surfaces, one surface being movable with respect to the other; applying pressure to the molten monomer layer disposed between the two surfaces; shearing the molten layer by sliding the movable surface in a single direction that is in a straight line across the molten monomer layer while keeping the molten monomer layer under constant pressure; and crystallizing the shorn molten monomer layer while the shorn molten monomer layer is kept under constant pressure to form a thin large-area single crystal of pure diacetylene monomer.

Abstract: A method for preparing thin large-area single crystals of diacetylene monomer represented by the formula:R--CX.tbd.C--C.tbd.C--R'wherein R and R' are side groups selected such that the diacetylene monomer is polymerizable by a 1,4-addition solid state reaction upon exposure to actinic radiation, is provided. The method involves forming a liquid layer containing pure diacetylene monomer between two opposed surfaces; applying pressure to the liquid layer disposed between the two opposed surfaces; and crystallizing the liquid layer disposed between the two opposed surfaces while the liquid layer is kept under constant pressure to form thin large-area single crystals of pure diacetylene monomer.A method for preparing thin large-area single crystals of polydiacetylene is also provided. The method involves forming a liquid layer containing diacetylene monomer represented by the formula:R--C.tbd.C--C.tbd.

Abstract: Ion implanted polydiacetylenes prepared by implanting ions into substituted polydiacetylenes at fluence levels from about 1.times.10.sup.13 ions/cm.sup.2 to about 1.times.10.sup.17 ions/cm.sup.2 are disclosed. Ion implanted polydiacetylenes exhibit electrical and/or optical properties which are different from those of untreated polydiacetylenes.