Low loss electro-optic polymers and devices made therefrom

An electro-optic chromophore comprising a compound whose formula is represented by the structure

• 14
• wherein
• (a) Z is O or S;
• (b) R1 and R1a each are, independently, H or a C1-C10 alkyl group;
• (c) R2 and R3 each are, independently, H, a substituted or unsubstituted C1-C10 alkyl, a substituted or unsubstituted C2-C10 alkenyl, a substituted or unsubstituted aryl, a substituted or unsubstituted alkylaryl, a substituted or unsubstituted carbocycle, a substituted or unsubstituted heterocycle, or a substituted or unsubstituted cyclohexyl;
• or R2 and R3 together form a ring structure or substituted ring structure;
• (d) q is in the range of 1 to 3;
• and
• (e) D is an electron donor having one or a plurality of terminally pendent, polymerizable cyclic ether or cyclic thioether groups.

A non-linear optical chromophore comprising a compound whose formula is represented by the structure

• 15
• wherein
• (a) A is S or NR5,
• (b) R4 is selected from the group consisting of epoxy, episulfide, oxetane and thietane, and
• (c) R5 is selected from the group consisting of C1-C6 alkyls, epoxy, episulfide, oxetane and thietane.

A photocurable composition suitable for the fabrication of electro-optical elements and devices, said composition comprising:

• (a) a non-linear optical chromophore comprising a compound whose formula is represented by the following Structure II
• 16
• wherein
• (i) D is an electron donating group having one or a plurality of terminally pendent, polymerizable cyclic ether or cyclic thioether groups;
• (ii) Z is O or S,
• (iii) R1 and R1a are H or a C1-C10 alkyl group;
• and
• (iv) R2 and R3 each are, independently, H, a substituted or unsubstituted C1-C10 alkyl, a substituted or unsubstituted C2-C10 alkenyl, a substituted or unsubstituted aryl, a substituted or unsubstituted alkylaryl, a substituted or unsubstituted carbocycle, a substituted or unsubstituted heterocycle, or a substituted or unsubstituted cyclohexyl;
• or R2 and R3 together form a ring structure or substituted ring structure
• (v) q is in the range of 1-3;
• and
• (b) a host polymer or oligomers containing the groups reactive with the chromophore's reactive groups;
• and
• (c) a cationic photoinitiator.

An optical device or element made from a photocured composition comprising:

• (a) a compound whose formula is represented by the structure
• 17
• wherein
• (i) D is an electron donor having one or a plurality of terminally pendent, polymerizable cyclic ether or cyclic thioether groups;
• (ii) B is or contains at least one bivalent aromatic ring;
• and
• (iii) R2 and R3 are each, independently, either H or a substituted or unsubstituted C1-C10 alkyl, a substituted or unsubstituted C2-C10 alkenyl, a substituted or unsubstituted aryl, a substituted or unsubstituted alkylaryl, a substituted or unsubstituted carbocycle, a substituted or unsubstituted heterocycle, or a substituted or unsubstituted cyclohexyl;
• or R2 and R3 together form a ring structure or substituted ring structure
• (b) a copolymer of (i) a maleimide first monomer and (ii) one or a plurality of second monomers.

A method for fabricating an optical or electro-optic structure containing a photodefinable high μβ chromophore layer, said method comprising the steps of:

• (a) applying to a substrate a composition containing a chromophore having at least one terminal cationically polymerizable group to form a photopolymerizable composition layer, said composition including at least one cationic photoinitiator;
• (b) imagewise exposing the photopolymerizable composition layer to sufficient actinic radiation to effect the at least partial polymerization of an imaged portion and to form at least one non-imaged portion of said composition layer;
• (c) removing said at least one non-imaged portion without removing said imaged portion, thereby forming a light transmissive pattern from said imaged portion;
• (d) applying an cladding polymerizable composition onto the patterned layer;
• and
• (e) at least partially curing said cladding composition, wherein said cladding and the core-interfacing surface of said support have a lower refractive index than said core.

A method for fabricating an optical or electro-optic structure containing a photodefinable high μβ chromophore, said method comprising the steps of:

• (a) spin coating a substrate with a first polymeric cladding layer material having an refractive index less than the refractive index of the chromophore containing material that will be subsequently applied;
• (b) exposing the material of Step (a) to actinic radiation for a selected time, followed by baking at a selected temperature for a selected time to form a substrate having a first bottom cladding layer adhered thereto;
• (c) spin coating on the first cladding material a second cladding layer material having an refractive index less than that of the chromophore containing waveguide material that will be subsequently applied, followed by prebaking at a selected temperature for a selected time;
• (d) placing a positive photomask over the second cladding material and applying actinic radiation followed by a baking at a selected temperature for a selected time to produce a form of an optical or electro-optical element or device;
• (e) developing the form of Step (d) by washing away uncured polymer with a solvent in which the second cladding material is soluble;
• (f) spin coating a high μβ chromophore/polymer composition containing a cationic photoinitiator to the form of Step (e) and curing same in an inert atmosphere by application of actinic radiation, followed by baking in an inert atmosphere, at a selected temperature for a selected time to thereby form an optical or electro-optical structure containing a high μβ chromophore;
• (g) spin coating a top overcladding material on the structure of Step (e), and curing same as described in Step (b) to produce said optical or electro-optical element or device
• wherein said chromophore contains terminal reactive moieties selected from the group consisting of cyclic ethers and cyclic thioethers.