Curable composition, method of preparing cured article, and cured article formed thereby

1. A curable composition, comprising:

a cationic polymerizable material comprising an organopolysiloxane resin represented by the following siloxane unit formula:

(R 1 R 2 R 3 SiO 1/2 ) a (R 4 R 5 SiO 2/2 ) b (R 6 SiO 3/2 ) c (SiO 4/2 ) d

where R 1 -R 6 are independently selected from a substituted or unsubstituted hydrocarbyl group or cationic polymerizable group;

a+b+c+d=1; wherein 0≤a<0.4; 0<b<1; 0<c<1; 0≤d<0.4; and 0.01≤b/c≤0.3; and

a, b, c and d designate an average mole number of each siloxane unit in one mole of the organopolysiloxane resin; and

a diluent component comprising a silane compound having a single, and no more than a single, silicon-bonded cationic polymerizable group, wherein said silane compound is free from any silicon-bonded hydrolysable groups, in an amount sufficient to provide at least 15 percent by weight of the silane compound based on the total weight of the curable composition wherein said silane compound is free of siloxane bonds and has the following general formula:

where R is an independently selected substituted or unsubstituted hydrocarbyl group, Y is said single silicon-bonded cationic polymerizable group, and X is selected from R and SiR 3 .

2. The curable composition of claim 1 wherein said cationic polymerizable group of the organopolysiloxane resin and/or the silane compound is selected from a cyclic ether group, a cyclic ester group, a thietane group, a dioxepane group, acyclic carbonate group, a vinyl ether group, a divinyl ether group, a vinyl ester group, a diene group, a tertiary vinyl group, a styrene group, and a styrene derivative group.

3. The curable composition of claim 1 wherein said silane compound has a viscosity of less than 1,000 cP at 25° C.

4. The curable composition of claim 1 wherein said diluent component further comprises a cationic polymerizable compound other than said silane compound.

5. The curable composition of claim 1 further comprising a catalyst.

6. A method of preparing a cured article, said method comprising:

applying the curable composition of claim 1 on a substrate to form a film; and

curing the film on the substrate to form the cured article.

7. The method of claim 6 wherein the substrate comprises a flexible polymeric substrate.

8. The method of claim 6 wherein curing the film comprises exposing the film to radiation at a dosage sufficient to cure the film.

9. The method of claim 6 wherein curing the film comprises exposing at least one portion of the film to radiation at a dosage sufficient to cure the at least one portion of the film.

10. A cured article formed in accordance with the method of claim 6 .

11. A waveguide comprising a cured article formed in accordance with the method of claim 6 .