Polysiloxane composition, molded body obtained from the same, and optodevice member
View Patent ↗The present invention provides a polysiloxane composition maintaining high transparency over a wide wavelength region and a wide temperature region and being excellent in heat resistance, low-dielectric characteristics, workability, and the like. A polysiloxane composition includes (A) a polysiloxane which is composed of a polysiloxane compound having a polyhedral skeleton having 6 to 24 Si atoms in its molecule and which has at least one alkenyl group bonded directly or indirectly to a Si atom constituting the polyhedral skeleton, (B) a polysiloxane having a hydrosilyl group, and (C) a hydrosilylation catalyst.
1. A method for molding a polysiloxane composition, wherein the method comprises:
dissolving components (A) to (C) in a solvent, wherein
the component (A) is a polysiloxane, which is composed of a polysiloxane compound having a polyhedral skeleton having 6 to 24 Si atoms in its molecule and which has at least one alkenyl group bonded directly or indirectly to a Si atom constitution the polyhedral skeleton,
the component (B) is a polysiloxane having a hydrosilyl group, and
the component (C) is a hydrosilylation catalyst;
reacting a part of alkenyl groups of the component (A) and a part of hydrosilyl groups of the component (B);
distilling off the solvent to form a liquid resin composition; and then
curing the polysiloxane composition.
2. A molded body obtained by the method for molding the polysiloxane composition according to claim 1 .
3. The method according to claim 1 , wherein a component (D), which is a curing retarder, is dissolved in the solvent together with the components (A) to (C).
4. The method according to claim 1 , wherein the component (A), the Si atom constituting the polyhedral skeleton is bonded to the alkenyl group through a siloxane bond.
5. The method according to claim 1 , wherein the alkenyl group in the component (A) is a vinyl group.
6. The method according to claim 1 , wherein the component (B) is a polysiloxane having a linear structure.
7. The method according to claim 1 , wherein the component (B) has a hydrosilyl group at a terminus of its molecule.
8. The method according to claim 1 , wherein the degree of polymerization of the component (B) is 2 to 300.
9. The method according to claim 1 , wherein the component (B) is a cyclic siloxane compound having a hydrosilyl group.
10. The method according to claim 1 , wherein the polysiloxane as the component (B) has at least two hydrosilyl groups.
11. The method according to claim 1 , wherein the component (B) is a reaction product obtained by hydrosilylation reaction between a hydrosilyl group-containing polysiloxane and an alkenyl group-containing organic compound, the reaction product having at least two hydrosilyl groups in its molecule.
12. The method according to claim 3 , wherein the component (D) is a propargyl alcohol and/or a maleate.
13. The method according to claim 1 , wherein the liquid resin composition comprises as a component (E) an adhesion-imparting agent.
14. The method according to claim 13 , wherein the component (E) is a silane coupling agent.
15. The method according to claim 14 , wherein the component (E) is a silane coupling agent having at least one functional group selected from an epoxy group, a methacryl group, an acryl group, an isocyanate group, an isocyanurate group, a vinyl group, and a carbamate group, and a hydrolyzable silicate group in its molecule.
16. The method according to claim 13 , wherein the component (E) is an epoxy group-containing compound.
17. The method according to claim 16 , wherein the component (E) is a polysiloxane having an epoxy group in its molecule and a polyhedral skeleton.
18. The method according to claim 9 , wherein the liquid resin composition comprises as a component (F) a cyclic siloxane compound having an alkenyl group.
19. The molded body according to claim 2 , wherein the molded body has a light transmittance of 80% or more at a wavelength of 400 nm with a thickness of 3 mm, and a change in the light transmittance at a wavelength of 400 nm after each of a test at 200±5° C. (24 hours in air) and a test using a metaling weather meter (a black panel temperature 120±5° C., an irradiance 0.53±0.05 kW/m 2 , an integrated amount of irradiated light 50 MJ/m 2 ) being 5% or less of that before each test.
20. An optodevice member using a laser in a wavelength region of 350 to 450 nm as a light source, the member comprising the molded body according to claim 2 as a main component which exhibits a gel fraction of 95% or more after immersion in toluene for 72 hours at room temperature.