Abstract: Circuit subassemblies comprising a conductive layer disposed on a dielectric substrate layer, wherein the dielectric substrate layer comprises a crosslinked fluoropolymer.

Abstract: This invention pertains to a siloxane resin composition comprising R1SiO3/2 siloxane units, R2SiO3/2 siloxane units and (R3O)bSiO(4-b)/2 siloxane units wherein R1 is an alkyl group having 1 to 5 carbons, hydrogen, or mixtures thereof; R2 is a monovalent organic group having 6 to 30 carbons; R3 is a branched alkyl group having 3 to 30 carbons, b is from 1 to 3; and the siloxane resin contains from 2.5 to 85 mole percent R1SiO3/2 units, 2.5 to 50 mole percent R2SiO3/2 units and 5 to 95 mole percent (R3O)bSiO(4-b)/2 units. The siloxane resin is useful to make insoluble porous resin and insoluble porous coatings. Heating a substrate coated with the siloxane resin at a sufficient temperature effects removal of the R2 and R3O groups to form an insoluble insoluble porous coating having a porosity of 1 to 60 volume percent and a dielectric constant in the range of 1.5 to 3.0.

Abstract: This invention pertains to a siloxane resin composition comprising R1SiO3/2 siloxane units, R2SiO3/2 siloxane units and (R3O)bSiO(4-b)/2 siloxane units wherein R1 is an alkyl group having 1 to 5 carbons, hydrogen, or mixtures thereof; R2 is a monovalent organic group having 6 to 30 carbons; R3 is a branched alkyl group having 3 to 30 carbons, b is from 1 to 3; and the siloxane resin contains from 2.5 to 85 mole percent R1SiO3/2 units, 2.5 to 50 mole percent R2SiO3/2 units and 5 to 95 mole percent (R3O)bSiO(4-b)/2 units. The siloxane resin is useful to make insoluble porous resin and insoluble porous coatings. Heating a substrate coated with the siloxane resin at a sufficient temperature effects removal of the R2 and R3O groups to form an insoluble insoluble porous coating having a porosity of 1 to 60 volume percent and a dielectric constant in the range of 1.5 to 3.0.

Abstract: Silicone resins comprising 5 to 50 mole % of (PhSiO(3-x)/2(OH)x) units and 50 to 95 mole % (HSiO(3-x)/2(OH)x), where Ph is a phenyl group, x has a value of 0, 1 or 2 and wherein the cured silicone resin has a critical surface free energy of 30 dynes/cm or higher. These resins are useful as etch stop layers for organic dielectric materials having a critical surface free energy of 40 dynes/cm or higher.

Abstract: This invention pertains to a siloxane resin composition comprising R1SiO3/2 siloxane units and (R2O)bSiO(4−b)/2 siloxane units wherein R1 is an alkyl group having 1 to 5 carbons; R2 is a branched alkyl group having 3 to 30 carbons, b is from 1 to 3. The siloxane resin contains a molar ratio of R1SiO3/2 units to (R2O)bSiO(4−b)/2 units of 1:99 to 99:1. The siloxane resin is useful to make insoluble porous resins and insoluble porous coatings. Heating a substrate coated with the siloxane resin at a sufficient temperature effects removal of the R2O groups to form an an insoluble porous coating having a a dielectric constant in the range of 2.1 to 3, a porosity in the range of 2 to 40 volume percent and a modulus in the range of 1.9 to 20 GPa.

Abstract: This invention pertains to a siloxane resin composition comprising HSiO3/2 siloxane units, and (R2O)bSiO(4-b)/2 siloxane units wherein R2 is independently selected from the group consisting of branched alkyl groups having 3 to 30 carbon atoms and substituted branched alkyl groups having 3 to 30 carbon atoms, b is from 1 to 3. The siloxane resin contains a molar ratio of HSiO3/2 units to (R2O)bSiO(4-b)/2 units of 0.5:99.5 to 99.5. The siloxane resin is useful to make insoluble porous resins and insoluble porous coatings. Heating a substrate with the siloxane resin at a sufficient temperature effects removal of the R2O groups to form an insoluble porous coating having a porosity in a range of 1 to 40 volume percent and a modulus in the range of 4 to 80 GPa.

Abstract: A polymer matrix composite comprises a matrix of a cured methylsilsesquioxane resin and a reinforcing material. The composite has low heat release rate, smoke yield, and carbon monoxide yield when burned. After burning, the composite has high char yield and retains much of its initial tensile strength. The method for making the composite comprises applying a silanol-functional methylsilsesquioxane resin comprising 70 to 90 mol % ((CH.sub.3)SiO.sub.3/2) units and 10 to 25 mol % (CH.sub.3 Si(OH)0.sub.2/2) units to a reinforcing material and curing the resin.