Fiber reinforced glass matrix composites

Claim 1

A method of preparing fiber reinforced glass composites which method comprises (A) impregnating high modulus fibers with a resin sol, which resin sol is selected from the group consisting essentially of (i) a sol of an organosilsesquioxane having the average formula [C 5 H 5 SiO 3/2 ] [RSiO 3/2 ] wherein C 6 H 5 SiO 3/2 is present in said organosilsesquioxane in the amount of 5 to 100 percent by weight and RSiO 3/2 is present in the amount of 0 to 95 percent by weight based on the total weight of organosilsesquioxane present, and where R is an alkyl radical containing from 1 to 4 carbon atoms; (ii) a mixture of a sol of the organosilsesquioxane from (i) and a colloidal metal oxide, or a mixture of colloidal metal chides, selected from the group consisting of SiO 2 , Al 2 O 3 , ZrO 2 , TiO 2 , SnO 2 , ZrSiO 4 , B203, La 2 O 3 , and Sb 2 O 5 ; wherein C 6 H 5 SiO 3/2 is present in said organosilsesquioxane in the amount of 5 to 90 percent by weight and RSiO 3/2 is present in the amount of 10 to 95 percent by weight based on the total weight of organosilsesquioxane present; and (iii) a mixture of a sol of the organosilsesquioxane from (i) and a metal alkoxide, or mixture of metal alkoxides, having the general formula M(OR') x wherein M is a metal atom, R' is an alkyl radical containing from 1 to 4 carbon atoms, and x is 3 or 4, which metal alkoxide is capable of hydrolyzing and condensing in water; wherein C 6 H 5 SiO 3/2 is present in the amount of 5 to 90 percent by weight and RSiO 3/2 is present in the amount of 10 to 95 percent by weight based on the total weight of organosilsesquioxane present; (B) forming a prepreg by drying the product from (A); (C) heating the prepreg of (B) at an elevated temperature; (D) pressing the prepreg from (C) at a temperature not greater than 300°C; (E) curing the pressed prepreg from (D) at a temperature not greater than 300°C for a time sufficient to ensure complete or nearly complete cross-linking in the prepreg; (F) slowly firing the pressed and cured prepreg from (E) to a temperature of at least 1000°C in an inert atmosphere or vacuum until a fiber reinforced glass composite is obtained; and (G) cooling the fiber reinforced glass composite.

Claim 2

A method of preparing fiber reinforced glass composites which method comprises (A) impregnating high modulus fibers with a resin sol, which resin sol is selected from the group consisting essentially of (i) a sol of an organosilsesquioxane having the average formula [C 5 H 5 SiO 3/2 ] [RSiO 3/2 ] wherein C 6 H 5 SiO 3/2 is present in said organosilsesquioxane in the amount of 5 to 100 percent by weight and RSiO 3/2 is present in the amount of 0 to 95 percent by weight based on the total weight of organosilsesquioxane present, and where R is an alkyl radical containing from 1 to 4 carbon atoms; (ii) a mixture of a sol of the organosilsesquioxane from (i) and a colloidal metal oxide, or a mixture of colloidal metal chides, selected from the group consisting of SiO 2 , Al 2 O 3 , ZrO 2 , TiO 2 , SnO 2 , ZrSiO 4 , B203, La 2 O 3 , and Sb 2 O 5 ; wherein C 6 H 5 SiO 3/2 is present in said organosilsesquioxane in the amount of 5 to 90 percent by weight and RSiO 3/2 is present in the amount of 10 to 95 percent by weight based on the total weight of organosilsesquioxane present; and (iii) a mixture of a sol of the organosilsesquioxane from (i) and a metal alkoxide, or mixture of metal alkoxides, having the general formula M(OR') x wherein M is a metal atom, R' is an alkyl radical containing from 1 to 4 carbon atoms, and x is 3 or 4, which metal alkoxide is capable of hydrolyzing and condensing in water; wherein C 6 H 5 SiO 3/2 is present in the amount of 5 to 90 percent by weight and RSiO 3/2 is present in the amount of 10 to 95 percent by weight based on the total weight of organosilsesquioxane present; (B) forming a prepreg by drying the product from (A); (C) heating the prepreg of (B) at an elevated temperature; (D) pressing the prepreg from (C) at a temperature not greater than 300°C; (E) curing the pressed prepreg from (D) at a temperature not greater than 300°C for a time sufficient to ensure complete or nearly complete cross-linking in the prepreg; (F) slowly firing the pressed and cured prepreg from (E) to a temperature of at least 1000°C in an inert atmosphere or vacuum until a fiber reinforced glass composite is obtained; and (G) cooling the fiber reinforced glass composite.