Amorphous SiCO and crystalline SiC fibers form curable alk-1-enyl ether functional siloxane resins

摘要

The present invention teaches a method for preparing a ceramic fiber and comprises (A) forming a green fiber from an alk-1-enyl ether functional siloxane resin of the general formula (R¹SiO_3/2)_q(R²SiO_3/2)_r-(R¹_wR²_xRSiO_(3-w-x)/2)_s(R¹_wR²_xR³SiO_(3-w-x)/2)_t wherein R is an alk-1-enyl ether group; each R¹ is selected from an aryl group having from 6 to 10 carbon atoms; each R² is selected from an alkyl group having from 1 to 4 carbon atoms; R³ is an alkenyl group having from 2 to 10 carbon atoms; w has a value of 0, 1 or 2; x has a value of 0, 1 or 2 with the provisio that w + x ≤ 2; q has a value of 0 to 0.98; r has a value of 0 to 0.98; s is greater than zero; t ≥ 0; s + t = 0.02 to 0.5 and q + r + s + t = 1; (B) curing the green fiber to render it non-fusible; and (C) heating the non-fusible fiber in an inert environment to a temperature of at least 800°C. to convert it to a ceramic fiber.