Molecular borosilacarbazane compounds with a fused tricyclic structure, used as precursors for heat-resistant ceramic products such as fibres, coatings, mouldings and sheet materials

摘要

Molecular borosilacarbazane compounds with a fused tricyclic structure containing two endocyclic boron atoms, one endocyclic silicon atom and three or four endocyclic nitrogen atoms, plus reactive centres on silicon and boron, are new. Molecular borosilacarbazane compounds of formula (I) are new, X1Cl, Br, I, H, amino or 1-20C hydrocarbyl; X2, X3Cl, Br, I or amino; R1C or N; R2, R3H or 1-20C hydrocarbyl, with the proviso that one of these groups is missing if R1 is N; R4H or 1-20C hydrocarbyl. Independent claims are included for (1) a method (M1) for the production of (I) by reacting compounds of formula (II) with borylsilylamines of formula HalX1X2Si-R1(R3)-BX3Hal or silylalkylboranes of formula HalX1X2Si-R1(R2R3)-BX3Hal (2) a method (M2) for the production of (I) by reacting compounds of formula (III) with borylsilylamines or silylalkylboranes as above in presence of a base, preferably a base with at least one N atom (3) a method (M3) for the production of oligomeric or polymeric borosilacarbazane compounds (P-I) by polymerisation of (I), either by heating or by reaction with compounds of formula R2R3NH (4) compounds (P-I) obtained by M3 (5) a method (M4) for the production of silicon borocarbonitride ceramics (C-I) by tempering (P-I) in an inert, ammonia- and/or amine-containing atmosphere at 20-2000[deg]C (6) ceramics obtained by M4 containing more than 93 wt% Si, N, B and C (7) a method (M5) for the production of composite ceramics of SiC, Si3N4 and BN by ageing (C-I) at above 1700[deg]C (8) composite ceramics (C-II) obtained by by crystallisation of (C-II) as in M5, containing SiC, Si3N4 and BN in homogeneous distribution. Hal : Cl, Br or I; M : lithium, sodium, potassium and/or MgHal [Image] [Image] [Image].