A method of preparing silazane polymers, with 3 or more repeating units, of the general formula
and a (CH3)2NH byproduct group where R is
hydrogen, an alkyl group having 1-6 carbon atoms or
an aryl group having 6-12 carbon atoms, a = 0, or 1,
b = 2-4, c = 0-2, d = 0 or 1, e = 0-2, f = 0-2, g =1-3 and
a+c+e+f+g=4 for the polymer units; and R' is hydrogen or methyl, whereby the silazane polymer is substantially free of halide impuriites by transaminating an aminosilane of the general formula (R)a((CH3)2N) bHcS with an amine of the general formula (CH3)dNH3-d; the amine has a molecular weight lower than 45; all in the presence of an acid catalyst or the ammonium salt of the acid and thereafter condensing to form the polymer. Silicon nitride or silicon nitride containing ceramics. are produced by pyrrolizing the silazane polymers.
一种具有 3 个或更多重复单元的
硅烷聚合物的制备方法,其通式为
和一个 (
CH3)2NH 副产物基团,其中 R 是
氢、1-6 个碳原子的烷基或
具有 6-12 个碳原子的芳基,a = 0 或 1、
b = 2-4,c = 0-2,d = 0 或 1,e = 0-2,f = 0-2,g =1-3,以及
a+c+e+f+g=4 为聚合物单元;R'为氢或甲基,其中
硅氮烷聚合物基本上不含卤化物,其方法是将通式为 (R)a(( )2N) bHcS 的
氨基
硅烷与通式为 ( )dNH3-d 的胺(胺的分子量低于 45)进行反式胺化,然后在酸催化剂或酸的
铵盐存在下缩合形成聚合物。
氮化硅或含
氮化硅的陶瓷是通过
吡咯烷化
硅氮烷聚合物生产的。