C 3 N 6 H 6 ·2H 3 BO 3 (M·2B)是一种极具前景的氮化硼(BN)纤维前驱体,具有环保、低成本等优点。然而,尽管在 M·2B 到 BN 的热解过程中重量损失剧烈(接近 80 wt%),为什么纤维仍能保持其形态仍不清楚。在此,在初始热解时观察到加热的 M·2B 纤维的有趣的开裂和自愈行为。原位形成的熔融氧化硼(B 2 O 3)被认为是裂缝的修复剂,随后融合到封闭三聚氰胺/三聚氰胺分子的连续基质中,随后充当氮源。乙2 O 3基质有助于在热解过程的第二个失重阶段保持纤维形态完好无损。这种利用原位形成的熔融相修复裂纹的策略为制备无缺陷的 M·2B 衍生 BN 纤维提供了详细的指导,并且对于其他陶瓷的缺陷修复具有重要意义。
A Novel B-C-N Compound Derived from Melamine Diborate
作者:Kaoru Aoki、Susumu Tanaka、Yukiko Tomitani、Masahiro Yuda、Mio Shimada、Kohei Oda
DOI:10.1246/cl.2002.112
日期:2002.1
A new B-C-N compound has been synthesized by thermal decomposition of melamine diborate mixed metal Mg powder in Ar at 1273 K. XRD revealed that the product had turbostratic structure and approximate composition of that was B1.1C1.1N1.0. Properties of the B-C-N compound obtained are discussed.
在氩气中于 1273 K 热分解三聚氰胺二硼酸盐混合金属镁粉末,合成了一种新的 B-C-N 化合物。本文讨论了所获得的 B-C-N 化合物的性质。
Supramolecular hydrogen-bonded structure of a 1:2 adduct of melamine with boric acid
作者:Abhijit Roy、Amitava Choudhury、C.N.R. Rao
DOI:10.1016/s0022-2860(02)00128-x
日期:2002.8
Boric acid (B) forms a 2:1 hydrogen-bond adduct, M(.)2B, with melamine (M), wherein, a finite tetrameric ribbon of boric acid forms hydrogen bonds with the nitrogen donor sites of M. Hydrogen-bonded layers of B and M in the bc-plane are connected by boric acid units along the a-axis to give a three dimensional structure. Interestingly. one of the amino groups of M does not participate in hydrogen bonding
硼酸 (B) 与三聚氰胺 (M) 形成 2:1 的氢键加合物 M(.)2B,其中有限的四聚硼酸带与 M 的氮供体位点形成氢键。 bc 平面中的 B 层和 M 层通过沿 a 轴的硼酸单元连接,形成三维结构。有趣的是。与 B 的所有羟基不同,M 的氨基之一不参与氢键。
Porous boron nitride coupled with CdS for adsorption–photocatalytic synergistic removal of RhB