SiBCN是目前重要的高温非晶材料之一.非晶结构表征是研究非晶材料形成过程的关键.采用固态NMR和FT-IR为主要的研究手段研究聚硅硼碳氮烷的热稳定性和SiBCN陶瓷前驱体高温裂解机理.研究表明,陶瓷化转变过程分为三个阶段,第一阶段是产生引发剂,即聚合物前驱体中的叔碳脱氢转化成季碳自由基;第二阶段是链增长和链终止,季碳自由基首先攻击碳甲基,使甲基脱落生成新的自由基,随着温度的升高,自由基还会攻击硅甲基,生成新的自由基.在生成新的自由基过程中使链增长.当自由基与自由基结合时,链终止;第三阶段是陶瓷化,通过脱氢将已经无机化的中间产物转化成陶瓷,形成无机三维连续非晶网络.第一、二阶段属于有机转变,第三阶段属于无机转变.当转化成陶瓷时,陶瓷内只含有Si、B、C和N四种元素,端基完全脱落.
参考文献
| [1] | RIEDEL R,BILL J,KIENZLE A.Boron-modified inorganic polymers-precursors for the synthesis of multicomponent ceramics.Appl.Organgmet.Chem.,1996,10(3/4):241-256. |
| [2] | HAUG R,WEINMANN M,BILL J,et al.Plastic forming of preceramic polymers.J.Eur Ceram.Soc.,1999,19(1):1-6. |
| [3] | SCHUHMACHER J,WEINMANN M,BILL J,et al.Solid-state NMR Studies of the preparation of Si-C-N ceramics from polysilylcarbodiirnide polymers.Chem.Mater.,1998,10(12):3913-3922. |
| [4] | BERNARD S,WEINMANN M,CORNU D,et al.Preparation of high-temperature stable SiBCN fibers from tailored single source polyborosilazanes.J.Eur.Ceram.Soc.,2005,25(2/3):251-256. |
| [5] | J(A)SCHKE T,JANSEN M.Synthesis,crystal structure and spectroscopic characterization of the borazine derivatives[B {CH2(SiCl3)}NH]3 and[B{CH2(SiC12CH3)}NH]3.Zeitschriftfür anorganische und allgemeine Chemie,2004,630(2):239-243. |
| [6] | WAGNER O,JANSEN M,BALDUS H P.N(B(NMe2)2XSi(NMe2)3) (Ti(NMe2)3),[N(Si(NMe2)3)(Ti(NMe2)2)]2 und N(SiMe3) (Si(NMe2)3) (Ti(NMe2)3)-synthese und charakterisierung neuer molekularer einkomponentenvorl(a)ufer für nitridische und carbonitridische keramiken.Zeitschrift Für Anorganische und Allgemeine Chemie,1994,620(2):366-370. |
| [7] | SEYFERTH D,PLENIO H.Borasilazane polymeric precursors for borosilicon nitride.J.Am.Ceram.Soc.,1990,73(7):2131-2133. |
| [8] | SRIVASTAVA D,DUESLER E N,PAINE R T.Synthesis of silylborazines and their utilization as precursors to silicon-containing boron nitride.Eur J.Inorg.Chem,1998,(6):855-859. |
| [9] | SU K,REMSEN E E,ZANK G A,et al.Synthesis,characterization,and ceramic conversion reactions of borazine-modified hydridopolysilazanes:new polymeric precursors to silicon nitride carbide boride (SiNCB) ceramic composites.Chem.Mater.,1993,5(4):547-556. |
| [10] | WEINMANN M,HAUG R,BILL J,et al.Boron-containing polysilylcarbodi-imides:A new class of molecular precursors for Si-B-C-N ceramics.J.Organomet.Chem.,1997,541(1/2):345-353. |
| [11] | ZHOU XIAO-JUN,ZHANG GUO-JUN,LI YAO-GANG,et al.Hot pressed ZrB2-SiC-C ultra high temperature ceramics with polycar bosilane as a precursor.Mater Lett.,2007,61(4/5):960-963. |
| [12] | LI YAJING,ZHANG YUE,WANG YUSHU.Structure and oxidation behavior of high temperature ZrB2-SiBCN ceramics with polyborosilazane as a sintering additive.J.Ceram.Soc.Jpn.,2013,121(6):520-523. |
| [13] | RIEDEL R,KIENZLE A,DRESSLER W,et al.A silicoboron carbonitride ceramic stable to 2000℃.Nature,1996,382(6594):796-798. |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%