A modified polymethylsilane as the precursor for ceramic matrix composites |
| |
Authors: | Lin Liu Xin Xing Changcheng Zhou Haifeng Hu |
| |
Institution: | Key Laboratory of Ceramic Fibers and Composites, National University of Defense Technology, Changsha 410073, PR China |
| |
Abstract: | A novel SiC precursor, A-PMS, was synthesized through a reaction of polymethylsilane (PMS) with SbCl3, where the Si-H in PMS reacts with Sb-Cl to form Si-Sb bond with HCl evaporated. A-PMS was used as a precursor to prepare Cf/SiC ceramic matrix composites (CMCs) via polymer infiltration and pyrolysis (PIP) process. It is evident that SbCl3 plays a very important role in promoting chain crosslinking, transforming of the Si-Si into Si-C bonds and stabilizing PMS from very high oxidation trend of the active Si-H bonds. A-PMS keeps liquid at room temperature that is suitable for the infiltration in the absence of any solvent. A-PMS can be cured into a fully crosslinked structure at 320 °C that leads to a very high ceramic yield up to 91% and an Si/C ratio near 1.12 after pyrolysis. The resulted CMCs samples reached a density of 1.76 g cm−3 and a flexural strength of 381 MPa after only four infiltration-pyrolysis cycles. |
| |
Keywords: | Polymethylsilane Precursor Cf/SiC composites |
本文献已被 ScienceDirect 等数据库收录! |