High-temperature-resistant polycarbosilane precursor and preparation method thereof

By introducing Al(OH)3 and zirconium organic precursors into the precursors of silicon carbide fibers, and using the high-temperature and high-pressure dissolution of CO2 gas, the problem of insufficient heat resistance of silicon carbide fibers was solved, and carbonized fibers with excellent high-temperature properties were prepared. Silicon fiber meets the high-temperature mechanical performance requirements of aircraft and other fields.

CN109824905AActive Publication Date: 2019-05-31JIANGXI XINDA HANGKE NEW MATERIAL TECH CO LTD
10 Cites 5 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Filing Date
2019-01-28
Publication Date
2019-05-31

AI Technical Summary

Technical Problem

The heat resistance of existing silicon carbide fibers is insufficient, especially in high-temperature environments above 2000°C, making it difficult to meet the high-temperature mechanical performance requirements of aircraft and other fields.

Method used

Polydimethylsilane (PDMS) is used as the raw material, Al(OH)3 is introduced into it, and it is calcined at high temperature to generate nanoscale γ-Al2O3, which is then added to the PDMS decomposition product, and then a zirconium-containing organic precursor is introduced , during the high-temperature sintering process, the high-temperature and high-pressure dissolution promotion effect of CO2 gas is used to prevent the growth of Al2O3 grains, thereby preparing silicon carbide fibers with good high-temperature properties.

Benefits of technology

The prepared silicon carbide fiber has high strength, good high temperature resistance, high ceramic conversion rate, high content of foreign elements, narrow molecular weight distribution, and excellent overall performance.

✦ Generated by Eureka AI based on patent content.
Patent Text Reader

Abstract

The invention relates to a high-temperature-resistant polycarbosilane precursor and a preparation method thereof. Al(OH)3 is introduced into PDMS (polydimethylsiloxane) acting as a raw material; Al(OH)3 is calcined at a high temperature to obtain nano gamma-Al2O3 having a particle size of 5-10 nm; the nano gamma-Al2O3 is subjected to addition substitution with the PDMS decomposition product; a zirconium-bearing organic precursor is added into the system; Zr can prevent growth of Al2O3 grains during high temperature sintering, so that silicon carbide fibers with good high temperature performance are prepared. Specifically, refractory metals are introduced to a precursor, so that a silicon carbide fiber precursor prepared has high heterogeneous element content, narrow molecular weight distribution, good spinnability and high ceramic conversion rate; silicon carbide fibers prepared with the precursor herein have high strength, good high temperature resistance and excellent integrated performance. In addition, since CO2 gas can promote dissolution of a mixed polymer under high temperature and high pressure, reactive heat transfer is more uniform and reaction is more thorough.
Need to check novelty before this filing date? Find Prior Art