Polyzirconosilane Preceramic Resin as Single Source Precursor of SiC–ZrC Ceramics

Wang, Mingcun; Huang, Chuanjin; Wang, ‪Zhehui

doi:10.1007/s10904-015-0278-2

Cited by 7 publications

(3 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…An oligosilylnitrile resin was prepared by Wurtz–Fittig reduction condensation using the similar procedure reported in the literature. , In a three-necked flask equipped with a flux condenser and an addition funnel, the reductant of lithium (5.6 g, 0.8 mol) was first added in 100 mL of THF, and the air in the flask was blown out by nitrogen flow. After the reaction temperature reached 50 °C, the mixture of methyldichlorosilane (0.2 mol, 23 g), 4-bromophthalonitrile (0.2 mol, 36.4 g), and 2,5-dichlorobenzonitrile (0.1 mol, 17.2 g) in 100 mL of THF was added dropwise for about 120 min while the reaction temperature was maintained below 60 °C.…”

Section: Methodsmentioning

confidence: 99%

“…The synthesis of oligosilylarylnitrile is via a Wurtz–Fittig protocol using lithium as a reductant in the Lewis base-type good solvent of tetrahydrofuran (THF). By such synthetic method, the coupling condensates from aromatic halide were successfully prepared and a series of polysilanes were also prepared from chlorosilanes. , On the basis of the experienced synthesis, oligosilylarylnitrile in this paper was readily synthesized using methyldichlorosilane, 4-bromophthalonitrile, and 2,5-dichlorobenzonitrile as starting chemicals.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Oligosilylarylnitrile: The Thermoresistant Thermosetting Resin with High Comprehensive Properties

Wang

2018

ACS Appl. Mater. Interfaces

Self Cite

View full text Add to dashboard Cite

One of the highest thermoresistant thermosetting resins ever studied so far, oligosilylarylnitrile resin, was investigated first in this study. Oligosilylarylnitrile was synthesized by lithium-reduced Wurtz-Fittig condensation reaction, and the prepared viscous resin exhibited moderate rheological behaviors while heated purely or together with 20% polysilazane as a cross-linking agent. The thermal curing temperatures were found by differential scanning calorimetry at 268 °C (pure) and 158 °C (with the polysilazane cross-linking agent), which is comparably close to that of polysilylarylacetylene resin (normally at 220-250 °C) but much lower than those of polyimide and phthalonitrile resins (normally >300 °C), indicating the admirable material processability of oligosilylnitrile. The cured oligosilylarylnitrile resins have extremely high thermal resistance, indicated by the results of thermogravimetric analysis (the mass residue at 800 °C is >90% under N) and dynamic mechanical analysis (the glass-transition temperature is >420 °C). The mechanical property of the oligosilylarylnitrile-matrixed silica-cloth reinforced laminate is comparably close to those of polyimide and phthalonitrile but much higher than that of polysilylarylacetylene, indicating the enviable thermal and mechanical properties of oligosilylnitrile. Thus, among the high-temperature resins ever studied so far, the oligosilylarylnitrile resin was found to have the almost best comprehensive characteristics of processability and properties.

show abstract

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Oligosilylarylnitrile: The Thermoresistant Thermosetting Resin with High Comprehensive Properties

Wang

2018

ACS Appl. Mater. Interfaces

Self Cite

View full text Add to dashboard Cite

show abstract

“…with the liquid precursor itself acting as a mutual solvent. The precursors are dried and cured at relatively low temperatures and then heated at high temperatures to complete the carbothermal reduction reaction to form HTC-SiC composite powders, such as ZrC-SiC, ZrB 2 -SiC, and HfB 2 -SiC, etc [25][26][27][28][29][30]…”

mentioning

confidence: 99%

Preparation of Ultra-High Temperature Ceramics–Based Materials by Sol-Gel Routes

Li¹,

Huang²,

Zhang³

2017

Recent Applications in Sol-Gel Synthesis

View full text Add to dashboard Cite

Ultra-high temperature ceramics (UHTCs) are a class of inorganic materials that have melting point over 3000°C and are typically borides, carbides, and nitrides of early transition metals. UHTCs are considered as the promising candidate used in the extreme environment involved with the hypersonic aviation thermal protective system. Synthesis of UHTCbased materials can be divided into solid-based and solution-based protocols according to the state of the raw materials. A sol-gel technique is one of the solution-based protocols for the preparation of UHTC-based materials, which involves the hydrolysis, condensation of the metal organic and/or metal inorganic compounds, gelation, and the posthigh temperature treatment of the dried gels. The sol-gel technique enables the synthesis of UHTC-based materials at 1300-1600°C. UHTC-based materials with desired shapes, such as nanopowders, fibers, and porous monoliths, can also be prepared via sol-gel routes.Recent interest in UHTCs has been motivated by the search for materials that can withstand extreme environments, such as extreme temperature, chemically aggressive environments, and rapid heating/cooling, etc. [5,6]. Due to the combination of series of excellent physical and chemical properties, such as high hardness, good high temperature stability, and excellent solid-phase stability, UHTCs are considered as promising candidates for a variety of high-temperature structural applications, including engines, hypersonic vehicles, plasma arc electrode, cutting tools, furnace elements, and high temperature shielding. However, owing to the strong covalent bond and relatively low volume diffusion coefficient, UHTCs are difficult to get successfully sintered. Densification of these materials is typically performed by hot pressing and spark plasma sintering with or without sintering aids.UHTCs can be synthesized by a variety of routes, which can be divided into solid phase protocols and solution based protocols based on the state of the starting materials [7,8]. Among the solid-phase protocols, transition metal oxides, carbon black, boron oxide, and boron carbide are commonly used as the starting materials. After ball-milling and high temperature carbothermal reduction, the mixtures are converted into UHTC powders. Examples of the reactions used to synthesize borides and carbides are listed in Table 1 [7]. These reactions are written for ZrB 2 and ZrC, but analogous processes produce other borides and carbides. These solid phase protocols are very straightforward and simple and are used to produce UHTC powders commercially. However, due to the heterogeneity of the reactants, the reactions need to be performed at high temperatures for several hours to complete. Also, those synthesized UHTC powders are micron-sized particles. Figure 1. A comparison of the melting temperatures of the most refractory members of several classes of materials.

show abstract

A thermoset hybrid sol for the syntheses of zirconium carbide–silicon carbide foam via replica method

Bao

et al. 2018

J Porous Mater

View full text Add to dashboard Cite

Polyzirconosilane Preceramic Resin as Single Source Precursor of SiC–ZrC Ceramics

Cited by 7 publications

References 12 publications

Oligosilylarylnitrile: The Thermoresistant Thermosetting Resin with High Comprehensive Properties

Oligosilylarylnitrile: The Thermoresistant Thermosetting Resin with High Comprehensive Properties

Preparation of Ultra-High Temperature Ceramics–Based Materials by Sol-Gel Routes

A thermoset hybrid sol for the syntheses of zirconium carbide–silicon carbide foam via replica method

Contact Info

Product

Resources

About