Star‐shaped silicon‐containing arylacetylene resin based on a one‐pot synthesis using zinc powder catalysis with improved processing and thermal properties

Abstract

Herein, reporting a simple, sustainable, and cost-effective chemical synthesis of a star-shaped silicon-containing arylacetylene (SSA) resin via a one-pot process using zinc powder as a catalyst. The as-prepared viscous liquid resins exhibited moderate rheological behavior. The thermal curing temperature was determined to be 203 C using differential scanning calorimetry, which is much lower than that reported for polyimide and phthalonitrile (>300 C), indicating the SSA resins are suitable for processing at a lower temperature. Thermogravimetric analysis also revealed the excellent thermal stability and extremely high carbon residue of the cured SSA resin (the temperature at 5% mass loss and residual yield at 800 C under N 2 were 654 C and 93%, respectively). The results showed the excellent processability and thermal stability of SSA resin.

Synthesis and characterization of thermosetting polyacetylene‐terminated silicone resins

“…Whereas, the infrared absorption band of ─C≡C─ (2160 cm −1 ) groups was still observed and slightly reduced after the curing process, that is the result of the incomplete Diels-Alder reaction at internal alkyne groups. 5,28 Curing Mechanism As shown in Figure 11, the reaction temperature of each functional group is different, the hydrosilylation reaction occurs at lower temperature 29 ; the terminal alkyne is susceptible to cyclic trimerization at lower temperature similarly, and a crosslinking reaction involving the terminal alkyne (─C≡CH) groups may be responsible for the formation of a highly stable structure; the naphthalene ring and biphenyl groups are formed at higher temperature via the Diels-Alder reaction between Ph─C≡CH and ─C≡C─. The aromatic and naphthalene ring compounds usually exhibit extraordinary thermal stability of the PTS resins.…”

“…4 Over the span of few decades, there has been a growing interest in silicon-containing polymers with good overall performance in a variety of application fields such as aerospace and ceramic precursor, especially high-temperature-resistant resin matrix composites, thanks to their unique oxidation resistance, erosion resistance, and good solubility. [5][6][7] Silicon-containing aramid resins can be thermally crosslinked at high temperatures and are considered to be thermosetting materials with good heat resistance. 8,9 They can be used for dielectric sheets, broadband wave-transparency radomes, and quartz fiber composites.…”

“…Silicon provides enhanced thermal stability of the char under flame, since the silicon reaction products may remain on the surface of char and form a protective silica layer. 5,[10][11][12][13][14] Itoh et al synthesized [─Si(Ph)H─C≡C─C 6 H 4 ─C≡C─] n (MSP) resin containing silicon hydrogen bond and phenyl group by dehydrogenation coupling method using phenylsilane and mdiacetylenylbenzene (DEB) as raw materials, which had a thermal decomposition temperature of 860 C. 15 However, this resin had a high exothermic peak temperature of 210 C, and the high curing temperature will lead to shrinkage and embrittlement of the cured resin, which had defects in the preparation of composite materials. [16][17][18][19] PSA resin is a special functional resin that has excellent heat resistance and high-temperature porcelain properties by introducing silicon into aryl acetylene resin.…”

Study on vinyl crosslinking and related properties of silicon-containing arylacetylene resin synthesised by zinc powder catalysis

“…Chemical synthesis employs zinc powder on a widespread basis as a low-cost common catalyst with high catalytic efficiency. [17][18][19] Based on the substantial reducibility of zinc atom to acetenyl, 20 Shen et al successfully synthesised PSA resin by Zn powder catalysis. 21 Compared with the above three methods, the zinc powder catalytic method has the following advantages: (1) zinc powder is cheap and readily available; (2) the synthesis step is simple; (3) reaction process does not give off much heat intensively; (4) no gas release; and (5) the synthetic resin has low viscosity and excellent processing performance.…”