聚(苯基硅烷-芳炔)树脂合成及耐高温结构形成机理

含硅芳炔树脂(PSAs)因其突出的耐热性能,在诸多领域具有应用价值。为满足高速发展的航空航天、电子信息技术的应用需求,耐高温树脂材料性能亟待提升。本研究以1,3-二乙炔基苯和苯基二氯硅烷为原料,通过格氏试剂法合成线型聚(苯基硅烷-芳炔)树脂(PPSA),对其交联固化形成耐高温结构的机理进行研究。采用差示扫描量热仪(DSC)与热重分析(TGA)对其热固化行为和热稳定性进行表征,采用傅里叶变换红外光谱仪(FTIR)和裂解气质联用(Py-GC-MS)对PPSA树脂耐高温结构的形成机理进行研究。实验证明,PPSA树脂在热固化过程中通过环三聚反应、Diels-Alder反应和硅氢加成反应生成苯环、萘环和菲环等类芳环结构,赋予了PPSA固化物优异的耐高温性能,其热分解温度(T_d5)为742-755℃,1000℃热解残留率大于92%。因此,PPSA对拓宽含硅芳炔的应用具有重要意义。

Synthesis of Linear Poly(phenylsilane-arylacetylene)Resins and Formation Mechanism of High-temperature Resistance Structure

Silicon-containing arylacetylene resins(PSAs)are promising thermal stability polymers for applications.The rapid development of aerospace and electronic information puts forward higher requirements for PSAs.Novel linear poly(phenylsilane arylacetylene)resins(PPSA)were prepared through condensation reaction of arylacetyl-Grignard reagents and phenylchlorosilane.The thermal curing behavior and thermo-stability were studied by differential scanning calorimetry(DSC)and thermogravimetric analysis(TGA).The curing mechanism was investigated by Fourier transform infrared(FTIR)and pyrolysis gas chromatography-mass spectrometry(Py GC-MS).The results revealed that phenyl,naphthyl and phenanthryl derivatives were formed by cyclotrimerization,Diels-Alder reaction and hydrosilation reaction during the curing process.The formed aromatic fused rings endowed the cured PPSA with excellent thermal stability,and the temperature at 5%weight loss(T_d5)of the cured resins ranged from 742℃ to 755℃,and the char yield at 1000℃ was above 92%.Therefore,PPSA resins are of great significance to broaden the application of PSAs.