苯并噁嗪改性硅炔树脂固化行为及性能

Curing Behaviour and Properties of Silkyne Resins Modified with BZ-BPA

通过含氰基和乙炔基的苯并噁嗪(BZ-BPA)改性聚(间二乙炔基苯一甲基氢硅烷)(PSA)制备了一系列BP共混树脂。采用傅里叶变换红外光谱、旋转流变仪、差示扫描量热分析、热重分析法分析了BP共混树脂的固化行为,结果表明,噁嗪环、硅氢键、端乙炔基、内乙炔基及氰基等活性基团均参与了固化反应。BP-3固化物在N_(2)和空气中热失重5%的温度(T_(d5))及1000℃质量保留率分别为687.3℃,92.1%和582.4℃,26.5%。石英纤维增强BP树脂复合材料(QF/BP)的力学性能和耐热性能测试结果显示,常温下弯曲强度从153.5 MPa提高至300.4 MPa、层剪剪切强度从21.6 MPa提高至35.6 MPa;400℃热氧化2 h后,QF/BP复合材料的力学强度保留率高于60%,600℃热氧化15 min后树脂结构已遭破坏;QF/BP-3的玻璃化转变温度(Tg)超过500℃。以上结果表明,BP共混树脂及其复合材料具有优异的耐热性能,力学性能有所提升。

A series of BP resins were prepared by modifying poly(m-diethynylbenzene monomethylhydrosilane)(PSA)with benzoxazine(BZ-BPA)containing cyano and acetylene group.The curing behaviour of the BP blended resins was analyzed by Fourier transform infrared spectroscopy(FT-IR),rotational rheometry,differential scanning calorimetry(DSC)and thermogravimetric analysis(TGA).The results show that the reactive groups such as oxazine ring,silicone hydrogen bond,terminal acetylene group,internal acetylene group and cyano group were involved in the curing reaction.The 5%thermal mass loss of the BP-3 blended resin in N_(2) and air(T_(d5))and mass retention at 1000℃are 687.3℃,92.1%and 582.4℃,26.5%,respectively.The mechanical and thermal properties of the quartz fibre reinforced BP resin composites(QF/BP)show that the flexural strength of the QF/BP composites is increased from 153.5 MPa to 300.4 MPa and the interlaminar shear strength increased from 21.6 MPa to 35.6 MPa;the mechanical strength retention of the QF/BP composites is higher than 60%after 2 h of thermal oxidation at 400℃;the glass transition temperature(Tg)of QF/BP-3 exceeds 500℃.These results indicate that the BP blended resin and its composites have excellent thermal properties and improved mechanical properties.