苯并噁嗪增韧改性双马来酰亚胺树脂的制备与研究

PREPARATION AND STUDY OF TOUGHENED BISMALEIMIDE RESIN MODIFIED BY BENZOXAZINE

未经改性的双马来酰亚胺(BMI)树脂存在着树脂溶解性差、固化成型温度高以及固化物脆性高等缺点。通过采用二烯丙基双酚A(DABPA)和3-乙炔基苯胺(m-APA)为扩链增韧剂与N,N'-(4,4'-二苯甲烷)双马来酰亚胺(BDM)共聚,双酚A型苯并噁嗪(BOZ)为共混增韧剂,得到了一种耐高温高韧性的树脂基体。采用FTIR和DSC研究了树脂体系的固化反应过程,同时进行了机械性能测试、热性能分析和显微结构分析。研究结果表明:BOZ树脂的加入能够有效提高双马树脂的韧性,在0wt%～30wt%BOZ树脂范围内,共混树脂体系固化物的冲击性能随着BOZ树脂质量分数的增加而增加,最高可达18. 3 k J/m^2,相对于BAD422体系提高了53. 8%;弯曲强度略微提升,一直保持在较高水平,最高可达到145. 9 MPa;弯曲模量随着BOZ含量的增加而有缓慢升高的趋势。然而,耐热性与热稳定性能降低,但在添加30wt%BOZ树脂时,Tg仍可达250. 8℃,初始分解温度T5%为346. 5℃,说明热性能依然较佳。

The unmodified pure bismaleimide resin has the shortcomings of poor solubility,high curing processing temperature and ease of brittleness fracture. 2,2’-Diallylbisphenol A( DABPA) and 3-aminophenylacetylene( m-APA) as chain extender toughening agent,bisphenol A phenylbenzoxazine( BOZ) as toughened agent were adopted to copolymerize with 4,4’-bismaleimidodiphenyl methane( BDM) resin. Then,a kind of resin matrix was prepared,which presented high temperature resistance and high toughness. The curing reaction of BOZ/BAD422 resin system was studied by Fourier transform-infrared spectroscopy and differential scanning calorimetry analyses,respectively. Mechanical measurements,thermal properties analysis,and microanalyses were conducted to assess the toughness and morphology of the cured blends. The research results show that the addition of BOZ resin can effectively increase the BMI resin toughness. In the range of 0 ~ 30 wt% BOZ resin,the impact performance of the blended resin system is increased with the increase of the quality fraction of BOZ resin. The maximum impact performance reaches up to 18. 3 k J/m^2,which was 53. 8% higher than the BAD422 system. The bending strength is slightly increased and remains at a high level compared with the BAD422 system,reaching at 145. 9 MPa. The bending modulus slowly increases with the increase of BOZ content. However,heat resistance and thermal stability are reduced. But glass transition temperature(Tg) can still reach 250.8 ℃ and the initial decomposition temperature( T5%) is 346.5 ℃ after the addition of 30 wt% BOZ,indicating that the thermal performance is still good.