Abstract:
T-typed bismaleimide (T-BMI) was used to blend with 4, 4'-bismaleimidodiphenylmethyene (BDM) for preparing a matrix resin with high toughness. The results show that T-BMI has great effect on improving the mechanical performances of the matrix resin. With the same mole between T-BMI and BDM, the impact strength and fracture toughness (G
IC value) of T-BMI-BDM reach up to 17.2 kJ/m
2 and 316 J/m
2, which are increased by 66.3% and 39.8% than before modifying, respectively. Furthermore, the tensile strength and flexural strength are up to 101.0 MPa and 165.0 MPa, they are improved by 12.2% and 2.5% than before modifying, respectively. The analysis of DMA and TG show that the heat-resistance and thermal stabilities of the copolymerization system are not significantly influenced by introduced T-BMI. The glass transition temperature and 5% mass loss temperature are 267.2℃ and 403.7℃, respectively. Cure condition of the matrix resin determined by DSC curves are 160℃×2 h+180℃×2 h +200×2 h+230℃×4 h. Rheological property determined by viscosity-temperature and viscosity-time curves indicates that it can be suitable for RTM process, and resin injection temperature should be selected in the range of 125℃ to 140℃.