Mechanical and dielectric properties of polyether sulfone/epoxy resin — Bismaleimide composites

In this work, 4,4'-diaminodiphenylmethane bismaleimide (MBMI) is used as matrix, epoxy resin (EP) and polyether sulfone (PES) as toughening agent, PES/EP-MBMI multi-phase composites are prepared, the composite could be applied in more fields. The results of SEM photos and energy spectrum analysis show that PES existed a strong interaction with EP-MBMI molecule and the surface of two phases is not clear and fuzzy, PES as the dispersed phase and dispersed uniformly in the PES/EP-MBMI composite. The interface among phases is blurs and exists the mutual penetration phenomenon, furthermore the cross section of the crack is rough and the direction changes, which is a typical ductile fracture morphology. The excellent performance of composite material is 4wt% PES/EP-MBMI, which has the highest flexural strength and impact strength of 144.9MPa and 19.6kJ/m
²
respectively, increasing by 41.2% and 90% compared with the EP-MBMI matrix resin. Meanwhile, the addition of PES leads to the increase of the dielectric constant and dielectric loss of the composites. Both of them increased slightly and the properties of composites are the best when the content of PES is 4wt% Overall, this study could facilitate EP-MBMI composites application in a broad range.