Bismaleimide resins modified by a novel vanillin-derived allyl compounds: Synthesis, curing behavior, and thermal properties

In this study, a novel biobased allyl compound with Schiff-based structure (MPAM) was developed to improve the toughness and thermal properties of 4,4′-bismaleimidodiphenylmethane (BDM). The chemical structure of MPAM was characterized by Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance ( 1 H NMR). A series of BDM/DBA-MPAM blend resins (BD-MPAM resins) were prepared by adjusting the mass ratio of BDM + DBA (BD) to MPAM. The effects of MPAM content on the curing behavior, thermal and mechanical properties of BD-MPAM resins were discussed in details. Compared with BD resin, the thermal stability of modified resins was improved by increasing the content of MPAM. Meanwhile, an increase of 37.1% in flexural strength, and 228 MPa in flexural modulus were obtained for the cured BD-MPAM resin having 10 wt% MPAM loading compared to the BD resin. The impact strength of BD-10 wt% MPAM is of the maximum value (6.6 kJ/m 2 ). Finally, the fracture surface morphology of the BD-MPAM resins was studied by the scanning electron microscope (SEM).