The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/mame.201800713. High Performance ResinsA new kind of high performance bismaleimide resin with good processability and improved toughness is synthesized by chemical modification of 4,4′bismaleimidodiphenylmethane (BMI) by eugenol (EG) and different contents of 4,4′-diphenylmethane diisocyanate (MDI). MDI-EG-BMI resins exhibit good thermal stability for its 5% weight loss temperatures around 300 °C and its residue of 41.61% at 900 °C, which are much higher than those of EG-BMI resin. Then, the carbon fiber-reinforced MDI-EG-BMI composites are fabricated. The mechanical properties of the composites matrixed by MDI-EG-BMI resins are better than those by EG-BMI resin. For carbon/MDI-EG-BMI composites, their glass transition temperatures are higher than 300 °C, and their flexural strength, moduli, and toughness are maintained at a range of 217.47-404.36 MPa, 35.12-48.49 GPa, and 1.16-2.63 MJ m −3 respectively; with the contents increasing of MDI in the resin formulation, the flexural properties first increase then decrease; comprehensively the composite with 30 wt% MDI has the best mechanical and thermal properties.

Hydroxymethylated eugenol (MEG) and poly (hydroxymethylated eugenol) (PMEG) were synthesized by the condensation reaction of eugenol (EG) with formaldehyde. The different contents of MEG and PMEG were used to modify 4,4 0-bismaleimidediphenylmethane (BMI). The cured MEG-BMI resins exhibit good thermal stability evidenced by its 5% weight loss temperatures above 407 C and its residue above 39.4% at 800 C under nitrogen. For carbon/MEG-BMI composites, their glass transition temperatures were around 400 C; their flexural strength and moduli were maintained at a range of 488.87-575.47 MPa and 48.84-60.26 GPa, respectively. With the increasing content of BMI in the resin formulation, the flexural properties decreased; comprehensively the composite with the eugenol/maleimide unit ratio (1:0.3 mol) had the best mechanical and thermal properties, meanwhile its renewable carbon content was as high as 57.80%. As a new candidate of high temperature thermosetting resin, MEG would find promising applications for advanced composites' matrice.

Eugenol (EG) is an abundant renewable compound that has been widely used in the synthesis of bio‐based thermosetting resin, but there are few reports on the phthalonitrile (PN) resin derived from EG. In this study, a new kind of bio‐based PN resin (MEG‐PN) derived from EG derivative was successfully synthesized. PN is a traditional class of high‐performance thermosets with poor processability for its ultra‐high melting point and curing temperature. The MEG‐PN resin possesses excellent processability: its melting temperature is much lower (77°C), and it can be cured at a moderate temperature (281°C) in the absence of curing agents. The cured MEG‐PN resin exhibited great heat resistance according to its 5% weight loss temperature at 448°C and its char yield percentage as high as 75.6% at 800°C under nitrogen. The properties of the carbon‐fiber reinforced MEG‐PN composite were comparable to those of petroleum‐based PN resins: the glass transition temperature was around 397°C; the flexural strength and modulus were as high as 756 MPa and 119 GPa, respectively. Overall, a bio‐based PN thermoset with great comprehensive performance was synthesized possessing the potential in the application of advanced composite.