Herein, we present the synthesis and characterization of a novel phosphorus-containing epoxy co-curing agent, ANVD, fabricated via a one-pot method utilizing vanillin, 1,5-diaminonaphthalene, and DOPO as raw materials. Structural analysis conducted through FTIR and NMR spectroscopy confirmed the composition of ANVD. Differential scanning calorimetry (DSC) results indicated ANVD has significant contribution to the curing crosslinking of DGEBA, resulting in a slightly decreased T g value for EP/ANVD compared to EP/DOPO, albeit still notably higher. Thermogravimetric analysis (TGA) revealed a reduction in the T 5% and T max values of EP/ANVD, yet ANVD’s superior char-forming ability increased char residue mass at elevated temperatures. Combustion tests showcased the outstanding flame retardancy of EP/ANVD, with EP/ANVD-5 exhibiting a limiting oxygen index (LOI) value of 33.2 % and achieving a V-0 rating in the UL-94 test. Furthermore, EP/ANVD-5 displayed a notable decrease of 38.6 % and 32.1 % in pHRR and av-HRR, respectively, compared to pure EP, surpassing EP/DOPO with equivalent phosphorus content. Analysis of decomposition products in both condensed and gas phases revealed ANVD’s role in forming dense and continuous expanded char layers during combustion, releasing phosphorus radicals and non-combustible gases, thus exhibiting dual-phase flame retardant effects. Additionally, EP/ANVD-3 exhibited enhanced mechanical properties, with tensile strength and modulus increasing from 68.5 MPa and 0.75 GPa to 76.5 MPa and 0.86 GPa, respectively, compared to pure EP. Overall, the introduction of the bio-based flame retardant ANVD presents promising opportunities for the utilization of bio-based materials in flame retardancy applications.
Aiming to address the problems of flammability and brittleness of BMI and reduce the use of petroleum-based materials, three kinds of cardanol-based co-curing agents (CDPO, CDPC, CDCP) were synthesized and applied to prepare advanced BMI . Compared to the neat BMI, the modified BMI exhibited better thermal stability with higher decomposition temperatures and char yields. The BMI/CDCP-10 containing 4.5 wt% CDCP possessed the best flame retardancy with 50.4% reduction in PHRR , 27.5% reduction in THR and 21.2% reduction in TSP compared to those of neat BMI. Moreover, with the 4.5 wt% incorporation of CDPO, CDPC and CDCP, the impact strength of BMI was enhanced by 95%, 133.8% and 127.5% respectively, due to the flexible fatty chains and the decreased crosslinking density . The reason for different modification effects among modified BMI systems is studied from the structure of modifiers, finding that the phosphorylated cardanol with higher content of O and higher valence of P can be utilized to improve the mechanical property and fire safety of BMI. This work provides a new way to reduce the dependence on the petroleum-based materials and expand the application areas of BMI.
危险品化学品经营许可证（带存储）