Synthesis and Application of Novel Triazine-Based Charring-Foaming Agents in Intumescent Flame Retardant Polypropylene

Three novel triazine-based charring-foaming agents (M2-CFA, M4-CFA, and M6-CFA) were synthesized successfully with only water as the solvent and were characterized by FT-IR and thermal gravimetric analysis (TGA). These three charring-foaming agents and the byproduct 944-by were employed to study the effectiveness of the novel intumescent flame retardant dopant on the fire retardancy of polypropylene(PP) investigated through UL-94 and limiting oxygen index (LOI) tests. TGA results showed that the M4-CFA presented good char formation ability (char residue: 26.8% at 700 °C). It was found that the sample with a 2/1 mass ratio of APP to M4-CFA exhibited the best flame retardancy among all the PP composites: 35.5% LOI and a V-0 rating of UL-94. Additionally, the microstructure and morphology of char residues were further studied by XRD, Raman spectroscopy and SEM. © 2017, Tianjin University and Springer-Verlag Berlin Heidelberg.

Synthesis and Stability of Hydroxyfasudil Derivatives as Prodrugs

Fasudil (HA-1077) is the first small-molecule inhibitor of Rho-kinase and has been employed for clinical treatment of cerebral vasospasm. Hydroxyfasudil, as a metabolite of fasudil, exhibited better activity than fasudil. However, it also suffered from quick metabolisation, weak lipotropy and worse penetration of the blood–brain barrier. Thus, some hydroxyfasudil derivatives such as hydroxyfasudil acetate, hydroxyfasudil phosphate and 1-methoxyfasudil as the prodrugs of hydroxyfasudil were designed and synthesised. Meanwhile, the stability of these three compounds was also investigated. Furthermore, the reason and mechanism of hydrolysis of these compounds were discussed. This work could provide a useful guide for future research. © 2016, Tianjin University and Springer-Verlag Berlin Heidelberg.