Synthesis and flame retardant testing of new boronated and phosphonated aromatic compounds
作者:Vladimir Benin、Sravanthi Durganala、Alexander B. Morgan
DOI:10.1039/c1jm14682c
日期:——
The present report describes the preparation and use of some dimethyl terephthalate derivatives in transition metal-catalyzed coupling reactions to produce new reactive flame retardants. Dimethyl iodoterephthalate and dimethyl 2,5-diiodoterephthalate were successfully employed in the preparation of phosphonic and boronic esters and acids. The latter were tested for heat release with a microcombustion calorimeter (ASTM D7309) to determine the potential for heat release reduction of these flame retardant molecules. The results showed that the addition of boronic or phosphonic acids greatly lowered the heat release, due to a condensed phase (char formation) mechanism. Adding ester groups to the boronic acids or phosphonic acids could either completely remove all flame retardant effects or make the molecule act more like a vapor phase flame retardant. Finally, the various potential flame retardants were solvent blended with a thermoplastic polyurethane to assess their flammability reduction effects by microcombustion calorimetry. The results of these experiments found that the molecules that reduced heat release the most by themselves showed the greatest reduction in heat release in a polyurethane as well, with the boronic acids yielding the greatest reduction in heat release.
本报告介绍了在过渡金属催化的偶联反应中制备和使用一些对苯二甲酸二甲酯衍生物来生产新型活性阻燃剂的情况。碘对苯二甲酸二甲酯和 2,5-二碘对苯二甲酸二甲酯被成功用于制备膦酸和硼酸。使用微燃烧量热仪(ASTM D7309)对后者进行了热释放测试,以确定这些阻燃剂分子减少热释放的潜力。结果表明,添加硼酸或膦酸可大大降低热释放,这是由于凝聚相(炭形成)机制所致。在硼酸或膦酸中加入酯基,可以完全消除所有阻燃效果,或者使分子的作用更像气相阻燃剂。最后,将各种潜在的阻燃剂与热塑性聚氨酯进行溶剂混合,通过微燃烧量热法评估其降低可燃性的效果。这些实验的结果表明,本身最能减少热释放的分子在聚氨酯中也能最大程度地减少热释放,其中硼酸能最大程度地减少热释放。