Flame-retarding materials, 3 - Tailor-made thermal stability epoxy curing agents containing difunctional phosphoric amide groups

摘要: Four different phosphoric amides, p-phenylphosphonic diamide (2-NH2-PH), phenylphosphonicbis(N-butylamide) (2-BU-PH), phenylphosphorobis(N-butylamide) (2-BU-PHO) and phenylphosphonicbis(N-benzylamide) (2-BZ-PH), have been successfully synthesized by low temperature condensation characterized FT-IR, 1H NMR 31P NMR. These amides used to cure commercially available, unmodified, liquid epoxy resins. The curing behaviors thermal stability of the cured films studied. Comparing temperatures (initial (Ti), peak (Tp), final (Tf)) degree curing, it has observed that using agent containing bulky groups i. e., more sterically hindered structure, results in higher but a lower curing. When comparing 2-BU-PHO, which contains phenoxy group, with 2-BU-PH phenyl group back bone, is interesting note phosphorus content 2-BU-PHO (4.81%) than (4.93%), residual weight percent at 800°C (R800) also needed obtain 10% loss (T0.1) significantly for epoxies. Also from 2-BZ-PH, unlike aromatic benzyl groups, indicate aromaticity does not affect polymer film.