Vigilancia Tecnológica

A novel phosphorus?based compound, (oxybis(4,1?phenylene))bis((2,5?dihydroxyphenyl)(phenyl)phosphine oxide) (ODDPO?HQ), was synthesized and applied to enhance the flame retardancy of epoxy resin (EP). With a phosphorus content of 1.2 wt%, the EP/ODDPO?HQ formulation achieved a vertical burning V?0 grade and a limited oxygen index of 28.9%, while maintaining its thermal stability.AbstractA fresh phosphorus?containing fireproofing agent (oxybis(4,1?phenylene))bis((2,5?dihydroxyphenyl)(phenyl)phosphine oxide) (ODDPO?HQ) was synthesized by a simple two?step reaction. The effect of ODDPO?HQ on the glass transition temperature (Tg), crosslinking density, thermal stability, fire resistance, dielectric performances, hydrophobicity, and water absorption of epoxy resin (EP) was studied. EP/ODDPO?HQ containing 1.2?wt% phosphorus not only achieved the vertical burning V?0 grade with a limited oxygen index of 28.9% but also maintained good thermal stability. Compared to unmodified EP, its Tg value has only decreased by 7.2°C. Detailed studies revealed that the excellent flame resistance of ODDPO?HQ for epoxies was ascribed to the flame suppression both in the gaseous phase and condensed phase, especially the obvious barrier effect. Although the water uptake of the modified epoxies slightly rose with the content of ODDPO?HQ caused by the reduction of the crosslinking density within the matrix, it did not adversely affect the properties of the polymer. The modified epoxies showed reduced dielectric constant and dielectric loss values, and the contact angle of EP/ODDPO?HQ samples increased as the flame retardant content rose, which might be due to the symmetrical structure of ODDPO?HQ reducing the polarity. Our study presents an easy approach for producing high?performance epoxies.