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A novel phosphorus-containing hyperbranched macromonomer (PHM), successfully synthesized via Michael addition polymerization of tri(acryloyloxyethyl) phosphate (TAEP) with n-butylamine (BA), was blended with epoxy acrylate resin (EA) to prepare UV curable flame retardant coatings. The study of thermal degradation of these coatings revealed that PHM can catalyze the degradation of EA, contributing to the formation of thermally stable char layer. The residues of EA3 (which contains 45 wt.% PHM) at various temperatures were analyzed by X-ray photoelectron spectroscopy (XPS) and the results displayed that the formation of phosphorus-carbon structure can well protect the carbonaceous char from thermal-oxidative degradation at 800 °C. Besides, the investigation of the flammability illustrated that the addition of PHM increased the limiting oxygen index (LOI) value and reduced the peak heat rate release (HRR) and total heat release (THR). [ABSTRACT FROM AUTHOR]

A novel phosphorus and silicon containing compound (KHPDH) has been synthesized by allowing phenyl dichlorophosphate to react with 3-triethoxysilylpropylamine and 2-hydroxyethyl acrylate (HEA). Through the sol-gel and UV-curing processes, KHPDH was incorporated into the structures of the epoxy acrylate,resulting in the formation of solid crosslinked organic/inorganic homogeneous hybrids. The solid Si NMR and DSC results demonstrate that the morphology of the mixed epoxy systems is homogeneous. The application of KHPDH as a flame retardant in epoxy acrylate not only gains satisfied flame retardancy, but also improves the hardness of epoxy acrylate. Moreover, the thermal properties of the hybrids were investigated by thermogravimetric analysis (TGA) and the thermal degradation of the materials was investigated by real time fourier transform infrared spectra (RTIR) and thermogravimetric analysis/infrared spectrometry (TG-IR). X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) were used to explore chemical components as well as the morphologies of the residual char. It was found that the silicon migrated to the surface and formed protective silicon carbide layer. [ABSTRACT FROM AUTHOR]

A novel phosphorus, nitrogen-containing compound, poly(4, 4′-diaminodiphenyl methane phenyl dichlorophosphate) (PDMPD) with high thermal stability was synthesized. The PDMPD was then incorporated into polystyrene (PS) to be used as halogen-free flame retardant. Moreover, small amounts of two boron-containing compounds, Zinc borate (ZnB) and boron phosphate (BP) were combined with PDMPD,to explore effective flame-retardant formulations for PS. The flammability and the thermal properties of the composites were evaluated using limiting oxygen index (LOI) test, microscale combustion calorimeter (MCC) and thermogravimetric analysis (TGA) respectively. A Fourier transform infrared (FTIR) spectroscopy coupled with a thermogravimetric analyzer (TG-IR) was also used to study the gas phase from the degradation of PS composites. Furthermore, the char residues of the samples were investigated by scanning electron microscopy (SEM) and FTIR. The results showed that the incorporation of PDMPD can significantly decrease the flammability of virgin PS, and enhance the thermal stability at high temperature region, in both nitrogen and air atmosphere. A combination of PDMPD with small amounts of boron compounds can further decrease the flammability. [ABSTRACT FROM AUTHOR]

UV-curable waterborne polyurethane acrylate (WPUA) modified with octavinyl polyhedral oligomeric silsesquioxane (OVPOSS) was prepared via photopolymerization between OVPOSS and WPUA. Structural and morphological features of WPUA/OVPOSS coatings were assessed using Fourier transform infrared spectroscopy, transmission electron microscopy and X-ray diffraction. Thermal properties of the WPUA/OVPOSS hybride coatings have been improved over the pure waterborne polyurethane acrylate analyzed by thermal gravimetric analysis. Performance of the coatings was also evaluated using water absorption, hardness, contact angle, X-ray photoelectron spectroscopy (XPS). The data showed that the WPUA/OVPOSS coatings possessed better water resistance and thermal oxidative stability in comparison with pure WPUA. [ABSTRACT FROM AUTHOR]