Preparation And Performance Study Of Phosphorus-containing Intrinsic Flame Retardant Polyester

In this thesis, various polymers including oil-based phosphorus-containing flame retardant alkyd resin, waterborne phosphorus-containing flame retardant alkyd resin, phosphorus-containing flame retardant polyester were prepared through introducing the element phosphorus into the polymer chains. Using the nano silicon dioxide that was beforehand worked by silane coupling agent modified polyester, finally flame retardant nanocomposite was obtained. The structure of the phosphorus-containing polymers, thermal stability, char formation ability, flame resistance and so on were investigated by Fourier transform infrared (FTIR) analysis, Thermogravimetric analysis (TGA), limit oxygen index (LOI), vertical combustion experiment (UL94), Scanning electron microscope (SEM), elemental analysis (EDS).Using synthetic9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide-maleic anhydride (DOPOMA), bean oleic acid as raw materials to prepare the oil-based/waterborne phosphorus-containing flame retardant alkyd resins, which presented excellent properties of film adhesion, impact strength and hardness. Through the experiment, the results showed that the optimum esterification temperature of synthesis of the oil-based alkyd resin was controlled between210℃and220℃, the best reaction time was4.5h. Choosing this way that compound oil-based driers and triethanolamine were put into the system before neutralization reaction could make the waterborne alkyd resin coatings had good mechanical properties. Through TGA and LOI experiments, the results showed that the temperature of initial decomposition of the oil-based/waterborne phosphorus-containing flame retardant alkyd resins firstly increased and then descend with the increase of phosphorus content under nitrogen; the ultimate amount of carbon residue increased, but also the LOI increased.DOPOMA and glycol as raw materials were used to prepare the phosphorus-containing flame retardant polyester materials and nanocomposite materials that the nano silicon dioxide beforehand worked by silane coupling agent was brought into polyesters. The mechanics experiment showed that the tensile and bending strength of polyester materials firstly increased and then descend with the increase of phosphorus content. When the phosphorus content was2%, tensile and bending strength reached the maximum, respectively were23MPa,37MPa. Through TGA, LOI and SEM experiments, the results showed that the temperature of initial decomposition of polyester materials and nanocomposite firstly increased and then descend with the increase of phosphorus content, the char formation ability and flame resistance (LOI) were greatly improved; the addition of nano silicon dioxide also could enhance the carbon ability of materials. SEM showed that the carbon after combustion could form continuous and compact porous microstructure.