| The different properties of coatings will produce various effects during its application process. Although polyurethane (PU) coatings are widely used in industrial and architectural fields for its excellent oil resistance, anti-corrosion property and strong adhesion ability, the poor fire resistance of PU coatings has hindered its further application.The fire-retardant PU coatings were developed by means of adding the synthesized intumescent flame retardant. The structure, property and mechanism of the corresponding flame retardant were studied thoroughly. The heat conduction behavior of the fire-retardant PU coatings was analyzed on the basis of proposed flame retardant model. A novel triazine polymer char-forming agent was synthesized successfully by using cyanuric chloride as raw material. The structure and composition of the synthesized char-forming agent were characterized by means of FTIR, MAS-NMR13C and ELA. The results showed that the char-forming agent was a dimer of triazine circle, amine group and ethanolamine. The investigation also indicated that the synthesized char-forming agent has excellent thermal stability as well as high melting point and can't dissolve in normal solvent.In this article it is dealed with synthesis and characterization of the carbonific. Two steps were used in synthesis process and the structure was characterized by Fourier transform infrared spectroscopy (FTIR), magic-angle spinning nuclear magnetic resonance (MAS-NMR13C) spectroscopy, elemental analysis(ELA)and end-group analysis. Results show that structure of the carbonific was composed of triazine ring, amido and ethanolamine groups.Meanwhile, properties such as density, melting point,DSC and thermal stability of the carbonific are tested. In the following part, a sole IFR additive was obtained after four steps of synthesis process including the steps of synthesis of the carbonific.Also,the structure was characterized by FTIR, MAS-NMR 13C spectroscopy and ELA. Results show that structure of the IFR agent was made up of the carbonific and pentaerythritol ramification. Finally, properties of the IFR agent are discussed.The addition of ammonium-polyphosphate (APP) and the carbonific into PU varnish leads to a great improvement in its carbonization and FR performances.So,after choosing the most effective combination of APP, carbonific and PU varnish (APP/ Carbonific/PU varnish=15:5:80), this paper deals with the evaluation of characteristic performances such as FR property, thermal stability of IFR/PU-based coatings, rheology of IFR/PU-based coating solutions and mechanical properties such as har dricss, adhesion, flexibility of IFR/PU-based dry coating films. Meanwhile, the addition oh the 1FR agent (20% Wt) into PU coating also increases FR properties of the coatings. Then , the same properties similar to the APP/carbonific/PU-based coatings are characterized.Results of research made on the physics and chemistry properties of FR coating solution show that 0.4% (Wt) silane coupling agent and 1%(Wt) bentonite can improve fluidity, thixotropy and store stability properties of the two systems. FR mechanism of the above two systems is discussed. Thorough research is made on APP/Carbonific/PUsystem. Based on results of thermogravimetric analysis(TGA),thermal degradation of the system is divided into five steps. Each step is characterized by SEM, FTIR, MAS-NMR13C and ELA. Results show that FR mechanism of this system is based on the intumescent and porous char. This char is made up at least of three types of materials. One comes from the degradation product of PU polymers,the second comes from reaction product of the degradation product of PU and APP and the third comes from the esters formed by degradation product of APP and the carbonific. Also, TGA and FTIR are used to research on the FR mechanism of IFR/PU system and results also show that amine, aromatic products and phosphoric esters are combined in the intumescent char to make the coating system have FR property.
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