Preparation And Application Of Phosphorus-Containing Aqueous Intumescent Flame Retardant

With the improvement of people’s living standard, all kinds of materials are used in indoor decoration, such as foam insulation, wood based panel and others. As the same time, the fire hazard is becoming larger than before. Therefore, the research of flame retardant has related to the people’s property safety and it is important and urgent to develop as soon as possible. The intumescent flame retardant is always the research focus. At present, most of the intumescent flame retardants have a bad effect on dispersion in aqueous, which greatly limits their application fields, so the expansion of water-based flame retardant modification research has good theoretical value and application prospectsIn this paper, there are two aspects of research, which discussed about the phosphorus respectively intumescent aqueous emulsion synthesis direction and efficient intumescent flame-soluble molecules. Water-based intumescent flame retardant system is synthetically prepared water-based coating, foam or wood considerations, and a detailed study of the influence of various factors retardant properties and water-based intumescent flame retardant system in a base material. Details of the work include:(1) The addition reaction of Monomer A and Monomer B was used to produce a kind of precursor, and the PSQ emulsion was prepared by the sol-gel method of this precursor. According to the study of the solid content, emulsifier ratio, pH and other factors, we found the relationship of the particle size of PSQ emulsion with various factors, and confirmed the optimal reaction condition. Infrared (FTIR) and nuclear magnetic resonance were used to confirm the target product and functional groups. According to the scanning electron microscopy (SEM) results with the picture of transmission electron microscopy (TEM), the emulsion particle and its internal structure was analyzed and synthesized core-shell structure was found., and the constitute of the core-shell structure was analyzed by the X-ray energy dispersive spectroscopy (EDS) analysis. The P-HSi latex and water-based PU emulsion were blended and dried to obtain PU/P-HSi film with different loadings of flame retardant. Then thermal gravimetric analyzer (TGA) was used under air atmosphere or under nitrogen atmosphere to provide the information of the amount of carbon residue and thermal degradation temperature for analyzing the thermal pyrolysis conditions of the samples. Through the dynamic mechanical analyzer (DMA), the mechanical properties of the PU/P-HSi film, with different loadings of P-HSi were analyzed. The mechanical properties were lost with the loading of P-HSi, while the DMA data of 15% P-HSi content in the PU/P-HSi film can show that the P-HSi can make the mechanical properties improved by hydrogen bond. In addition, by conjunction with scanning electron microscopy (SEM) and X-ray energy dispersive spectroscopy (EDS), the flame retardant system mechanism was discussed at last.(2) We synthesized PM and explored the technology to determine the optimization program, while PU foams with different loadings of the flame retardant were used to evaluate their performances. When the amount of PM in the PU foam was more than 20%, it was too viscous to blend and foam. Surface-modified PM could solve this problem efficiently, PM-g1, PM-g2, PM-g3 and PM-g4 were synthesized in this paper. The results of scanning electron microscopy (SEM) showed that the PM-g4 was the best one of this four methods for the effect of surface-modified, then we prepared PM-g4 flame retardant polyurethane foam with different content for Oxygen Index (LOI) test and compressive strength test. The results demonstrated that the flame retardancy and mechanical performance had improved.(3) According to molecular design, the water-soluble intumescent flame retardant E (PE) was synthesized by reactant E, S and P. It is easy to dissolve in the water more than 50 degrees, pH tends to be neutral, so it can endow the flame retardant properties to the material as packing without damaging the mechanical properties. Using polyurethane foam as substrate to characterize the flame retardant, because the lack of carbon resource leaded a thin carbon layer after burning, which was easily to collapse. In order to add the carbon source, the MQ was mixed with the PE as a certain proportion to prepare a kind of aqueous flame retardants for wood impregnated, and the MQ could have a condensation on the surface of the wood to prevent the PE precipitating at room temperature. The samples had the flame retardant loading rate up to 40.3%, the corresponding LOI also increased to 30.6%, SDR 6.42.