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The synthesis of this thesis the flame retardant of a UV-curable oligomer: the cyclic phosphorus UV curable monomer (ANP). ANP and different proportions of methyl acrylate, melamine (MAPM, laboratory made), pentaerythritol triacrylate (EM235) complex prepared by UV curing intumescent flame-retardant system, the flame retardant properties of the cured film, the thermal stability and physical performance, and then to study the thermal degradation mechanisms of the cured film, combined with the expansion properties of the relationship between structure and expansion behavior in the combustion process. The specific contents are as follows: were prepared as raw materials to the reaction of neopentyl glycol acrylate phosphate (ANP), neopentyl glycol, phosphorus oxychloride, and hydroxyethyl acrylate. The use of FTIR, 1H-NMR characterization of the product of the molecular structure. Different proportions of ANP, laboratory-made of methyl acrylate, melamine (MAPM), pentaerythritol triacrylate (EM235) complex, prepared a series of ultraviolet light curable intumescent flame-retardant system, the results show that the phosphorus, nitrogen have a significant role in promoting the flame-retardant properties, not included ANP light curable coatings, flame retardant performance is poor, with increasing the ANP add the amount of light curable coatings oxygen index (LOI) values ??significantly higher, from 23.5 to 29.5. The while the Join With MAPM, the combustion process curing the spline expansion, and there are obvious synergies the ANP and MAPM between. When the ANP, MAPM, EM235 mass ratio of 35%: 25%: 40%, limiting oxygen index LOI of 29.5 and can effective expansion. TG, DTG and FT-IR study of the thermal degradation process of the cured film the the ANP, EM235/GMA and ANP/MAPM/EM235 system. The results show that: the thermal degradation of ANP of the cured film can be divided into three stages: in the range of 160 to 270 ° C, mainly phosphate and the decomposition of the ester group; within the range of 270 to 350 ° C, the main alkyl chain cleavage; 350 ℃ to 500 ℃ between structure change much; When the temperature rose to 500 ° C, aromatic group, open-loop and the formation of pyrophosphate. With the increase in the ANP levels, the initial decomposition temperature of the cured film is reduced, high temperature as the amount of carbon increases. Ester groups in the cured film EM235/GMA system thermal degradation process degrades slowly, and its alkyl degradation, degradation generates a small amount of carbon layer and can be volatile gases. The system cured film ANP/MAPM/EM235 thermal degradation is divided into three phases: the degradation of the phosphate, the degradation of the ester group, and the degradation of the melamine structure. Metaphosphoric acid in the range of 270 to 380 ° C, the generated structure rapid degradation of the ester group to generate a condensed cyclic structure in the range of 160 to 270 ° C, primarily phosphate and the decomposition of the ester group; Meanwhile, the melamine structure polycondensation generate poly triazine ring structure, accompanied by the release of a large number of noncombustible nitrogen-containing gas, these poly triazine ring structure along continued degradation to generate a nitrogen-containing gas, these nitrogen-containing gas is carbon layer parcel, and the carbon layer expansion retardant effect; no big changes in the structure between 380 ° C to 500 ℃; When the temperature rose to 500 ° C, aromatic group, open-loop and the formation of pyrophosphate. ANP, ANP/MAPM/EM235 mixture solidified carbon layer of the photo film is generated in the combustion process, the check a degree of swelling, the carbon layer strength and refractory limit research results showed that the existence of synergism between the ANP, MAPM and EM235, when flame retardant elements to the presence of an appropriate proportion, and makes a good expansion effect. In all test samples, When 0.35ANP-0.25MAPM-0.4EM235 when having a high unidirectional expansion degree and most compact carbon layer, the unidirectional degree of swelling of 7.76, carbon layer strength of 2.2 kPa, fire resistance of the highest in the 100 ℃ from 7.08 s to 37.29 s, 93.26 s to 340.04 s at 350 ℃ from IFR best performance.
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