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Using the the urea decomposition - uniform coprecipitation Preparation of Mg-Al layered composite metal hydroxide (Mg-Al-CO 3 -LDHs LDHs) monododecyl phosphate potassium salt ( MAPK) by a coprecipitation method, ion exchange method, and calcining the reduction method are its organic modification, to obtain an organic-modified LDHs (organic-LDHs). Analysis by X-ray diffraction (XRD), thermal gravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR) test means were characterized. Prepared by melt compounding method PP / LDHs) composites, PP / organic-LDHs and PP / organic-LDHs / zinc borate nanocomposites. X-ray diffraction, transmission electron microscopy (TEM) analysis and characterization of the structure of nanocomposites; using thermal gravimetric analysis method to study the thermal stability of the composite material; using cone calorimeter, oxygen index level - vertical burning The Tester to study the combustion properties of composite materials. Experimental results show that at a temperature of 105 ° C, the aging time 24h, nitrate and urea molar ratio of 1:3 can be prepared by well-crystallized Mg-Al-CO 3 -LDHs. TGA analysis showed that Mg-Al-CO 3 -LDHs carbonate begins to decompose at 420 ℃ and 450 ℃, the decomposition rate highest. XRD analysis showed that MAPK reduction by co-precipitation, ion exchange and calcination of the LDHs organic modification, the interlayer spacing from 0.76nm increased to 3.15nm, 3.89nm and 3.89nm. The FT-IR results of the organic-LDHs not been complete replacement of the carbonate contained in the organic-LDHs interlayer obtained by the ion exchange method, but does not exist in the structure of the two other methods to obtain the organic-LDHs carbonate. PP / organic-LDHs nanocomposites XRD analysis showed that the organic-LDHs PP composite of three preparation process, the layer spacing has increased, but the preparation process to form intercalated or exfoliated nanocomposites The structure can have a decisive impact. TEM analysis showed that the reduction of organic-LDHs of PP / ion exchange method and the PP / roasting organic-LDHs nanocomposites dispersed organic-LDHs significantly better than PP / co-precipitation method organic-LDHs nanocomposites. TGA results show that compared to pure PP, PP /-LDHs composites and PP / Organic-LDHs nano no significant change in the initial decomposition temperature of the composite material and the thermal decomposition temperature; compared to pure PP, PP /-LDHs composite material and PP / organic-LDHs nanocomposites marked increase in the amount of 600 ℃ into carbon. Cone calorimeter results show that compared to pure PP, PP /-LDHs maximum heat release rate of the composite material (PHRR) and the average mass loss rate (ALMR) substantially no change, containing a co-precipitation method, ion exchange method, the calcination reduction method organic-LDHs nanocomposites PHRR were reduced by 21%, 33%, 30%, AMLR from 15.3g/sec m2, respectively, decreased to 14.0 g / sec m2, 11.8 g / sec m2, 12.9 g / sec m2. Values ??as compared with the limiting oxygen index (LOI) of the pure PP, PP / LDHs composite material substantially constant, which contain the co-precipitation method, ion exchange method, the calcination reduction of organic-LDHs Nanocomposites LOI value corresponding increase from 17.3 large to 19.9,20.9,20.8. UL94 test results show that all material reach UL94HB level, but not meet UL94V the requirements. XRD analysis shows that the PP / organic-LDHs / zinc borate nanocomposites, PP / co-precipitation method organic-LDHs nano composite organic-LDHs layer spacing increases from 3.15nm to 3.37nm, which contain two other organic- LDHs nanocomposites XRD diffraction peaks disappeared. TEM analysis showed that PP / co-precipitation method organic-LDHs nanocomposite organic-LDHs poor dispersion, other two nano composites, organic-LDHs peel-like nanoscale lamellae dispersed in the matrix. TGA results show that the PP / LDHs composites and PP / organic-LDHs nano composite initial decomposition temperature and thermal decomposition temperature of pure PP is basically the same, there was no significant change; compared with pure PP, PP / LDHs / zinc borate complex material into carbon at 600 ℃ amount from 0.50% to 13.5%, respectively, containing total precipitation, ion exchange, the the roasting reduction of organic-LDHs PP / organic-LDHs / zinc borate nanocomposites into the charcoal increased to 11.4%, 12.1%, 12.5%. PP matrix composite cone calorimeter results show that, compared with pure PP, PP / LDHs / zinc borate composite PHRR decreased by 37% decline the ALMR from 15.3 g / sec m2 to 15.9 g / sec m2, respectively, containing coprecipitation, ion exchange method, roasting reduction of organic-LDHs PP / organic-LDHs / zinc borate nanocomposites PHRR were reduced 58%, 55%, 63%, AMLR from 15.3g/sec m2, respectively, down to 9.4 g / sec m2, 9.5 g / sec m2, 8.3 g / sec m2. Compared with the the pure PP LOI value (17.2) PP / LDHs / zinc borate composites were found to have contained coprecipitation, ion exchange method, roasting reduction of organic-LDHs PP / organic-LDHs nanocomposites LOI value 17.2 increase 19.8,20.4,20.9,21.0. The UL94 test the results show, all material reach UL94HB level, but not passed the UL94V test requirements.
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