| α-zirconium phosphate (α-ZrP) has a solid acid catalyst function. In this thesis, It would be a high efficiency flame retarding approach in polymer materials combining nanocomposites and catalyzed carbonzation on the basis of the early literatures and our group's work. Several typical polymer/OZrP nanocomposites were prepared by melting intercalation and characterized by different approaches based on the synthesis and properly organic modification ofα-ZrP. Then, the relationships between structure and property, especially thermal stability and flammability properties of the nanocomposites, using both thermogravimetric analysis (TGA) and cone calorimetry experiment, were discussed in detail. The thermal degradation of the nanocomposites was investigated by a combination of the combustion property of nanocomposites, which suggested the synergistic effect betweenα-ZrP and halogen-free flame retardants. Also, a comprehensive assessment of degradation and combustion property of the nanocomposites were carried out. The main research results as following:1. Theα-ZrP was synthesized by hydrothermal crystallization. High-intensity ultrasound was applied to the intercalation process ofα-ZrP in organic amine solution, hexadecyltrimethyl ammonium bromide(C16)/α-ZrP intercalated compound (OZrP) was obtained by "exfoliation-intercalation method". The ferrocene intercalatedα-ZrP (Fc-ZrP) was synthesized by solution method. Structures of OZrP and Fc-ZrP were characterized by X-ray diffraction (XRD). Morphologies of OZrP and Fc-ZrP were observed by transmission electron microscopy (TEM). And the thermal property of OZrP and Fc-ZrP were measured by TGA.2. LDPE/EVA/(ATH,OZrP) nanocomposites were prepared by melting interaction. It consequently exhibited better flame retardant properties than LDPE/EVA and LDPE/EVA/ATH systems. ZrP eliminated the melting-dripping phenomenon during the combustion of LDPE/EVA/(ATH,OZrP) nanocomposites and promoted formation of carbonaceous char. After evaluating peak heat release rate, ignition time(TTI), fire propagation index (FPI) and fire growth index (FGI), it indicated flame retardant properties of LDPE / EVA / (ATH, OZrP) nanocomposite had a significant improvement.3. PP/(IFR,OZrP) nanocomposites were prepared by melting interaction. TGA and SEM revealed that it had an increasing and tighter charred residue compared with PP/IFR systems or pure PP. When the PP matrix containing 25% IFR, the LOI is 33 and UL-94 is V-1 rating. When the PP matrix containing 22.5% IFR and 2.5% OZrP, the LOI is 37 and UL-94 is V-0 rating. Combined with the analysis of charred residue of nanocomposites, and ZrP was found to be a good synergistic agent in the PP/IFR flame retardant systems and eliminated dripping of PP in the combustion. ZrP promoted the cross-linking of PP chain and reduced the release of small molecules, which was proved by the formation of graphite.4. HIPS/OZrP nanocomposites were prepared by melting interaction. XRD and HRTEM confirmed that exfoliated or intercalated structures of HIPS/OZrP nanocomposites. TGA results showed that it exhibited an increasing charred residue in comparison with pure HIPS. It was found that the rate of heat release and mass loss rate were reduced by the formation of the nanocomposites from cone calorimetry. Combined with the analysis of structure and component in charred residue, there was carbon nanotubes and graphite in carbonaceous residue, then ZrP improved theflame-retardancy of HIPS by promotion the carbonization in HIPS matrix.5. The thermal stability of ABS/OZrP nanocomposites via melting interactionwas investigated by TGA. ABS/OZrP nanocomposites exhibited better thermal stability and increased charred residue than pure ABS. Carbonaceous residue of ABS/OZrP nanocomposites was analyzed by HRTEM. Carbonization mechanism was discussed, and it declared that ZrP catalyzed carbonization of ABS. This result was coincident with the formation of carbon nanotubes and graphite in carbonaceous residue of ABS/OZrP nanocomposites.
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