The Preparation And Properties Of Flame Retardant PBT And Its Alloys/Clay Nanocomposites

Poly(butylene terephthalate) (PBT) is an important semicrystalline engineering thermoplastic with many valuable properties including a high rate of crystallization, good solvent resistance, thermal stability, and excellent processing properties. However, pure PBT has high combustibility, low impact strength and heat distortion temperature. Based on the investigation of a lot of literatures and the relative work in our research group, the recent progress about modification of PBT resin including flame retardancy of PBT, polymer/clay nanocomposites (PCN) and PBT alloys is reviewed in this dissertation. In order to improve the flame retardancy, mechanical and thermal properties of PBT, the factors on the all-round performances of PBT were discussed in detail and the design project of the flame retardant PBT alloy nanocomposites was optimized. Firstly, Co-addition of melamine (MA) and triphenyl phosphate (TPP) could achieve the need of non-halogen flame retarded PBT. The structure and thermal properties of the flame retarded PBT and the mechanism of flame retardant action were studied by SEM, DSC, TGA, dynamic FTIR and pyrolysis/GC/MS. To match the high processing temperature of PBT, we employed cetyl pyridium chloride (CPC) to prepare the high thermally stable organic-modified montmorillonite (OMT_cpc); and then prepared PBT/OMT_cpc nanocomposites by direct melt intercalation, and the correlation between microstructure and thermal properties of PBT/OMT_cpc nanocomposites was studied. To reduce the tedious process of clay modification, montmorillonite (MMT) and CPC were mixed and ground together in a pestle and mortar, and then were melt-mixed with PBT to successfully prepare PBT/MMT/CPC nanocomposites. The effect of the proportion of CPC relative to MMT on the morphology and properties of PBT/MMT/CPC nanocomposites and the intercalation mechanism of the technology were discussed. And then the interaction of OMT and the flame retardants were studied by UL94 test based on the flame retarded PBT. And then PBT and ABS alloys/OMT nanocomposites using terpolymers of random ethylene, methyl acrylate, and glycidyl...