Study On The Preparation Of Special Structural Nanomaterials Containing Antimony, Magnesium Compound And Their Flame Retardant Property

This work is composed of three parts: one is the preparation of the nanoparticles containing antimony (Sb), with star-like, belt-like, and hollow structure, by modified soft template method in solution. The method adopted in the preparation was seldom present in the literature, which would be instructive in the preparation of other nanoparticles; Second is the preparation of surface-modified Mg(OH)2 nanoparticles by azeotropic distillation technique, which might be a novel route to produce surface modified nanoparticles. Third is the magnification of synthesis application as polymer additives, and the test of their properties. Based on the above results, the following main conclusions are reached:1 On the basis of the polymer coil structures in the medium, the certain sized PEG coil microspheres were fabricated in water-ethanol by controlling the process order; then, the primary nanoparticles of Sb2O3 precursor were bond with them by hydrogen bond to form a"core-shell"structure with coils microsphere as core and Sb2O3 precursor as shell; finally, the hollow Sb2O3 microspheres were obtained by drying. The whole forming process was basically tailed by transmission electron microscopy, and the possible forming mechanism was put forwarded.2 Due to the agglomeration tendency of Sb2O3 precursor, the Sb2O3 precursor was dispersed into the aqueous solution containing surfactant by low-power ultrasonic, and, then tune agglomeration and growth of Sb2O3 precursors, with the weak bonding of surfactant to precursors, to prepare the series of special structure Sb2O3 nanoparticles, such as star-like and belt-like and so on. The corresponding forming mechanism was also brought forward.3 Under the condition of mechanical stirring, the Sb2O3 belt-bundle nanoparticles were also successfully prepared by dipping the antimony salt ethanol solution into the surfactant aqueous solution. The optimized technical condition was obtained through many experiments in lab, which was adopted to produce sample in 50 L reactor. When the obatined belt-bundle morphology sample was added into flexible polyvinyl chloride (PVC), the flame retardnt property was weakly better than those of composites filled with commercial grade Sb2O3 due to the same flame retardant mechanism; and for their bigger contact area and better abhension in matrix, the mechanical property was better than those of composites filled with commercial grade Sb2O3.4 When the surface-modified agent was introduced into the conventional azeotropic distillation system, the dry and surface-modification of Mg(OH)2 nanocrystallines is realized in one pot, and the forming mechanism is also discussed. In comparison with commercial grade Mg(OH)2, for one thing, when the surface-modified Mg(OH)2 nanocrystallines were introduced into acrylonitrile-butadiene-styrene copolymer(ABS), the flame retardant property wasn't obviously improved because the lamellar Mg(OH)2 was existed as spheric agglomeration in the matrix and the flammable gas isolated layer wasn't formed. For another,the better mechanical properties was obtained for bigger contact area of nano-Mg(OH)2 and their better abhension in matrix.This method would be useful in the preparation of other oxide nanoparticles with special structure or surface- modification.