Synthesis And Application Of Benzoic Acid-Bentonite

Recently,the polymer/inorganic composite nano-materials are highlighted due to the manufacturability from organic part,as well as functionality and structural properties out of inorganic material.Bentonite,a species of natural clay mineral with nano-scaled layered structure,is widely applied in preparation of polymer/bentonite as inorganic dispersion phase. It is essential to modify bentonite to ensure evenly dispersion of nano-scaled bentonite in the matrix of polymer.In this paper,exfoliated benzoic acid organic bentonite was prepared with alkaline Ca-bentonite and benzoic acid;the former is used for the exchangeability and the latter is an organic modifying agent.According to single factor analysis,the optimum preparation conditions were obtained with respect to the organic content of benzoic acid:5.00g alkaline Ca-bentonite dispersed in 50mL haxmethylene alkyl;4.50g benzoic acid dissolved in 60mL mixed solvent of haxmethylene alkyl and alcohol;then reaction under circumfluence over 3hrs.The organic content of exfoliated benzoic acid clay product is 40.3%.The experimental characterizations indicate that:during the process of alkaline Ca- organic modification, bentonite is exfoliated into nano-rods with the destruction of layered structure and exfoliation of bentonite.Additionally,with this benzoic acid organic bentonite,the polystyrene/bentonite nano-composite was prepared using emulsion polymerization method.Experiments were performed to examine the effects imposed by conditions for dispersion,such as dry, neutralization,and addition of methanol,upon dispersion of benzoic acid clay in the styrene monomer.Finally,the optimum dispersion condition was achieved through these experiments. Moreover,two optimal processes were regressed through uniformLy designed experiments. One processes aiming at preparation of high-viscosity polystyrene composite is:10mL potassium persulfate as initiator,30mL emultant sodium lauryl sulphate,polymerization temperature 75℃,polymerizing lh,addition of 3%bentonite.The molecular weights of product which made by this way is 683000.The other process aiming at maximum yield, which equal 95.1%,is:22mL initiator,polymerizing 3hrs at temperature of 95℃,addition of 5%bentonite.Experimental characterizations of polystyrene/bentonite composite indicate that: benzoic acid bentonite is evenly dispersed into polystyrene with the dispersion of 50nm;and the thermal decomposition temperature as well as tensile property of the composite material are remarkably improved.