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Mangya asbestos mine in Qinghai chrysotile , for example , the study of chrysotile etching mechanism and etching product performance , the purpose is to reduce the toxicity, and widen the chrysotile security applications , and demonstrated the feasibility of the nitrile rubber reinforcing agent . Achieved the following understanding : 1 using IR , XRD, SEM , DTA and TGA and nitrogen adsorption test methods of the Qinghai Mangnai chrysotile components , structure , surface features characterized . Come : the Qinghai Mangnai chrysotile crystal chemical formula (Mg5.62Al0.16Fe2 0.31Ni0.032) 6.122 [Si3.89O10] (OH) 8.62; oblique chrysotile , and contains a small amount of magnesite ordinary adsorbed water , piped water and hydroxyl water impurities ; containing chrysotile ; similar to the nitrogen adsorption isotherms of nitrogen adsorption isotherms with multi - walled carbon nanotubes , a type IV isotherm characteristics , corresponding to the hole (2 ~ 50nm ) structure, a specific surface area of ??134.7m2 / g. 2 the first time the Qinghai Mangnai etching chrysotile mechanism discussed by orthogonal experiment method derived synthetic nano-fibrous silica optimal experimental conditions for the concentration of hydrochloric acid 2 mol / L , solid liquid ratio 1:25 g / ml or so, the reaction time of about 120min . The etch rate of 55% under this condition . Etch product of chrysotile etch rate of 55% , SiO2 content of 90.5% for the nano- fibrous silica . By the IR analysis, the nano-fibrous silica containing deformation vibration of Si-OH peak at 950cm-1 and therefore have a reinforcing effect . The first time made ??a preliminary study of nano-fibrous silica reinforced nitrile rubber (NBR) composites , compared with the same process and formulations under reinforcement effect of precipitated silica was nano-fibrous silica has high elongation at break ( 432.85% ) , this composite has broad application prospects in the area of tire products , but overall , the use of the experimental process and formula reinforcing effect is somewhat less than the precipitated silica , to identify possible reasons : ① coupling agent overdose because the plasticizing effect of excess coupling agent may cause the physical properties of the composite declined ; ② contain impact modification effect of the coupling agent and reinforcing the role of free water .
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