| Tourmaline, one kind of unique spontaneous electropolar mineral, has the function of emitting far infrared rays and releasing anoin. Therefore it is widely applied in many fields such as environmental protection, functionality textile and building materials etc. Though ultrafine powder of tourmaline has special effects, its application performance is serious influenced by reuniting mutually. So it is important that enhances ultrafine powder of tourmaline's dispersivity. This article utilizes the chemistry analysis, EMPA, ICP, XRD, FTIR, DTA,TG analysis methods to carry on the test to mineralogy characteristic of tourmaline from Xinjiang Altay mica second mine, and has conducted the research to ultrafine powder of tourmaline's preparation craft. It has summaried ultrafine powder of tourmaline mechanochemical effects. Finally based on colloidal dispersion stabilization theory, by using sedimentation time, sedimentation volume, medium particle distribution, Zeta electric potential determination etc, it had investigated by employing sodium polyacyrlate, potassium polyacrylate (polymer surfactants), sodium polyphosphate, sodium hexametaphophate (inorganic), sodium dodecyl benzene sulfonate (organic) which carries on the superficial modification to ultrafine powder of tourmaline. Finally it has determined the best modified technological conditions. Using FTIR, DTA, TC and SEM, it has established ultrafine tourmaline's stabilization mechanism andsurface adsorption model, and proposes water-soluble superficial modifier and tourmaline action mechanism. The contents of this dissertation are as follows:Xinjiang Altay mica second mine tourmaline sample's is the magnesium tournaline. Through using grinding medium reasonably and optimization technological conditions, has gotten regular morphology ultrafine tourmaline which distributes narrowly. After grinding 60 min the particle size increases achieves the limit, and the minimum particle size is 0.619μm. The maximum specific surface area reaches 33.47 m2/g. Using MATLAB program to conduct ultrafine grinding curve fitting research to the tourmaline, has established its mathematical model.After superfine, mechanochemical effects research indicated: the crystal lattice has the inflation in the process of lapping, but it is the lattice distortion category. The ultrafine grinding causes tourmaline some vibration fine structure vanishing and the peak to present the characteristic which degenerate and wide, the band which [SiO4] causes vanishes gradually and red shift. In the superfine process, the mechanical energy transforms to internal energy of tourmaline, which causes heat absorption effect maximum value temperature to have reduces (1004℃reduces by the original 907℃, reduces the scope to reach 97℃). Indicated to the smallest particle size tourmaline magnetism nature's research, tourmaline coercive force increases. The ultrafine grinding causes the crystal lattice periodic destruction, enhances the crystal lattice polarity vibration non-simple harmonics effect, and improves the tourmaline in certain wavelength range infrared emissivity effectively. The anoin test result indicated: Ultrafine powder of tourmaline produces the anoin increases to a certain extent. When the particle size slightly increases to certain extent, the anoin amount reduces.The ultrafine powder of tourmaline superficial modification processing best modified formula and the technological conditions are: At temperature 83℃, pH is 11 conditions, compound modifier (sodium polyacyrlate gathered with sodium polyphosphate), the best amount used is 1.8% (sodium polyacyrlate 1.2%, gather sodium polyphosphate 0.6%).The modified assistant is silica, the best amount used is 4.0%. Dispersing agent member dissociation balanced related with pH value, also the dispersing agent member's dissociation balanced immediate influenced dispersing agent member's charged situation and the solution extension condition. Finally, affects the powder body's electrostaticstatic steric function. Results show that water dispersion system stability which has 10wt% tourmaline intensely is influenced by dispersing agent amount and pH value.The test result indicated: compound modifier has bonding with tourmaline surface hydroxyl. Carboxyl in sodium polyacyrlate (-COOH) has had dehydrated esterification response with ultrafine tourmaline pellet surface hydroxyl (-OH). But silica basically does not change the tourmaline itself nature. Zeta electric potential's absolute value also enhances from 9.5mv to 28.6mv, therefore greatly enhanced electrostatic repulsion function between tourmaline.According to analysising the modification mechanism, it has gotten the adsorption model of tourmaline. Modifier acts on tourmaline surface respectively by chemical adsorption and physisorption. Silica fills between tourmaline. When the sample disperses in the water, the modifier endows with ultrafine tourmaline surface high Zeta electric potential and increases the electrostatic repulsion function between the ultrafine tourmaline. In addition, it will also form steric stabilization or vacancy stabilization in the ultrafine tourmaline surface. Thus improve the stability of the powder dispersion in the water. Silica adsorption on the the ultrafine tourmaline surface, may reduce the fluid bridge strength between the granule.Thus the granule spacing increases, reducing mutual caking and enhancing dispersion. The modification mechanism is: The modified tourmaline's surface forms three kind of adsorbed layers. The inner layer is chemistry adsorbed layer, which modifier has reaction with tourmaline surface hydroxyl. The outer layer is the modifier assistant.This research is subsidized project by NNSF"The compound particle's the polar mineral tourmaline with the semiconductor oxide (ZnO and so on) environment action mechanism research"and Ministry of Education institutions of universities for doctor subject the special scientific research foundation"The environment material tourmaline powder membrae tectoria strengthens the mechanism research".
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