Effect Of Acylated Phospholipid Emulsifier On Properties Of Field Mixed Emulsion Explosive

Emulsifier,as one of the important components in on-site mixed emulsion explosives,is mainly used to mix immiscible liquids such as water and oil into a uniform emulsion,thereby improving the energy density and explosive power of on-site mixed emulsion explosives.In addition,emulsifiers can also reduce the thermal sensitivity of on-site mixed emulsion explosives,improve their safety,and reduce the risks during explosive preparation and use.Therefore,it is of great significance to study a composite emulsifier suitable for on-site mixed loading of emulsion explosives.This article presents the preparation of acylated phospholipid composite emulsifiers by acetylating soybean phospholipids and compounding them with Span80.By adjusting the proportion of acylated phospholipids in the composite emulsifier and comparing the particle size,viscosity,crystallization amount,conductivity and other parameters of the matrix,the effect of acylated phospholipid content on stability was studied;By simulating the transportation oscillation process,observe the changes in particle size,microstructure,viscosity and other parameters of the sample before and after vibration,and study the effect of acylated phospholipid content on anti vibration properties;The thermal decomposition process of the sample was measured by Thermogravimetric analysis technology and C80 microcalorimeter,the activation energy was calculated by various algorithms,the reaction mechanism was analyzed,and the effect of acylated phospholipid content on thermal stability was studied;The impact of acylated phospholipid content on thermal sensitivity was studied through burst point testing,and the main conclusions are as follows:(1)After adding acylated phospholipids,the negative charge of acylated groups significantly increases the repulsive force between droplets,enhances the dispersion force,accelerates the rate of Austenitic ripening and polymerization within the system,and increases the interfacial tension.As the mass fraction of acylated phospholipids in the composite emulsifier increases,the viscosity of the on-site mixed emulsion explosive matrix increases,the rheological properties decrease,and the average particle size of the inner phase droplets sharply decreases,with a more concentrated distribution range,As the surface tension increases,the crystallization amount and conductivity also decrease.(2)The vibration effect will accelerate the rate of austenite ripening and polymerization collision of liquid droplets in the emulsion matrix.Compared to Span80,acylated phospholipids can effectively increase surface tension and introduce negative charge groups,increasing the repulsive force between droplets,hindering the mutual attraction and fusion of small droplets into large droplets,and inhibiting the increase of internal phase particle size.After acylation modification,the hydrophilicity of phospholipids is improved,making it easy to form a network like structure.Even after a long vibration period,the proportion of emulsified layers decreases relatively slowly,resulting in a relatively lower degree of matrix disorder.With the increase of acylated phospholipid emulsifier content,the vibration resistance stability of on-site mixed latex matrix gradually enhances.(3)As the mass fraction of acylated phospholipids in the emulsifier increases,the reaction initiation temperature To,DTG peak temperature Tp,and apparent activation energy E of the thermal decomposition process of the latex matrix gradually increase,and the thermal stability gradually enhances.Calculate decomposition rate using Kissinger method,Ozawa method,Starink method,Popescu method α At 20% to 95% of the kinetic parameters,the four results tend to be consistent.The most probable kinetic mechanism function of the emulsion explosive matrix was determined using the Coast Redfern method: the on-site mixed emulsion explosive sample emulsified separately by Span80 obeyed the Jander equation,belonging to a three-dimensional diffusion spherical symmetric model.The sample emulsified by acylated phospholipids composite obeyed the Z-L-T equation,belonging to a three-dimensional diffusion control model.The onsite mixed emulsion explosive matrix sample prepared with acylated phospholipid composite emulsifier has a different thermal decomposition kinetics equation from Span80 emulsification alone.(4)With the addition of acylated phospholipid composite emulsifier,the increase of dispersion force will expand the activation energy channel,improve the strength of interfacial facial mask,and the increase of hydrophilicity will also reduce the solubility of surfactant and increase the interfacial tension.In addition,phospholipid groups will introduce highly reactive unsaturated double bonds during the reaction process,forming an interfacial adsorption membrane.In the thermal decomposition process,the greater the strength of the interface facial mask,the better the thermal stability,and the greater the activation energy,the main body of the thermal Chemical decomposition shifts to the direction of high temperature,and the initial decomposition temperature is increased.Compared to Spa80,the heat resistance of emulsion explosive matrix has been greatly improved.(5)There are differences in the effects of acylated phospholipid content and sensitization ratio on the explosion point of on-site mixed emulsion explosives: for onsite mixed emulsion explosive samples with the same acylated phospholipid content,the explosion point decreases with the increase of sensitization ratio,and the activation energy increases with the increase of sensitization ratio;For on-site mixed emulsion explosive samples with the same sensitization ratio,the explosion point decreases with the increase of acylated phospholipid content,and the activation energy increases with the increase of acylated phospholipid content.Figure[31]Table[29] Reference[103]...