Controllable Preparation Method And Polymerization Process Of Latex In Ultra High Environment

The main method to produce latex particles in the process of emulsion polymerization is bead nucleation whose precondition is the diameter of monomer droplet must reach a certain range.Thus,in the industrial preparation of emulsion polymerization,there are defects of limited yield and high energy consumption.How to achieve high pass emulsion controlled preparation is one of the important directions in current research.As a widely used process intensification technology,high gravity technology can make the fluid highly dispersed in a short period of time,update the fluid interface rapidly,and make the droplet unit collide violently,so as to prepare a large number of micro droplets.To achieve this,it depends on the high-gravity made by rapid rotation of rotor and the shear action of fillers.Due to its small amplification effect and high comprehensive efficiency in the production process,it has been widely used in the preparation of nano material,the treatment of pollutant gas,the enhancement of multi-phase complex reaction process and so on.Based on the key problems in the process of controlled emulsion polymerization,such as controllable preparation of macroemulsion and new technology of polymerization,in the topic.I propose a controllable preparation process based on ultra-high speed rotating packed bed to enhance the dispersion of droplets and emulsions,and combine the emulsion polymerization system with the new process to develop the research ideas for achieving controllable polymerization process.The main innovations are as follows:1.Using water as the main medium,the feasibility of micro droplet preparation in Ultra High-Speed Rotaing Packed Bed(UHS-RPB)was analyzed by laser diffraction technology.The effects of high gravity level,initial velocity of liquid phase feeding,fluid viscosity,fluid surface tension,packing type and pore size on the average diameter and diameter distribution of micro droplets were explored.The results showed that the average diameter of the droplet decreased with the increase of rotation speed,viscosity and pore diameter of the filler rose up with the increase of surface tension,and slightly went up with the increase of initial velocity of the liquid.The dimensionality analysis method was used to correlate the average droplet diameter under different conditions,and the error between the predicted value and the experimental value was within 15%.In the range of 1000-9000 r/min,the average diameter of the generated droplet was 27-182?m,and the droplet size could be controlled by adjusting the rotation speed and the pore size of the filler.The droplet diameter distribution was in line with the R-R distribution model.Compared with the rotating cup and disk,the average diameter of droplets prepared in this study was smaller at the same rotating speed.2.Filler was an important factor affecting the diameter and distribution of micro droplets.This topic compared the performance of different packings in the preparation of micro droplets in the preparation of micro droplets in high gravity environment.The performance of foam nickel filler and 3D printing screen filler was compared emphatically,and the better filler for UHS-RPB microdroplet was determined.The effects of initial velocity and physical parameters such as liquid viscosity and surface tension on the average diameter and diameter distribution of micro droplets were studied.3.A new method based on UHS-RPB is created.In this method,kerosene or water was used as emulsifying system.The emulsifying properties of UHS-RPB were studied comprehensively.The effects of different water or oil flow rate,speed,filler type,filler pore size and emulsifier content on the average diameter and diameter distribution of dispersed phase were studied.Result showed that increasing the rotor speed and reducing the pore diameter of the packing can improve the emulsifying performance of the reactor,reduce the average diameter and width of the emulsion dispersed phase,reduce the oil flow rate and increase the amount of emulsifier,and the average particle size of the emulsion will also decrease.In the range of 4000-9000 r/min,the average diameter of the dispersed phase of the emulsion is 13-48 ?m.Compared with traditional high speed stirring,it can reduce the work of continuous phase.4.Styrene maleic anhydride(St-MAH)alternating copolymerization system was used in this study to prepare styrene maleic anhydride copolymer microspheres by emulsion polymerization.Due to the hydrolysis of maleic anhydride,the former mainly prepared microspheres with different morphologies by precipitation polymerization,especially self stable precipitation polymerization.In this project,the average particle size(D32),particle size distribution width and electron microscopy(SEM)were used to analyze the morphology of copolymer,and the structure of polymer was analyzed by FT-IR.Firstly,the polymerization reaction time,stirring speed,monomer ratio,emulsifier and crosslinking agent were explored under the condition of high-speed mixer emulsification The influence of the ratio and the proportion of initiator on the particle size distribution and morphology of polymer products was studied.The results showed that the monomer conversion rate remained stable after 120 min.When the ratio of maleic anhydride was 40.0:57.5,the emulsion polymer product with the same morphology and uniform particle size was obtained.The influence of operating parameters,formulation system and polymerization process on the morphology,particle size and particle size distribution of StMAH copolymer microspheres were defined.5.Based on UHS-RPB technology,the preparation of emulsion in St-MAH emulsion polymerization was achieved,which broke through the traditional preparation method and successfully prepared St-MAH copolymer microspheres with special morphology and special properties.Compared with traditional emulsion polymerization,on account of UHS-RPB emulsion polymerization process is easy to achieve,providing a new method for emulsion polymerization.