| Microemulsion having transparent or half transparent appearance is athermodynamicly stable and isotropic dispersed system that is composed of twokinds of solution which are not soluble to each other, it doesn't kick out whencentrifugalized. Since microemulsion is firstly reported by Schulman in 1943, itstheory and application in practice have been developed quickly.Its factualapplication began in the 1930s and were used in many fields of industry andtechnology. Especially since the 1990s, the research about the application ofmicroemulsion has been developed more quickly, some monographs andsynthetical articles summarized the theory and applied fruits of emulsion.Chinabegan research microemulsion since the 1980s and has have a good harvest in itstheory and application.The value of the application of microemulsion can't beneglected and its research has deep significance.Ultrafine particles are widely used in many fields in life and production.Generally the method of the preparation of ultrafine particles are divided intotwo sorts: physical and chemical. The chemical method of microemulsion is amethod which is less researched but perfect. In microemulsion, small waterpoolis surrounded by single surfactant and accessorial surfactant molecular layer, itsdimension is about several or tens of nano-meters.These water-pools areseparated by each other and they are the reaction vessel.It has bigger interfacewhich is in favor of chemical reaction, so it's another useful technology ofpreparing ultrafine materials. Compared with other chemical methods, theparticles prepared with microemulsion do not tend to reunite and they are easilycontrolled and dispersed well.First, the article mainly researches the application of reversedmicroemulsion in the preparation of ultrafine particles and then tells the basicprinciples. If we want to prepare ultrafine particles using the method of reversedmicroemulsion, the first step is to prepare reversed emulsion. It issome difficultduring the preparation of microemulsion due to the complication of its phaseconversion. Thereare many factors influencing the phase balance ofmicroemulsion, includingproportionofwater vs oil, temperature, sort ofsurface-modifying agent, sort of solvent and so on, which is deeply discussed inthe article. These factors also influence the diameter of particles. This articlemainly discusses three sides: how the value of R and the content of accessorialsurfactant influence the diameter of ultrafine SiO2 particles, the comparation oftwo infrared spectra got with two different solvents. The baking temperature isespecially meaningful in the preparation of ultrafine particles and here get therules how the baking temperature and time influence the diametere of particles,for example the primary production of microemulsion must be roasted invacuum and then in muffle furnace. The article summarizes the rule of how timeand temperature influence the diameter of SiO2 particles, compare the XRDspectrum of ZnO particles prepared with the method of reversed microemulsionand ZnO particles prepared with the method of homogeneous precipitation. Thesuperiority the method of reversed microemulsion is proved by thiscomparation.The purpose of researching these factors is to find better way ofcontrolling diameter and dispersion of particles.If the ultrafine particles want to be added into polymer or emulsion, theirsurface must be modified due to their high surface energy. The article has aprimary research about the surface modifying of ZnO, firstly tells the principleand then discusses how some factors including modifying temperature,modifying-agent, modifying time, PH value and so on influence the effect ofmodifying, compares the distribution and SEM photos of modified particles andunmodified particles. This is meaningful in particle surface modifying.Paints containing fluorine play a key role today. In all kinds of paint, paintscontaining fluorine has a lot of predominant performance, such as weatherability,heat resisting, low temperature resistance, chemical-resisting due to the bond ofC-F having high electronegativation. Its nuclear technology was produced inDopond Company. After several-tens of years developed, paints containingfluorine were widely used in chemical industry, electric industry, mechanicalindustry, navigation industry, family commodity and so on and became the mostimportant kind of paints after crylic acid paint, polyurethane paint, organosiliconpaint. At present, there are 8 sorts of paints containing fluorine researchedmostly: water-borne, low content of organic solvent, thermoplastic powder,degradation of poison, fireproofing and burning resistance, electric and heating,nite, abrasion resistance.The preparation of emulsion containing fluorine is most important part inthe production of water-borne paint. It is known that core-shell structure andemulsion containing fluorine are both helpful to improve the performance ofemulsion and its film, the combination of these two sides will become moremeaningful in advancing the performances of emulsion, which is mainlyresearched in the article. Modifying agent is a key factor, which has greatinfluence on monomer conversion, and the performance of emulsion and film,especially on the strucrure of core-shell and the article compare the SEM photoshaving different content of emufying agent. Also there are many other factorsinfluencing the structure of core-shell, such as reactor, reacting time,polymeration arts and crafts, and so on, which is detailedly discussed in theparticle. Here the gives the relationship between reactor and coagulurn ratio,TEM photo of 4h, and the importance of advanced emufying. Fluorine nonomerhas low activity and the C-F bond is very solid, so the reacting system which hasFluorine monomer is essentially different compared with reacting stystemhaving no Fluorine monomer. The measurance of the quality offluorine-containing core-shell emulsion of polystyrene-acrylate proves that ithas better stability, opticalclarity,resistance toatmosphere,hardness,wash-resistance and so on compared with common emulsion and commoncore-shell emulsion.
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