Synthesis And Research Of Sand Fixing And Dust Suppressant P(VAc-BA)

Land desertification is becoming a worldwide environmental problem in recent years, which greatly restricts the sustainable development of the economy of our country. The execution of chemical sand-fixation is an effective approach to restrain desertification process, which has great practical significance on economic development and ecological environmental protection. Synthetic polymer material is a kind of new chemical sand-fixation and dust suppressant material, It can form lamella on the sand dunes or sandy surface which can prevent the wind erosion but also maintain and improve the nature of the sand in order to control and improve the environment, increase the productivity of the sandlot. This research area has significant future and has been widely used in many fields. The new sand-fixation material which has been researched in this thesis is poly vinyl acetate-butyl acrylate emulsion which has a good water-solubility.The sand-fixation and dust suppressant is prepared in three stage procedure, including emulsification, seed monomer polymerization and the remaining monomer polymerization. The synthetic method and reaction conditions were discussed in the thesis, the influence of the proportion of monomer, the amount of protective colloid, the amount of initiator, the amount of emulsifier and the emulsifier ratio on emulsion properties were discussed. The results showed that: with 30% quality of BA, 0.8% quality of initiator, 3% quality of protective colloid, 4% mass content of total emulsifier in the 1:3 ratio, the viscosity of the product is 155.40mPa·s, the product has good sand fixation performance for practical application.The physical and chemical characters of the sand-fixation and dust suppression agent was also analyzed, including: the viscosity test on the different component, different solid content, different temperatures of sand-fixation and dust suppressant, FTIR analysis, TG test and SEM analysis. FTIR analysis was used to test the characteristic group of the products; TG test was used to test the thermal stability of the products; SEM was used to observe the shape characteristic of the sand shell. The results showed that the sample was a good sand-fixation agent and had suitable viscosity and good thermal stability between 0-220℃.According to the practical application of the sand-fixation and dust suppression agent, taking the sand soil as research object, water retention, water resistance, the tolerance of high temperature, wind corrosion resistance and compressive strength were studied. The results showed that: the sand-fixation and dust suppression agent has a certain water retention when the solid content is more than 3%; spraying sand-fixation with 2.0-6.0% solid content in 1L/m~2 dosage, the sand shell has a good water resistance; spraying sand-fixation with more than 2.0% solid content, the sand shell is able to bear the surface temperature of 70℃; spraying sand-fixation with more than 6.0% solid content, the sand model loss less than 0.1% quality, has a good wind corrosion resistance; the compressive strength of the sand model is up to 0.87MPa, and the compressive strength will increase along with the add of solid content. The results proved that the emulsion has good properties of sand-fixation and dust suppression.From the physical and chemical characteristics analytical results and the applied properties tested results of the sand-fixation and dust suppressant, we can see that it is a kind of multifunction sand-fixation material and be able to meet sand-fixation demand, and have a wild applied prospect.