Synthesis And Application Of Graft Copolymer Of Oxidized Starch With Acrylic Acid An Acrylamide

The dust pollution affects many aspects of human environment, such as toxicological and sensory effects on humans, agricultural crops, grass, livestock, reduction of visibility, and abrasion and corrosion of materials. In most cases, controlling dust pollution is often very difficult and expensive. Therefore, the dust prevention and control technologies have been investigated and applied for many centuries. One of the dust control methods is the invention and application of the chemical dust suppressants, with the speedy development of chemical industry and new chemicals.Polymer material is a kind of new chemical 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. This research area has significant future and has been widely used in many fields. The new dust suppressant material which has been researched in this thesis is graft copolymer of starch with acrylic acid and acrylamide which has a good water-solubility.The dust suppressant is prepared in three stage procedure, including the preparation of oxidized starch, the gelatinization of oxidized starch and graftcopolymerization. The synthetic method and reaction conditions were discussed in the thesis. The results showed that: with 60% quality of AA, 0.4% quality of initiator, 50% of neutralization at the temperature of 50℃heating for 6h ,the viscosity of the product is 212.6mPa·s, the product has good sand fixation performance for practical application.The physical and chemical characters of the dust suppressant was also analyzed, including: the viscosity test on the different component, different solid content, different temperatures of 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 dust suppressant and had suitable viscosity and good thermal stability between the room temperature and 100℃.According to the practical application of the dust suppressant, 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 dust suppressant 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 dust suppressant with more than 3.0% solid content, the sand shell is able to bear the surface temperature of 70℃; spraying dust suppressant 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 1.24MPa, and the compressive strength will increase along with the adding of solid content. The results proved that the polymer has good properties of dust suppression.From the physical and chemical characteristics analytical results and the applied properties tested results of the dust suppressant, we can see that it is a kind of multifunction sand-fixation material and be able to meet environmentally friendly demand, and have a wild applied prospect.