Synthesis Of PVAC Fof Preventing Coal Spontaneous Combustion And Study On Behaviors

The output and consumption of coal in China is premier in the world, and it occupiesabout 75 percent of the internal primary energy output and total consumption. However, thecoal spontaneous combustion is very serious in our country. It seriously restricts the high-yieldand high-priced coal mines' safe production and development. And also it caused considerablenatural resources waste, environmental pollution, personnel and property loss. Thus it can beseen that it is a very important assignment of studying the technology of preventing and curingthe coal mine spontaneous combustion. Furthermore, it is a new field for studying thetechnology of preventing and curing the spontaneous combustion of coal through chemicalmethod. Therefore a new technology of preventing and curing coal spontaneous combustion israised in the thesis.The theory of the thesis is studied according to the theory of reaction of coal and oxygen.A new polymeric emulsion having good membrane-forming behavior and cohesive action issynthesized. It is used on the coal mine by spray and inject, and it forms a film of membranehaving good toughness to block the oxygen. The membrane can block the contact of coal andoxygen, slower the reaction rate of coal and oxygen. So it can prevent the coal spontaneouscombustion; moreover, it also can be act as explosion-protection and dust suppression.The polymeric emulsion is synthesized mostly by vinyl acetate, and compound with fewsecond-monomer and third-monomer to rectify. It reacted on the condition of water being thereaction medium, and through free radical polymerization. The polymeric emulsion has goodpenetrability and membrane-forming behavior, and then mixed witli phosphonic hydroxylspecies inflaming retarding agent. The methodology process of the synthesis is simple.In the thesis, I make choice the best synthetic process according to the orthogonalexperiment design at first, and then test the behaviors of the polymeric membrane made of thepolymeric emulsion of the best synthetic process, such as the air permeability (that is thebehavior of obstruct oxygen) of the membrane, electric mirror analysis of the membrane, IRspectrum analysis of the membrane, and so on.Through the test of the behaviors and lots of experiments, it can be seen that thepolymeric emulsion made of the best process has a lot of advantages, such as membrane-form time is short, the viscosity is well situated. And the membrane has a lot of advantages too, forexample, the waterproof is better, the toughness is better, the behavior of obstruct oxygen isbetter, and it can meet the requirement of construction in the coal mine. What I researchedestablish a stable base for the construction in the coal mine next.