Anticorrosion coating of the green revolution in the works

Since the early 1990 s, has carried on the "green revolution" of developed countries in the world, promote the development of coating industry to stride ahead toward the direction of "green" coatings. According to expert introduction, "green" heavy-duty coating industry in recent 10 years, the main varieties include solvent-free coatings, powder coatings and water-borne coatings, specific and can be divided into high solid coatings or solvent-free coatings, thermosetting heavy anticorrosive epoxy powder coating, waterborne epoxy coatings. For high solid coatings or solvent-free coating. According to expert introduction, with the deepening of human on environmental importance, even 100% high solid solid coating arises at the historic moment. Common anticorrosive coatings were found in around 40% can be volatile, the vast majority of them will be organic solvent, in the coating after construction to evaporate into the atmosphere, polluting the environment. Therefore improve the coating of solid content, reduce its volatile, application of coatings and its industrial development has very important significance. Overseas has developed solid content up to 95% of the anti-corrosion coating, the coating performance, has been applied to oilfield and the hydropower industry, and achieved good results.

 Thermosetting heavy-duty epoxy powder coating is also called the fusion bonded epoxy powder, the development in the fifties and sixties of the last century, realize the industrial production, more than 30 years after continuous developing, the technology has been mature, so far has more than 105 km pipeline to use the fusion bonded epoxy powder. According to expert introduction, fusion bonded epoxy powder technology starts late in China, in the 1980 s began to introduce and absorb foreign advanced epoxy powder and process and equipment. According to forecast the proportion of powder coating from a global perspective, now accounts for about 10% of the industrial coating; And the powder coating of Western Europe is the most mature, has accounted for more than 15%. The market for slightly bigger than the request. Production growth will remain at around 8%, but gradually digest the previous two years developing too fast.

 Waterborne epoxy coatings, using epoxy resin emulsion as epoxy group components, water soluble amine as curing agent, made into a two-component water-borne epoxy anticorrosive paint, apply to very strict with solvent is sending out of underwater steel structure, and in such aspects as construction sex of hardness, corrosion resistance, has with the solvent epoxy coating performance, effectively reduces the VOC content, is the development direction of anticorrosive coatings. Typical oil-in-water type epoxy anticorrosive coatings with styrene, acrylic acid and its esters monomers, epoxy resin as modifier, using a mixture of nonionic and anionic surfactant emulsifier, potassium persulfate as initiator on the emulsion polymerization, epoxy resin, acrylic resin emulsion.

  Water dispersible anticorrosive coating is the biggest characteristic is to mainly xylene solvent instead of ordinary coatings, gasoline and other solvents, not only reduces the cost, and reduced the pollution of the environment, and fire prevention, and easy to transport, storage and therefore has a broad application prospect. According to expert introduction, Beijing research institute of nonferrous metals da-wei cui et al. Experimental results show that the hydrophilic group on the resin at room temperature to form organic salt and organic salt agent, resin have good solubility in water; And under the condition of high temperature baking, into salt agent can fast volatilization, and resin on certain group and hydrophilic group, made into a film cured resin almost do not contain hydrophilic group, the other additives, under the joint action of the final film presents a hydrophobic.

  According to this principle, developed high temperature resistant waterborne anticorrosion coating of alkaline water corrosion. Heavy-duty coating is along the high performance, high efficiency, low energy consumption and low pollution direction. Good high corrosion resistance resin and the development of the new pigment and filler is the key to the development of heavy-duty coating; Development of long-acting type of green environmental protection coating is the coating in the direction of development, mechanism of environmental factors research, developing new coating materials and coating of environmental impact assessment database, contribute to achieving this goal.