| Rapid development of architecture industry and issuing of environment laws make architecture waterborne coatings a good development foreground. Although there are various kinds of exterior wall waterborne coatings in the market, low-class products exceed purchasing needs and high-quality products are short of supply, so developing high-quality and high-performances, low-price emulsions and corresponding coatings are urgent. At present, researches of acrylate emulsions, alkoxy silane modified acrylate emulsions and corresponding coatings have made more progress, but researches of fluoro-containing emulsions and corresponding coatings just are in the stage of initial step. Fluoro-containing coatings are of high weather resistance, scrub resistance, chemical solvent resistance and stain resistance, etc., which meet some special requirements of many fields. Combining fluoro-resin and acrylate resin will combine their merits and improve their performances. To prepare novel materials with excellent performances of both resins is of great significance.Several methods to prepare fluoro-containing emulsions have been reported, but because of some reasons they are difficult to utilize in domestic market. Our research group used different way, avoiding fluoro-olefin polymerization, to modify commercial product polytetrafluoroethylene-PTFE dispersive emulsions, and got composite modified emulsions with the performances between binder and filler. It means PTFE was looked upon as a filler and was treated to be a binder, i.e, acrylates were used to modify PTFE and the emulsions with performance of binder were gotten. The preparation process of the experiment was simpler and low cost. The performance of the modified emulsion made great promotion, especially on weather resistance and stain resistance. It could form film ambient. It was a novel and effective method to prepare fluoro-containing emulsions.Research works included the following contents:The acrylate emulsions were made of a fluoro-containing emulsifier and non-ionic surfactant OP-10. The self-made acrylate emulsions were of better stability and better performance and looks bright and plump. The principles to select materials and experiment conditions to prepare acrylate emulsions and PTFE/acrylate composite modified emulsions were inspected details. By the emulsion polymerization experiments, two kinds of modified composite emulsions were prepared.The emulsions were characterized and tested. Five independent ways but supplement each other were designed to prove the idea of experimental design. They included FTIR, TEM, granularity distributing, small seed polymerization and rheological change. All results indicated experiment-planning idea was doable. The structure of latex particles and composite modified mechanism both in macroscopic view and microscopic view were explored.The different properties of the products were tested. The influence of initial seed quantity, monomers quantities and their ratio, emulsifiers' quantities, initiator quantity, experiment temperature etc on the emulsion performances was explored. The factors influencing polymerization stability were investigated. Finally, emulsifier quantity was determined to be 1.8%~1.9% and initial seed percentage was 14%~18%. Solid containing of composite modified emulsion was 40%-50%. The percentage of functional monomer was controlled below 3%. When prepared the second stage seed, normal swelling method was adopted. Stirring speed was controlled 120~250rpm and should be kept stable. APS was initiator and the ratio to total monomers quantity was 0.45 %~0.61 %.Rheological properties of emulsion products would influent that of coating products, so...
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