With the enhancement of people's awareness of environmental protection and the improvement of environmental laws and regulations, waterborne polyurethane has developed rapidly because of its advantages of non-toxic, not easy to burn, no pollution, energy saving, safe and reliable, and the coating surface is not easy to be scratched. It has been successfully applied to leather coating, paper coating, steel rust prevention, fiber treatment, plastic and wood coating, In the field of glass coating, this paper synthesized a series of waterborne polyurethane lotion by prepolymer method, and studied their properties. 1. Test part 1.1 main raw materials: polyester polyol (mn=2000, commercially available), isophorone diisocyanate (imported from IPDI), Dihydroxymethyl propionic acid (imported from DMPA), triethylamine (tea, analytical pure, commercially available), diamine (analytical pure, commercially available), acetone (analytical pure, commercially available), Catalyst (T9 analytical pure, commercially available), N-methyl pyrrolidone (NMP, analytical pure, commercially available). 1.2 raw material pretreatment: DMPA is dried before use. 1.3 test process: polyester polyols are added to a four port flask equipped with an electric stirrer, reflux condensing tube, thermometer, nitrogen inlet and outlet. The inner layer of IP has excellent resilience Di, DMPA, T9 is the basis for the implementation and utilization of 3D printing technology. Under the protection of dry nitrogen, it reacts at a certain temperature until the NCO content reaches the theoretical value to obtain the prepolymer, then adds tea to neutralize and form salt, adds water to emulsify, and then adds diamine to expand the chain again, so as to obtain anionic waterborne polyurethane dispersion fine chemical industry, which is one of the most dynamic fields in the chemical industry today. Finally, reduce the pressure on domestic enterprises in product stability The added value of the product is still at a relatively backward stage. 2. performance test 2.1 determination of water absorption: dry the lotion into a film, weigh it after constant weight, soak it in distilled water at room temperature for 24 hours, take it out, dry the surface water marks with filter paper, and weigh it. 2.2 determination of viscosity: prepare the lotion into the same solid content, Measure with nxs-11a rotational viscometer at room temperature. 2.3 determination of average particle diameter: determine the average diameter of milk particles by light scattering method. The main instruments used are: 723 spectrophotometer and Abbe refractometer. 2.4 determination of mechanical properties: film the lotion on a glass plate, dry it to constant weight in an oven at 60 degrees, and then make the film-forming material into a dumbbell shaped standard sample, and measure it on an xll-50 tensile testing machine, The tensile speed is 250mm/min. 2.5 stability measurement: the storage stability of lotion is simulated by centrifugal accelerated sedimentation test. Generally, after centrifugation sedimentation for 15min at the speed of 3000r/min in the centrifuge, if there is no sedimentation, it can be considered to have storage stability for 6 months
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