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The solvent-free polyurethane adhesives containing volatile organic compounds (VOC), resulting in the use of more and more restricted. Waterborne polyurethane adhesive dispersion medium is water, compared with the solvent-based adhesives, solvent-free volatile, non-toxic, odor, non-flammable, and does not pollute the environment, convenient operation, etc., so more and more people attention. However, waterborne polyurethane adhesive on the market, mostly carboxylic acid salt water-based polyurethane adhesive, the presence of solids low viscosity, crystalline defects and poor mechanical properties, modern footwear industry can not meet the high-performance environmental type adhesive request. This topic selection polyadipates butanediol ester diol (PBA), hexamethylene diisocyanate the ester (HDI), isophorone diisocyanate The ester (IPDI) as the main raw materials, 1, 4 - butanediol (BDO) for small molecule chain extender, the hydrophilic monomer, ethylenediamine, ethylenediamine yl ethanesulfonate after the chain extender, with acetone synthesized solids content of 50% of the sulfonate type polyurethane emulsion. Formulated using the emulsion waterborne polyurethane adhesive drying speed, good wettability of PVC leather, the initial and final high peel strength, to meet the the footwear field of environmentally friendly adhesive. Prepolymerized reaction temperature, the temperature of the chain extender of the hydrophilic monomer, the influence of the time of the chain extender, emulsified dispersion speed, ethylenediamine adding sequence of process parameters on the properties of emulsion and film performance, examines the amount of hydrophilic monomer polyol types of different hard and soft segment ratio formula factors affect the performance of the emulsion and film, to determine the optimal formulation and synthesis conditions. I.e. prepolymerization temperature of 70-75 ℃, the temperature of the chain extender of the hydrophilic monomer is 60-65 ° C, the chain extender time for 60-70min, emulsifying and dispersing speed of 6000rpm, to PBA2000 as soft segment, set a hydrophilic monomer content of 2.0-2.5% (mass percentage of the total solid), hard and soft segment ratio of 2.96, the best overall performance of synthetic polyurethane emulsion. Fourier transform infrared spectroscopy, differential scanning calorimetry, X-ray diffraction, dynamic mechanical thermal performance analyzer, scanning electron microscopy, the best formula and synthesis conditions emulsion into the film crystallization Performance. Analysis showed that although some of the hard segment of the aqueous polyurethane rigid groups exist, so that the force between the soft and hard segments enhanced part of the hard segment is mixed in to the crystallinity of the soft segment of the micro-regions, destruction of the orderly nature of the soft segment, affecting the crystalline soft segment, but these acts and can not hinder the crystallization of the soft segment, so the crystallization behavior of the aqueous polyurethane film is still close to the crystallization behavior of the pure soft segment, the crystallization of the product with good performance. To the sulfonate type polyurethane emulsion homemade preparation of the base material of water-based polyurethane adhesive for a shoe. The study found that the the sulfonate type polyurethane emulsion as the base material, together with the 0.4% defoamer, wetting and dispersing additive of 0.4%, 2.0% crosslinking agent, obtain comprehensive performance shoes aqueous polyurethane adhesive Adhesives.
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