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With a sound environmental laws and regulations and strengthen the awareness of environmental protection , the use of solvent-based paints is restricted . Waterborne polyurethane (WPU) have excellent mechanical properties and non-polluting , has been widely used in many fields . However, the performance of waterborne polyurethane alone can not meet people's needs, such as latex from thickening of the poor, low-solids , water and poor . To improve the performance of waterborne polyurethane emulsion and coating , expanding its scope of application , must be appropriately modified WPU . At present, the commonly used acrylate monomer way through graft copolymerization modified waterborne polyurethane . This method , although water-based polyurethane water , solvent resistance, however, it will affect the degree of crosslinking of the graft emulsion stability , the emulsion crosslinking density due to low water resistance and other mechanical properties remain as solvent-based polyurethane . So far, still no comprehensive performance polyurethane water-based paint is perfect . Therefore, the search for a new modified approach to improve its water resistance and mechanical properties, has very important significance. This topic firstly carbodiimide - uretonimine -modified 4,4 ' - diphenylmethane diisocyanate (MDI-100HL), polyester polyol (JW2044), dimethylol propionic acid (DMPA), trimethylolpropane (TMP) and ethylenediamine (EDA) as the main raw material, through the legal system since the waterborne polyurethane emulsion . Optimize the preparation of waterborne polyurethane systems and process conditions . Excellent bonding ability of an epoxy resin , high modulus , high strength, excellent adhesion, low shrinkage and water resistance, chemical resistance , etc., an epoxy resin was synthesized (E-44) The aqueous modified polyurethane emulsion . The effects of adding epoxy way , adding volume and various hydrophilic
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