Synthesize And Modified Study Of The Waterborn Polyurethans Emulsification

Waterborne polyurethanes (WPU) are popular because they are non-toxic, non-flammable and do not pollute air or water, at the same time, which can meet very demanding performance requirements. Waterborne polyurethanes are replacing conventional solvent-borne polyurethane as the tendency and emphasis of paint industry. At present, waterborne polyurethanes have been widely used in fabric finish, leather finish, high quality building coatings, and coatings of wood and furniture, etc.In this paper, WPU were prepared using polyether polyatomic alcohol and based on the synthesizing polyether waterborne polyurethanes, using inter-emulsification mechanism,we carried out the modified study by methylα-methacrylate(MMA),styrene(St) andα-methacrylate(MMA) /styrene(St) complex to improve paint membrane water resistance and hardness.According to the present information about it, the synthesis techniques were fully researched with a series of parallel experiments test. The factors were considered, such as the method of preparation, the pretreatment to the raw materials and the temperature. The relationship between the factors above and the sample's properties was researched. The series of polyester WPU which was using 1, 4-butanediol (BDO) as chain extender were prepared. The impact of the dosage of DMPA to the properties of the waterborne polyurethane latex, and the film of rate of elongation, water resistance was researched. We also considered the extent of neutralization and the ratio of TDI and PBAG.In order to increase much more the water resisitance and hardness of waterborn polyurethane, and homologous increasing the wearbility, on the basis of the synthesized waterborn polyurethane, we prepared a series of modified WPU using polyether polyatomic alcohol, carried out the modified study by methyl a-methacrylate (MMA),styrene(St) anda-methacrylate(MMA) /styrene(St) complex, searched after the influence of monomer, initiator, emulfifing, assistants with the paint membrane synthesized and modified waterborn poIyurethanes(WPU) of rate of elongation and water-resistance, and analyed the paint membrane synthesized and modified waterborn polyurethanes (WPU) of heat resistance and molecular structure. Based on the comparison and analysis, we obtained the modified waterborn polyurethane with the optimal capability and the prescription and the reaction condition which provides the theories for industrialization.