Synthesis And Application Of Silicone Modified Waterborne Polyurethane

In recent years,with the development of society,people's awareness of environmental protection and the strict restrictions on volatile organic compounds(VOC)in environmental regulations of various countries,water-based polyurethane and its modified materials as environmentally friendly materials,and in many fields It has been rapidly developed with a wide range of applications.This topic uses isophorone diisocyanate(IPDI),polyether(PEG1000),N-methyldiethanolamine(MDEA)as the main raw materials,and synthesizes waterborne polyurethane through prepolymerization,chain extension,neutralization and emulsification.An emulsion having good water resistance and film formability was obtained,and the optimum synthesis scheme was determined.By studying the formulation and conditions of the polymerization process(R value,temperature and time of prepolymerization reaction,amount of MDEA and modification conditions),comprehensively consider their effects on reaction rate and product performance,and reduce side reactions as much as possible.Under the conditions,the optimal synthesis process of the aqueous polyurethane is determined as follows:R value:2.0,pre-polymerization temperature:65°C,chain extension temperature:80°C,pre-polymerizationtime:2h,chain extension time:1h,amount of MDEA :5% and the degree of neutralization:100%.The amino siloxane is modified by hydrophilic chain extension onto the prepolymer chain to modify the aqueous polyurethane.The optimum temperature for the modification reaction is 45 ° C,and the optimum time is 1.5h and the modifier dosage:6%.The synthesized WPU was characterized by infrared,water resistance,thermogravimetry,particle size and electron microscopy(SEM).The synthesized WPU was tested by infrared,water resistance,thermogravimetry,particle sizeand electron microscopy (SEM).The results showed that WPU and modified WPU products were synthesized,and the water resistance and fixing ability of the modified WPU are better than before the modification.