The Design Of Fluoride, Silicon, Boron Modified Waterborne Polyurethane Molecular Structure And Research The Performance Of Materials

Waterborne polyurethane has been widely used in many fields such as paint, textile, printing, leather and so on, due to its environmentally friendly and excellent integrated performance. However, hydrophilic group(or segment) contained in the molecular chain lead to a poor water resistance; moreover, poor heat resistance and flame retardant caused by most linear structure has limited the application of waterborne polyurethane in the actual. In this paper, the performance of modified Waterborne polyurethane based on 3-triethoxysilyl-1-Propanamine(KH-550)、boric acid 、 octafluoropentanol 、 3-methacryloxypropyltrimethoxysilane( KH-570) 、dodecafluoroheptyl methacrylate(DFMA) was characterized.(1)A series of silicon and boron modified waterborne polyurethanes(SBWPUs) were synthesized based on polyester glycol, toluene diisocyanate(TDI), 2,2-bis(hydroxymethyl)propionic acid(DMPA), boric acid and 3-triethoxysilyl-1-propanamine(KH-550) through prepolymerization method and characterized by infrared spectrometer, contact angle measurement instrument, cone calorimeter and smoke density tester. The results show that the stable emulsion was obtained when R was 2, DMPA content was 4%. Furthermore, the water resistance, flame retardant, smoke suppression performanceand, mechanical properties of SBWPUs were improved effectively.(2)Fluorine and silicon terminated waterborne polyurethane WFPUs were prepared by octafluoropentanol and 3-triethoxysilyl-1-propanamine(KH-550), groups contained in molecular chain were characterized by FTIR, and the performance of WFPUs were characterized by contact Angle measurement instrument, cone calorimeter and mechanical property test. The results show that the stable emulsion was obtained when the contents of KH-550 and octafluoropentanol were less than 5%, 8%, respectively. Moreover, reduced water absorption and improved flame retardancy were obtained.( 3) A series of waterborne polyurethane-acrylic composite emulsion(FSWPUAs) were synthesized based on polyester polyol, methyl methacrylate(MMA), dodecafluoroheptyl methacrylate(DFMA), 3-methacryloxypropyltrimethoxysilane( KH-570) through unsaturated compound sealing method. And the influences of initiator amounts, polymerization temperature, polymerization time and monomer ratio to the properties of emulsion were discussed. And then, FTIR was employed to study the product structure, water absorption, flame retardancy and mechanical properties were also studied. The results show that the product obtained under 80 ℃, polymerization time of 12 h, and 0.8 wt % azobisisobutyronitrile(AIBN) as initiator possess better appearance and stability. And the water resistance and flame retardancy of modified waterborne polyurethane were improved to some extent.