一种可再分散的纳米银/聚氨酯杂化材料的制备及表征

Synthesis and Characterization of Re-Dispersible Silver Nanoparticles/Polyurethane Hybrid Materials

以硬段含有二硫键的聚氨酯(APU)为稳定剂,NaBH4还原AgNO3原位生成了稳定性良好且可再分散的纳米银/聚氨酯复合材料。通过紫外、红外、热分析、透射电镜对材料进行了表征。紫外研究表明,随着AgNO3用量的增加,纳米银在420 nm处的特征紫外吸收峰强度也在增加,说明复合材料中纳米银的含量在增加。但是,当AgNO3量到达APU的10%后,纳米银的特征紫外吸收峰强度反而降低,说明APU的最大载银量(以AgNO3计)为10%。红外分析表明,APU硬段的的-SH与纳米银之间形成了共价键,起到了长期稳定纳米银的作用,所制备的材料也具有可再分散性能。

Re-dispersible nano-silver particle/polyurethane composites with long stability were prepared in situ using polyurethane with disulfide bond in the hard segment （APU） as stabilizer, silver nitrate as silver source and NaBH4 as reduction agent. The nanocomposites were characterized by UV-vis spectrum, FT-IR spectrometer, thermal gravity analysis （TGA） and transmission electron microscope （TEM）. UV-vis analysis show that the intensity of the absorpuon band at 420 nm increases with the amount of AgNO3 increasing. The intensity reaches the maximum value with 10 % AgNO3 adding to APU solution. It is demonstrated by FT-IR that the - SH in the hard segment of APU attaches covalently on the silver nanoparticles and stabilizes the nano-particle for a long time. The APU/nhno-silve composites can be re-dispersed in organic solvents.