甲酰化炭黑的制备及在钠盐溶液中分散性研究

Preparation of formylated carbon black and its dispersive property in sodium salt solutions

采用Vilsmeier-Haack和Reimer-Tiemann反应,在硝酸氧化改性炭黑表面修饰甲酰基,制备甲酰化功能炭黑。通过傅里叶变换红外光谱、扫描电子显微镜及热失重对甲酰化炭黑的表面官能团、形貌特征及热力学性质进行分析,并利用紫外-可见吸收光谱考察了不同温度条件下甲酰化炭黑在钠盐溶液中的分散性能。结果表明:炭黑表面含有一定量的醛基等基团;800℃条件下,炭黑甲酰化后质量损失率由4%升到10%左右;甲酰化后炭黑的粒径基本保持不变,但聚集程度增大;在2.0 mol/L的亚硫酸氢钠溶液和十二烷基苯磺酸钠溶液中,甲酰化炭黑的分散性较好且升温有利于分散。

Two types of formylated carbon blacks(FV-CB and FR-CB)are prepared through Vilsmeier-Haack and Reimer-Tiemann reactions,respectively,referring to the modification of formyl group onto the surfaces of HNO3-oxidized carbon black(O-CB).Then formyl CB is performed by Fourier transform infrared spectroscopy(FT-IR),scanning electron microscope(SEM),and thermogravimetric analysis(TG)to study the surface functional groups,thermodynamic and morphological properties.Furthermore,UV-visible spectroscopy is employed to uncover the dispersion performances in routine sodium salt solutions at different temperatures.The results show that there are some new groups on both FV-CB and FR-CB surfaces as aldehyde units.TG results presented the total mass loss ratio of formyl CB increasing to about 10%from 4%at 800℃after formylation treatment.The particle size of formyl CB remained basically unchanged,but its aggregation degree enhanced.Good dispersion was observed in 2.0 mol/L sodium bisulfite and sodium dodecylbenzene sulfonate solutions respectively,and both dispersion effects could be promoted by raising temperature.