摘要
石墨的分散是制备水性石墨导电涂料的关键技术,本文选用十二烷基硫酸钠(SDS)作为分散剂,制备了稳定性能较好的石墨-H2O分散液。通过测定石墨-H2O分散液的吸光度和Zeta电位,探讨了不同SDS添加量、pH值对石墨-H2O分散液稳定性的影响,并分析了作用机理。结果表明:SDS的添加量存在一个最佳值,以石墨质量为基准,SDS用量为3.5%时,分散液稳定性最好;分散液受pH值影响较大,pH值的增大促进了石墨表面酸性基团的离解并使SDS分子充分伸展,增大了石墨粒子间的静电斥力,分散液的稳定性增强;该体系中,主要通过静电斥力使石墨粒子稳定,Zeta电位绝对值与吸光度有良好的对应关系,Zeta电位绝对值越高,吸光度越大,分散液稳定性越好;石墨-H2O分散液的粒径分布及粘度曲线表明,加入SDS使石墨粒子在水中达到良好的分散。
Dispersion of graphite was the key technique for preparing the waterborne graphite conductive coating.SDS was chosen as a dispersant,and graphite-H2O dispersoid with high stability was prepared.Some potential factors related to the stability of dispersoid such as SDS content,pH value were studied by testing the Zeta potential and absorbency,and the mechanism was also analyzed.It was found that the good stability of dispersoid was achieved under the condition of adding 3.5%（w）of SDS based on the weight of graphite.It was indicated that pH value has a significant effect on the stability of the dispersoid,the increment of pH value is beneficial for the improvement of electrical repulsion between graphite particles,thus promoting the stability of the dispersion.The electrostatic repulsion supplied by SDS dispersed the graphite particles in this system.There is a corresponding relation between absolute value of Zeta potential and absorbency.It was resulted that higher the absolute value of Zeta potential and higher the absorbency,better the stability of the dispersoid.Viscosity curve and particles size distribution of graphite-H2O dispersoid showed the graphite particles reach a fine dispersive degree in water.
出处
《材料科学与工程学报》
CAS
CSCD
北大核心
2010年第2期208-211,225,共5页
Journal of Materials Science and Engineering
基金
国家部委科技资助项目(JPPT-1251)
关键词
分散
石墨
十二烷基硫酸钠
dispersion
graphite
sodium lauryl sulfate
