CTAB对锌-镍合金基复合电镀液中PTFE分散性的影响

Effect of CTAB on dispersion of PTFE in zinc–nickel alloy-based composite electroplating bath

针对聚四氟乙烯(PTFE)在镀液中分散难的问题,以分散液中PTFE的润湿效果、Zeta电位以及PTFE的粒径分布为指标,研究了阳离子型表面活性剂十六烷基三甲基溴化铵(CTAB)添加量对PTFE在去离子水中分散性的影响。结果表明,随着CTAB用量的增大,PTFE的分散均匀性和稳定性改善,微米PTFE基本能够实现单分散。CTAB用量大于PTFE质量的3%后,PTFE在10 min内可被完全润湿。镀液中CTAB用量为3%时,可复合电沉积得到PTFE均匀分布的Zn–Ni–PTFE复合镀层,但需持续搅拌镀液,以确保PTFE均匀分散。

As for the hard dispersion of polytetrafluoroethylene(PTFE) powder in plating bath, the effect of the dosage of cetyltrimethylammonium bromide(CTAB, a cationic surfactant) on the dispersibility of PTFE in deionized water was studied by evaluating the wettability, zeta potential, and particle size distribution of PTFE in suspension. The results showed that the dispersion uniformity and stability of PTFE was improved with the increasing of the dosage of CTAB, and the micro-sized PTFE nearly achieved monodispersibility. PTFE could be completely wetted within 10 min when the mass fraction of CTAB is higher than 3% with respect to the mass of PTFE. A Zn–Ni–PTFE composite coating with uniform distribution of PTFE could be obtained when the dosage of CTAB was 3%. It is necessary to stir the bath continuously to ensure uniform dispersion of PTFE in it.