Titanate coupling agent effects on nonaqueous Co2Z ferrite suspensions dispersion

Co₂Z ferrite powders with the chemical composition 3Ba_0.5Sr_0.5O·2CoO·12Fe₂O₃ have superior high frequency magnetic properties. However, Co₂Z ferrite powders are difficult to apply to practical processes because of agglomeration induced by the strong magnetic attraction between particles. In this study, Co₂Z ferrite powder pretreatment using a titanate coupling agent—Neopentyl (dially)oxy tri(dioctyl)pyrophosphate titanate (Lica 38) on the sedimentation and rheological behavior is investigated. The bonding mechanisms between ferrite powder, Lica 38, and dispersant (KD1) are studied using diffuse reflectance Fourier transform infrared spectroscopy is used to explain the difference in the rheological and sedimentation behaviors of untreated and titanate coupling agent-modified ferrite powders. The affinity of Co₂Z ferrite and dispersants could be substantially enhanced by coating a titanate- coupling agent onto the ferrite surface. The coated layer could prevent particles from agglomerating from magnetic interaction.