Synthesis of a Dendrimer as Rheological Modifier for Deep-Water Drilling Fluids and Study of its Interaction with Organo-Clay at Different Temperatures

As the influence of large temperature range during deep-water drilling on rheological properties of water-in-oil emulsified drilling fluids, a dendrimer synthesized from a dodecyl dibasic acid and triethylenetetramine was introduced as a rheological modifier to get a flat-rheology. The product was characterized by infrared spectroscopy and its interaction with organo-clay was studied with sedimentation experiment, optical microscope, X-ray diffraction (XRD), Transmission electron microscopy (TEM), and rheological test. The results showed that the dendrimer can improve the dispersion of organo-clay in oil and increase the distance between layers. What’s more, the addition of dendrimer can balance the yield point of base slurry (consisted of mineral oil, aqueous solution of 30wt% CaCl 2 , mixed emulsifier, and organo-clay) at 4 ° C and 65 ° C.