Journal of Polymer and Biopolymer Physics Chemistry. 2014, 2(3), 50-54DOI:
Abstract: The rheological properties of drilling fluids modified with three biopolymers – carboxylmethyl cellulose (CMC), xanthan gum polysaccharide (xanplex D), and polyanionic cellulose (PAC-R) have been studied. The effect of concentration of the biopolymers on the drilling fluid was also reported. The modified drilling fluids were found to obey Herschel-Bulkley rheological model. The fluids were also found to be pseudo-plastic with shear thinning behaviour. Polyanionic cellulose showed the highest shear rate and shear stress than carboxylmethyl cellulose and xanplex D. This can be attributed to the straight open long chain structure of PAC-R and its ability to interact with water, solids and with itself. It also acted as a better viscosifier because of the more negative charge it carries. Also, the formulation of biopolymer drilling fluid with bentonite has proven to improve the viscosity than that encountered in normal conventional drilling fluids.