water-repellent treatment of textiles – wacker chemie in saudi arabia
High molecular weight (106) partially hydrolysed polyacrylamide (PHPA) has been prepared and its efficacy as viscosifier in water based drilling mud has been evaluated. When PHPA is added to bentonite mud system, it causes a viscosity hump indicating encapsulating effect. The breakdown
A class of water muds that use partially-hydrolyzed polyacrylamide (PHPA) as a functional additive, either to control wellbore shales or to extend bentonite clay in a low-solids mud. As a shale -control mud, PHPA is believed to seal microfractures and coat shale surfaces with a film that retards dispersion and disintegration.
