Synthesis and mechanism study of gelatin grafted acetone formaldehyde sulphonates as oil-well cement dispersant

摘要

A novel dispersant, gelatin grafted acetone formaldehyde sulphonates (GAFS), was synthesized for oil-well cement. GAFS was synthesized by aldehyde ketone addition reaction, hydroxyl condensation reaction and Mannich amine methylation reaction, using gelatin, acetone, formaldehyde and sodium metabisulfite as the base materials. Functional groups and the molecular structure of GAFS were characterized by Fourier transform infrared spectroscopy. Evaluating experiments of GAFS mechanical properties and application performances were conducted. The results show that GAFS can be adsorbed on the cement particles tightly because of the electrostatic forces, and the adsorption amount of GAFS on cement particle surfaces is great. The adsorption of GAFS is spontaneous, and adsorption strength between GAFS and cement particles is high. GAFS can generate a great potential energy barrier, resulting in excellent dispersion performance. The adsorption of GAFS on cement particles is physical adsorption. Consequently, GAFS hardly influences the hydration reaction and imposes no retarding effect on the cement.