Study On The After-treatment Of A-olefin Polymer

Because of high stability in storage and adding convenience ofα-olefin polymer drag reducing agent, there are many focus on developing the new typeα-olefin polymer drag reducing agent suspending.α-olefin polymer, however, is very sticky and its grains are readily conglutinated together, it is necessary to coat the surface ofα-olefin polymer grains to avoid conglutination. At present, the method in common use is physical coating, for example, adding a suitable amount dispersant inα-olefin polymer grains prevents the grains from conglutinating. However,α-olefin polymer grains are not dispersed perfectly through the simple isolation, there is significant demand for better methods to disperse theα-olefin polymer grains well.Combination of physical and chemical coating is used to coatα-olefin polymer grains in this paper. After coated by urea-formaldehyde modified polyvinyl alcohol Fistly and then dispersed by dispersant B,α-olefin polymer grains are dispersed perfectly. During the experiments, a good coat is choosen and the appropriate ratio of all components in suspending is obtained, meanwhile, all kinds of performances achieved by coating are compared with that by dispersed. At last, the principle of theα-olefin polymer grains stability is studied via Infrared light, TEM and Zeta potentiometre.The results indicated that electrostatic repulsion between grains plays the main role duringα-olefin polymer grains disperse, urea-formaldehyde modified by polyvinyl alcohol, not only sticky but also very steady, is good for the dispersion ofα-olefin polymer grain. When the proportion of formaldehyde and urea is 2:1, the ratio of urea-formaldehyde toα-olefin polymer grain is 1:3 and the amount of dispersant B in suspending ( 35% wtα-olefin polymer grains ) is 2 g,α-olefin polymer grains dispersed by combination method show higher dispersing property and longer storage period than that obtained by traditional physical coating.