摘要:
The molecular weight and molecular weight distribution of diverse ultra-high molecular weight water soluble polymers is rapidly determined based on apparent size by passage of extremely dilute samples of the polymer (1-250 ppm) through a column of nonporous packing whereby separation into molecular weight (apparent size) fractions is obtained predominantly based on flow (i.e., hydrodynamic chromatography). Detection of the extremely dilute sample polymer is accomplished, e.g., by tagging the polymer with a fluorescent agent and using a flow-through fluorometer detector. The molecular weight characterization of the polymers is determined independent or less dependent of the composition of the polymer by analyzing the sample in its nonionized form.
摘要:
The molecular weight and molecular weight distribution of diverse ultra-high molecular weight water soluble polymers is rapidly determined based on apparent size by passage of extremely dilute samples of the polymer (1-250 ppm) through a column of nonporous packing whereby separation into molecular weight (apparent size) fractions is obtained predominantly based on flow (i.e., hydrodynamic chromatography). Detection of the extremely dilute sample polymer is accomplished, e.g., by tagging the polymer with a fluorescent agent and using a flow-through fluorometer detector. The molecular weight characterization of the polymers is determined independent or less dependent of the composition of the polymer by analyzing the sample in its nonionized form.
摘要:
A stable water-in-oil emulsion of a hydrophobe associative copolymer of a water-soluble monomer such as acrylamide and a hydrophobic monomer such as dodecyl methacrylate is formed by subjecting a water-in-oil emulsion of the corresponding monomers to copolymerization conditions in the presence of an oil-soluble initiator such as cumene hydroperoxide. Such copolymers associate in aqueous media containing salts such as sodium chloride to increase the viscosity of such media.
摘要:
A suspending agent useful in a water-in-oil suspension polymerization process comprises a fumed silica particulate having a hydrophobic character and a hydrophobic polymer. The suspending agent is useful in providing uniformly sized aqueous fluid absorbent polymer beads.
摘要:
A suspending agent useful in a water-in-oil suspension polymerization process comprises a fumed silica particulate having a hydrophobic character and a hydrophobic polymer. The suspending agent is useful in providing uniformly sized aqueous fluid absorbent polymer beads.
摘要:
Quaternary carboxamide polymers such as N-(triethylammonium ethyl)acrylamide chloride are prepared by simultaneously contacting a carboxamide polymer with an aldehyde such as formaldehyde, a secondary amine such as dimethylamine and a quaternizing agent such as methyl chloride. By such method, quaternary carboxamide polymers useful in a variety of applications such as emulsion breaking and water clarification are readily prepared.
摘要:
Water-miscible monomers such as acrylamide are polymerized continuously to produce a concentrated solution of a high molecular weight polymer by passing a mixture of a water-immiscible organic liquid and an aqueous solution of at least 20 weight percent of the monomer through a tubular reactor, e.g., a polyethylene tube, having internal surfaces that are readily wetted by the hydrocarbon liquid and polymerizing the monomer in the reactor. The polymerized product is recovered as a water-in-oil emulsion wherein the polymer resides in the dispersed aqueous phase or as a solid strand which is a high solids aqueous solution containing at least 20 weight percent of the water-soluble polymer of the water-miscible monomer.