Thickeners, coatings

The presence of the electrolyte is required to provide a pathway for the current and, in urban areas, this is commonly ironfll) sulfate formed as a result of attack by atmospheric SO2 but, in seaside areas, airborne particles of salt are important. Because of its electrochemical nature, rusting may continue for long periods at a more or less constant rate, in contrast to the formation of an anhydrous oxide coating which under dry conditions slows down rapidly as the coating thickens. 

S Sg/L Flocculation, selective flocculation, slime coatings, thickening... 

In HEC-thickened formulations, low-shear-rate viscosities increase with decreasing latex particle size. This effect has been a major limitation in formulating small-particle latices. The phenomenon appears to arise from electro viscous, hydration, or flocculation effects, not a depletion layer mechanism. Associative thickeners achieve efficient viscosity in coating formulations via participation in synthesis and formulation surfactant micelles to form pseudo macromolecules and via an ion-dipole interaction between the cations of surface carboxylate groups on the latex and the ether linkages of the associative thickener. Generally, an excess of synthesis surfactant is found in the production of small-particle latices. The achievement of lower viscosities in small-particle ( 100 nm) latex coatings thickened with associative thickener appears to occur by extensive disruption of the polymer hydrophobe s participation in intermicellar networks. 

A Regular monitoring and maintenance Regular monitoring and anti-corrosive coating thickening ... 

Uses Filler for plastics thixotrope, antisedimentation agent in epoxy casting resins, polymethylmethacrylate and acrylic casting, coating and molding materials, water-reducible coatings thickener for aq. systems, other polar liqs., cosmetics... 

Applications artificial fiber (food supplement), artificial tears, food (emulsifier, thickener), glue, mortar, paper, pharmaceutical (controlled release, scaffolds, tablet coating, thickener) Shen, H Ma, Y Luo, Y Zhang, Z Dai, J, Colloids Surf. B Biointerfaces, 135, 332-8, 2015. 

Uses Film-former for hair-sprays and fixing lotions suspending agent, dispersant, thickener, stabilizer, adhesion promoter for coatings thickener and protective colloid in inks binder in dry mortar and filling compds. emulsifier and protective colloid in crop protection prods. 

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