Water-borne latex

Scotts technology (17) uses fluid-bed (Wurster column) technology to apply polymeric coatings to a number of fertilizer substrates including urea, potassium nitrate, potassium sulfate, and monoammonium phosphate (MAP). The coating material is appHed as a water-borne latex onto the fluidized substrate. As the substrate is fluidized with warm air (40—50°C), water is driven off and the latex coalesces into a continuous film around the fertilizer particle. The particular latex compositions used have selected glass-transition and blocking temperatures, which enable quick removal of the water before the soluble fertilizer core dissolves. This obviates the need to use precoats prior to the latex appHcation. 

It is known(J ) that when hydrophobe-modified W-SPs such as those in Figure 1 are formulated in water-borne latex coatings a significant time period 048 hours) is required to reach steady state viscosities this does not happen when either MC, HPMC, HEC... 

Polymerizing acrylic monomers in the presence of oil-modified polyurethane leads also to a grafting onto the polyacrylics, resulting in dispersions suitable for stable water-borne latexes with good adhesion properties and fair hardness properties [103]. 

Particle deformation and polymer diffusion can only occur at temperatures above the glass transition temperature of the polymer. Final coatings, however, are required to be at temperatures considerably below the glass transition temperature. To get around this problem, it is common to add plasticizers to water borne latex dispersions to lower the glass transition temperature of the constituent polymer during the film formation process. Subsequent evaporation of the plasticizer results in a hard final coating. A common plasticizer is 2,2,4-trimethyl-l,3-pentanediol monoisobutyrate, usually referred to as Texanol Ester Alcohol. 

Uses Coalescing agent in water-borne latex coatings active solvent for solv.-bome coatings solvent, coupling agent in cosmetics, toiletries Properties Colorless liq. low odor mod. water sol. m.w. 176.2 sp.gr. 0.922 dens. 7.70 Ib/gal vise. 4.3 cSt vapor pressure 0.12 mm Hg b.p. 212.0 C flash pt. (Seta) 190.0 F surf. tens. 27.6 dynes/cm Dowanol EB [Dow]... 

Uses Corrosion inhibitor, pigment for water-borne latexes, water reducible alkyds, high solids coatings Regulatory FDA compliant... 

Exxate solvents are efficient coalescent aids for water-borne latex coatings. Water is used in water-borne coatings as a diluent or latent solvent in combination with an active solvent. A latex emulsion (individual resin particles) affords a continuous protective film after the resin particles coalesce during the drying process. Successful film formation requires a solvent coalescent aid that softens the resin particles allowing individual particles to form a continuous film. The coalescent solvent must remain in the film until after the water evaporates from the coating. The type of latex often determines which coalescent solvents affords the best film properties. 

Typical composition of a water-borne rubber adhesive Latex polymer 100 phr... 

PVA in, 25 617 setting speed of, 25 579-580 smectites application, 6 697t solution, 1 532-534 structural, 1 534-545 styrenic block copolymers in, 24 714 use of latex in, 14 711-712 vinyl acetate polymers in, 25 578-583 viscosity of, 25 581 water-borne, 25 475 Adhesive systems, microencapsules in, 16 460... 

An acrylate modified vinyl chloride - vinylidene chloride latex copolymer (Haloflex 202) has been developed in our laboratory (1,2) specifically for the preparation of water-borne anti-corrosive primer paints. This carefully designed copolymer, hereafter... 

Substrates, Paints and Coatings. Both flash rusting and underfilm darkening studies exployed a white, pH 4.5, primer formulation (see Appendix), designated as Standard, based upon Haloflex 202, a chlorine-containing vinyl acrylic latex. A zinc phosphate free formulation, designated as Non-Standard, of pH6 was prepared by substitution of zinc phosphate for barytes. The comparison paints were a commercial butyl acrylate-methyl methacrylate water borne primer, formulated at pH 9, and a solvent based chlorinated rubber primer. 

Acrylic latex sealants. Basic acrylic latex sealant formulations were compounded in a sigma blade mixer, as shown in Table 3. The water-borne silanes were then incorporated into a base. Standard wet and dry peel adhesion determinations from various substrates were performed periodically in accordance with ASTM C794-8. 

Volatile organics in the coating film are deemed unacceptable from the environmental point of view and are giving way to water-based inhibitive primers. Some examples of water-based primers are of the acrylic latex type, as well as epoxies and water-borne... 

Cohesives are essentially contact adhesives. Cohesives are water borne products typically formulated with natural rubber latex polymers modified with other polymers such as acrylics and acetate polymers to yield the necessary peel and block resistant properties. Cohesives are used for a wide variety of applications on various paper products and films particularly for confectionery packaging. 

ATRP polymerization (Mn=5750) was chain extended with St to yield a block copolymer with Mn=21,400 and an Mw/Mn=1.15, after 24 h and 78% monomer conversion, as shown in Fig. 29 [121], Although the authors showed that both statistical and block copolymers could be prepared in the water-borne system, the latex stability was often low and phase separation was observed. Success in these polymerizations depends strongly on the nature of the additives present (i. e., surfactant, macroinitiator, etc.) [121,212]. 

It is particularly good for colloids, emulsions and particles. Samples separated thus far include lattices, latex aggregates, silica sols, alkyd resins, perfluorocarbon emulsions, milk, carbon particles, hematite, clay, water-borne particles, liposomes, subcellular particles, viruses, and polymerized proteins. 

Other water-borne coatings include water-soluble emulsions, dispersions, and latex resins. Water-soluble resins are rare because most resins derived from vegetable oils are insoluble in water. The true emulsions are based on the emulsification of the oil or alkyd through either the action of a surfactant or a resin that has a surfactantlike character. The alkyd emulsions are readily prepared and can be used for OEM coatings and architectural applications. The submicron size droplets are stabilized by the thickeners (El-Aasser Sudol, 2004 Landfester, 2005 Landfester et al., 2004 Tsavalas et al., 2004 Weissenborn Motiejauskaite, 2000a,b). In dispersions, the resin is a solid and is dispersed in water. The latex resin is usually vinyl acetate, styrene, acrylates, or methacrylates radically copolymerized in a micelle to form particles 0.1 pm in diameter (Bloom et al., 2005 Brister et al., 2000 Jiratumnukul Van De Mark, 2000 Thames et al., 2005). 

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