Styrene acrylic latex

The control and reproducibility of particle size and particle size distribution is important to the quality of acrylic and styrene-acrylic latex products. Particle size has large effects on latex viscosity and the rheology of formulated products and may also exert subtle effects on the end-use peiformaiKe properties. The particle size is controlled primarily by the choice and amount of surfactant, or by the use of seed latexes. A recoit article [32] addresses the use of surfactants to control particle size in semi-continuous acrylic polymmzations. Many surfactants are reconunended by surfactant manuhicturras for the preparation of acrylic and styrene-acrylic latexes [33]. Sodium lauryl sulfate, sodium dodecylbenzene sulfonate, sulfosuccinates and the aUtylphonl ethoxylates ate typical. The patent literature contmns many discussions of the use of single [34] or multiple [3S] polymer seed latexes to control particle size. 

The composition and process details of most commercial acrylic and styrene-acrylic latexes are proprietary, and there is such variety that it would be difficult to select one or two as typical examples. A sampling of polymerization processes from the patent literature follows an acrylic latex for aqueous... 

Particle and colloidal stability, that is, lack of sedimoitation, stratification or phase separation, coagulation or flocculation, or changes in viscosity when the latex is stored, shipped, pumped, sprayed, formulated, etc. is required for most end-uses of acrylic and styrene-acrylic latexes. Such stability is primarily determined by the type and level of surfactants or other stabilizers and specialty or auxiliary monomers used. The trade-off is that functional materials contributing to particle and colloidal stability generally also increase water or moisture sensitivity, and there is an optimum balance for each end-use application. 

Chem. Descrip. Barium phosphosilicate pigment Uses Tannin stain inhibiting pigment used in protective coatings, acrylic latexes, styrenated acrylic latexes, and solv. based alkyds Features Nonretractive provides high level of performance and compat. in variety of resin systems... 

Chem. Descrip. Styrene-acrylic latex resin CAS 9010-92-8... 

Chem. Descrip. 50% Methacrylamidoethylethyleneurea, 20% methacrylic acid, 30% water, 2000 ppm hydroquinone inhibitor Uses Monomer for emulsion polymerization of acrylic, vinyl-acrylic, and styrene-acrylic latex paints with improved wet adhesion, wet scrub resist., solv. resist. adhesion promoter in water- and solv.-based coatings and adhesives... 

Waterborne dispersed polymers include both synthetic polymer dispersions and natural rubber. Synthetic polymer dispersions are produced by emulsion polymerization. A substantial part of the synthetic polymer dispersions is commercialized as dry products these include SBR for tires, nitrile rubbers, about 10% of the total PVC production, 75% of the total ABS and redispersable powders for construction materials. Carboxylated styrene-butadiene copolymers, acrylic and styrene-acrylic latexes and vinyl acetate homopolymer and copolymers are the main polymer classes commercialized as dispersions. The main markets for these dispersions are paints and coatings, paper coating, adhesives and carpet backing. 

Bragaiifa et al. [97] showed the importance of the clay lamellar intercalation and exfoliation to define the material mechanical properties of nanocomposites. In this study, montmorillonite clay with different interlamellar cations (NaL Li+, K+, and Ca +) was mixed with styrene-acrylic latex and dried to produce nanocomposites. An ultra-thin cut of the sample was analyzed by ESI-TEM. The elemental maps of carbon, silicon, and calcium were used to identify the polymer, clay, and cation domains, as presented in Fig. 8.13. 

Emulsifier for the generation of very fine particle size vinyl acetate, acrylic and styrene-acrylic latexes. Resulting films have superior water-resistant properties. 

Polymer Areas Primary emulsifier for acrylic, vinyl acetate and styrene-acrylic latexes. Very fine particle size emulsions with excellent water-resistant properties. 

Polymer Areas Emulsion polymerization. Effective in styrene-butadiene, poly(vinyl chloride), poly(vinyl acetate), acrylic, and styrene-acrylic latexes. Imparts excellent mechanical, thermal and electrolyte stability, low coagulum and small particle latexes. 

Three types of latex formulations have been prepared. The first formulation is an acrylic latex from methyl methacrylate, butyl acrylate and acrylic acid using sodium lauryl sulfate and Synperonic NP20 (an ethoxylated nonylphenol) as surfactants. The second formulation is a vinyl acrylic latex from vinyl acetate, butyl acrylate and sodium vinyl sulfonate with sodium lauiyl sulfate as the surfactant. The third formulation is a styrene acrylic latex from styrene, butyl acrylate and methacrylic acid with sodium lauryl sulfate as the surfactant. Three experimental latex formulations analogous to the three above were also prepared with AMPS sodium salt replacing acrylic acid, sodium vinyl sulfonate and methacrylic acid respectively. 

Emulsion polymerization is the leading technique to produce colloidal polymer dispersions. Carboxylated styrene-butadiene copolymers, acrylic and styrene-acrylic latexes, and vinyl acetate homopolymer and copolymers are the main polymer classes produced by this technique. These products are commercialized as dispersions and as dry products. 

Uses Emulsifier in vinyl acrylic, acrylic, and styrene acrylic latexes food-pkg. 

Uses Emulsifier for acrylic, vinyl/acrylic and styrene/acrylic latexes in food-contact applies. 

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