Latex polymers used

Hercules Res A. [Hercules] Resin dispersion tackifier for acrylic-latex polymers used in label, tape, and construction adhesives. 

Latex polymers used in a variety of applications are generally prepared over a wide range of hydrophobicities. 

Synthetic emulsion polymers account for approximately 70% of the U.S. consumption of acrylate monomers. Major end uses for these latex polymers are coatings (32%), textiles (17%), adhesives (7%), paper (5%), and floor poHshes (3%). The U.S. producers of acryflc copolymer emulsions include Rohm and Haas, Reichhold, National Starch, Union Carbide, Air Products, Unocal, B. F. Goodrich, and H. B. Fuller. 

Emulsion Polymerization. Emulsion polymerization is used commercially to make vinyhdene chloride copolymers. In some apphcations, the resulting latex is used directiy, usually with additional stabilizing ingredients, as a coating vehicle to apply the polymer to various substrates. In other... 

Polymer-supported catalysts often have lower activities than the soluble catalysts because of the intraparticle diffusion resistance. In this case the immobilization of the complexes on colloidal polymers can increase the catalytic activity. Catalysts bound to polymer latexes were used in oxidation reactions, such as the Cu-catalyzed oxidation of ascorbic acid,12 the Co-catalyzed oxidation of tetralin,13 and the CoPc-catalyzed oxidation of butylphenol14 and thiols.1516 Mn(III)-porphyrin bound to colloidal anion exchange resin was... 

The viscoelastic behavior of concentrated (20% w/w)aqueous polystryene latex dispersions (particle radius 92nm), in the presence of physically adsorbed poly(vinyl alcohol), has been investigated as a function of surface coverage by the polymer using creep measurements. From the creep curves both the instantaneous shear modulus, G0, and residual viscosity, nQ, were calculated. 

The reduction in porosity, decreased water content, and air entrainment that results when latexes are used in mortar and concrete mixes make them much more resistant to freezing and thawing conditions than conventional mortar and concrete. Figure 6.17 presents the freeze-thaw durability in water (-18 to 4°C) of combined water-and dry-cured SBR-, PAE- and EVA-modified mortars [98], The frost resistance of mortars made with these latexes is markedly improved even at polymer-cement ratios of 5%. However, an increase in the polymer-cement ratio does not necessarily produce further improvement in freeze-thaw resistance. EMM and EMC, when exposed to outdoor conditions involving freeze-thaw, UV radiation and carbonation show better weatherability when compared with conventional mortar and concrete. 

Seed polymerization using a polystyrene latex was used by Gaschler et al. (3) to prepare aqueous styrol-butadiene polymer dispersions. 

The polystyrene seed latex was monodispersed. Even after several grow-ups (polymerizations) the final 1650 A latex was monodispersed. Hydrodynamic chromatography on the 1650 A latex gave a mean diameter of 1660 a with a size variance as small as for normal polystyrene latex standards (typical standard of 1760 8 with a standard deviation of 23 a). The final latex particle size could be accurately predicted from the initial particle size and the total amounts of monomer and polymer used. 

Most latex-modified mortars and concretes have good adhesion to most substrates (tile, stone, brick, steel and aged concrete) compared to conventional mortar and concrete. In general, bond strength in tension and flexure increases with an increase in the polymer-cement ratio, irrespective of the type of polymer used [87,94,98],... 

Quality Control of Latex Polymerization Using Hydrodynamic Chromatography. Latex polymers are most commonly manufactured in a large vessel with all the product being removed at the end of the polymerization reaction. This so-called batch polymerization process... 

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