Properties of latex

Abstract Emulsion homopolymers and copolymers (latexes) are widely used in architectural interior and exterior paints, adhesives, and textile industries. Colloidal stabihzators in the emulsion polymerization strongly affect not only the colloidal properties of latexes but also the fdm and mechanical properties, in general. Additionally, the properties of polymer/copolymer latexes depend on the copolymer composition, polymer morphology, initiator, polymerization medium and colloidal characteristics of copolymer particles. 

The first work on the emulsion copolymerization with a macromonomer has been reported by Ito et al. [132] for styrene using PEO macromonomer 49. Subsequently, several research groups have reported the synthesis and some properties of latex particles containing PEO chains from 26,27,36,50-52, attached to their particles surface [132-140]. Ottewill and Satgurunathan [134] and West-by [ 135] reported the preparation of such particles in a multistage emulsion po-... 

Physico-chemical Properties of Latexes Obtained by Polymerization of... 

Composition and Properties of Latexes used in the Study of Particle Structure... 

Ohama, Y. (1987), Principle of Latex Modification and Some Typical Properties of Latex-Modified Mortars and Concretes, ACI Materials Jounal, November-December, pp. 511-518. 

The final properties of latex coatings are dependent on the mechanism of film formation and how the film forms. For example, the development of mechanical strength is a direct consequence of polymer chain inter-diffusion. Prediction of this strength is only possible from an understanding of the transformations occurring on the particle length scale. Here, the three major transformations in latex film formation are briefly outlined. 

Winnik, M.A. The formation and properties of latex films. In Emulsion polymerization and emulsion polymers, Lovell, P., El-Aasser, M.S., Eds. John Wiley and Sons Ltd, 1997 468-515. 

It has been proved that incorporation of carboxylic acid groups in the polymeric chain has a significant effect on colloidal properties of latex, processability, and end-use property. Carboxylated styrene-butadiene latexes (XSBR) are prepared via batch emulsion copolymerization with different amounts of acrylic acid in the absence of emulsifier. They are among the most important polymeric colloids, and can be used as binder in paper coatings, carpet backing, paints, and nonwoven. There are several studies on the preparation and properties of XSBR latexes. 

Over the years, Dionex has developed a wide variety of latex agglomerated resins to meet various needs in IC. A review of these developments is given in a book by Weiss [16]. Properties of latex columns are summarized in Table 3.6. 

Processes of mechanical and dielectrical relaxation as well as structural-morphological self-organization in these systems under vibrowave treatment have been already described in our previous work [8]. In the presented work the major attention is paid to an estimation of elastic-strenght properties of latex films and their IR-spectra. Figures 1 and 2 illustrate the dependence of physicomechanical properties of films on their composition, and also change of these dependences at simple mechanical influence (stirring of a latex by means of a mechanical stirrer) and under vibrowave treatment. 

Effect of Solvents on Properties of Latex and Electrodeposition Paints... 

It was observed that intermediate compositions dried slower than the unblended constituents. The mechanical properties of latex blends comprising low and high particles, the film formation ability, and the comparison of results to classical theory of polymer blends containing hard particles have been reported by Lepizzera et al. [1997], This is one of the few studies in the literature that has attempted to correlate emulsion blend properties with empirical/theoretical relationships previously available in the open literature. 

Water Sensitivity. Improvement in the water sensitivity and improved barrier properties of latex film has been an important goal of many coatings chemists. One of the first publications (38) on HEUR-thickened... 

Latex-modified mortar and concrete have a markedly improved water retention over ordinary cement mortar and concrete. The water retention is dependent on the polymer-cement ratio. The reasons for this can probably be explained in terms of the hydrophilic colloidal properties of latexes themselves and the inhibited water evaporation due to the filling and sealing effects of impermeable polymer films formed. Accordingly, a sufficient amount of water required for cement hydration is held in the mortar and concrete and, for most latex-modified systems, dry cure is preferable to wet or water cure. This is also examined in Sec. 2.1. 

Effect of the Nature of INfoterials. The nature of polymers in latexes mainly depends on monomer ratio in copolymers and the type and amount of plasticizers. The properties of latexes such as mechanical and chemical stabilities, bubbling, and coalescence on drying are dependent on the type and amount of surfactants and antifoamers and the size of dispersed polymer particles. 

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