Polyvinyl acetate-butyl acrylate latexes

Surfactant Interactions in Polyvinyl Acetate and Poly (vinyl acetate-butyl acrylate) Latexes... 

Recent investigations have shown that the behavior and interactions of surfactants in a polyvinyl acetate latex are quite different and complex compared to that in a polystyrene latex (1, 2). Surfactant adsorption at the fairly polar vinyl acetate latex surface is generally weak (3,4) and at times shows a complex adsorption isotherm (2). Earlier work (5,6) has also shown that anionic surfactants adsorb on polyvinyl acetate, then slowly penetrate into the particle leading to the formation of a poly-electroyte type solubilized polymer-surfactant complex. Such a solubilization process is generally accompanied by an increase in viscosity. The first objective of this work is to better under-stand the effects of type and structure of surfactants on the solubilization phenomena in vinyl acetate and vinyl acetate-butyl acrylate copolymer latexes. 

Transmission electron microscopy of latex film replicas showed that the polyvinyl acetate latexes did not undergo further gradual coalescence upon ageing at room temperature (37), as had been reported earlier (40). The addition of butyl acrylate, even in the 89 11 vinyl acetate-butyl acrylate molar ratio, however, was sufficient to cause further gradual coalescence of the latex films (37). 

There are a variety of thickening agents (thixotropes) designed for different applications. In aqueous and latex adhesives and sealants, such as acrylics, polyvinyl acetate, butyl, and natural rubber, frequently used types include ... 

The results showed that all batch polymerizations gave a two-peaked copolymer compositional distribution, a butyl acrylate-rich fraction, which varied according to the monomer ratio, and polyvinyl acetate. All starved semi-continuous polymerizations gave a single-peaked copolymer compositional distribution which corresponded to the monomer ratio. The latex particle sizes and type and concentration of surface groups were correlated with the conditions of polymerization. The stability of the latex to added electrolyte showed that particles were stabilized by both electrostatic and steric stabilization with the steric stabilization groups provided by surface hydrolysis of vinyl acetate units in the polymer chain. The extent of this surface hydrolysis was greater for the starved semi-continuous sample than for the batch sample. 

Vinyl Acetate, Homo- and Copolymer Latexes Vinyl Acetate Comonomer (butyl acrylate, ethylene, vinyl ester of versatic add) Partially Hydrolyzed Polyvinyl Alcohol Sodium Bicarbonate Hydrogen Peroxide (35%) Sodium Formaldehyde Sulfoxylate Water 70.0-100.0 0.0-30.0 6.0 0.3 0.7 0.5 80.0... 

In the hot-melt type, two principal polymer types are used polyolefin and ethylene co-polymer based and polyester and polyamide type. In the solvent-based type, the most prominent are neoprene (polychloroprene)-based solvent and latex types, and polyvinyl acetate emulsions. For pressure-sensitive adhesives, the most favored are acrylic adhesives and butyl rubber/polyisobutylene types. 

Journal of Polymer Science Polymer Physics Edition 39, No.14, 15th July 2001, p.1659-64 EFFECT OF RESIDUAL WATER AND FREE VOLUME ON THE GLASS-TRANSITION TEMPERATURE AND HEAT CAPACITY IN POLYSTYRENE/POLYVINYL ACETATE-CO-BUTYL ACRYLATE STRUCTURED LATEX FILMS... 

The dispersion of fibers in polymer latex to prepare composite has been reported for poly(6-hydroxyoctanoate) (PHO) [101, 102], polyvinylchloride (PVC) [103], waterborne epoxy [104] and polyvinyl acetate (PVAc) [94]. Most of the works focus on the use of non-polar, non-water-sensitive polymers, while keeping an aqueous media for the processing of the films to preserve the dispersion of the nanoparticles. In their pioneering work, Favier et al [94] adopted the technique of solvent casting using a synthetic latex obtained by the copolymerization between styrene (35 wt%) and butyl-acrylate (65 wt%) (poly(S-co-BuA)). Nanowhiskers were dispersed in the latex and evaporated. The nanocomposite films were obtained by water evaporation and particle coalescence at room temperature, that is at a temperature higher than Tg of poly(S-co-BuA), around 0 C. 

Bentonite thickening agents are used in various water based adhesives, caulks and sealants including those based on proteins and starch, polyvinyl acetate emulsions, natural rubber latexes, acrylic emulsions, neoprene emulsions, butyl emulsions, nitrile emulsions, and SBR emulsions. 

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