Acrylic latex properties

Acrylic-Latex Properties. The choice of acrylic latex is critical to obtaining true contact adhesive performance. The first criterion is that the latex and phenolic must yield a stable blend when combined directly, with pH modification, or with the aid of additional surfactants. The properties of the acrylic resin particles then become important A latex resin which is too hard and/or does not properly coalesce may never develop contact tack in the course of drying a latex resin which is too soft may exhibit tack even when fully dry, but may not have adequate cohesive strength for most applications. 

Uses Coemulsifier, dispersant for alkaline industrial cleaners, resins, waxes stabilizer for vinyl/acrylic latexes Properties Solid HLB 17.1 99% cone. 

Table 6.11 Effect of glass transition temperature Tg on the properties of acrylic-latex-modified mortar (Ma and Brown)...

Formation of solubilized surfactant-latex complexes can influence the properties and performance of vinyl acrylic latexes prepared with NaLS and other penetrating type anionic surfactants. Such complexes seem to affect glass transition temperature and film coalescence process (12). 

Viscoelastic Properties of Acrylic Latex Interpenetrating Polymer Networks as Broad Temperature Span Vibration Damping Materials... 

An extremely soft, hydrophilic, acrylic latex with outstanding durability properties, for use with CALIBAN F/R P-44, P-53, P-66. 

Generally, modification is made by adding approximately a 15% level of acrylic latex. Modified asphalt displays improved properties. Acrylic-modified asphalts are used for parking lots, driveways, low-voliune off-highway streets and highway shoulders. 

Ash is a chemically stable inorganic material. Thus, there is a potential for their application as a construction material. Possible applications of ashes reported in the literature include asphalt, cement concrete block, road construction, and melt slag (1-3). Recently, we carried out studies on the possible application of ashes from incinerated paper sludges for interlocking blocks. Acrylic latex was employed to improve the properties of cement mortar or concrete modified with ashes. Our results are partly reported in this paper. 

The effect of structural memory in a wave field has been exsemplarily studied by the IR-spectroscopy method on films made from mixtures of butadiene-styrene and acrylic latex as models of polymeric membranes. The strengthening of the interphase interaction in heterophase systems that can cause change of their local and transmitting mobility has been observed. It has been shown, that the response of polymeric dispersed systems and compositions on influence of nonlinear vibrations proves their influence on deformation properties, like orientation phenomena in solid polymers (where Rebinder s effect can take place) that it is possible to consider as a way of polymer modifications, including the obtaining of nanicomposites, polymeric biocarriers, etc. 

Table I compares typical test results for low-, mid-, and high-effective molecular weight thickeners in a vinyl-acrylic latex paint. Many of the same trends are present with cellulosic and HE UR thickeners when the effective molecular weight designation for HEUR thickeners is used. As the effective molecular weight of an HEUR increases, Stormer thickening efficiency, roller spatter, and water resistance increase, whereas ICI viscosity decreases. The major difference between these two thickener types is in their low-shear behavior. As effective molecular weight increases, cellulosic paints improve in leveling and decrease in sag resistance. HEUR paints decrease in leveling and improve in sag resistance. Other property differences between these two thickener types are highlighted in Table II.

Typical physical properties of an acrylic latex emulsion suitable for use with cement are given in Table 5. 

Similarly the disadvantages of PC are the stress cracking and chemical sensitivity. Stress cracking can be treated as a part of impact properties and a simple solution may thus be addition of ABS or ASA. On the other hand, to improve the solvent resistance—a property that is particularly important in automobile applications—a semicrystalline polymer may be added. From Table 4.37, it is apparent that TPEs (e.g., PBT, PET) could provide that property, but they also lack warp resistance and impact strength. Hence an ideal blend for automobile application based on PC and TPEs should be impact modified with, for example, an acrylic latex copolymer. A schematic of preparation of this type of toughened blend introduced by GEC-Europe in 1979 under the tradename Xenoy is shown in Figure 4.41. 

J.C. Padget, J.P. Moreland, Use of A.C. impedance in the study of the anticorrosive properties of chlorine-containing vinyl acrylic latex copolymers, J. Coat. Technol. 55 (1983) 39—51. 

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. 

Yan et al. [52] explored the use of IPN techniques to produce a composite vinyl-acrylic latex. The first-formed polymer was produced using VAc and divinyl benzene (DVB), while the second formed polymer constituted a BA/DVB copolymer. In both cases the DVB was added at 0.4 wt%. They compared this product with another product, a bidirectional interpenetrating netwodc (BIPN) in which VAc was again polymerized over the first IPN. They noted that the compatibility between the phases was more pronounced in the BIPN than in the IPN as determined using dynamic mechanical measurements and C nuclear magnetic resonance spectroscopy. The concept of polymer miscibility has also been used to produce composite latex particles and thus modify the pafamance properties of VAc latexes. Bott et al. [53] describe a process whereby they bloid VAc/ethylene (VAc/E) copolymers with copolymers of acrylic acid or maleic anhydride and determine windows of miscibility. Apparently an ethyl acrylate or BA copolymer with 10-25 wt% AA is compatible with a VAc/E copolymer of 5-30 wt% ethylene. The information obtained from this woik was then used to form blends of latex polymers by polymerizing suitable mixtures of monomers into preformed VAc/E copolymers. The products are said to be useful for coating adhesives and caulks. 

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