Influence of fluorinated segments of variable length on the thickening properties of a model HASE skeleton

Abstract

Introduction of fluorocarbon segments in an associative thickener copolymer (ethyl acrylate (EA)/ methacrylic acid/macromonomer) was achieved by the substitution of EA with either trifluoroethyl acrylate, 2-perfluorobutylethyl acrylate, or 2-perfluorooctylethyl acrylate. The thickening properties were evaluated by rheological flow experiments in aqueous medium as well as in 10 wt % of sodium dodecyl sulfate (SDS) aqueous solution. Whereas in the literature no particular attention is devoted to the impact of the ethylene moieties in hydrophobically modified alkali-soluble emulsion (HASE) skeleton, our study reveals they contribute significantly to the performances when modified by an incompatible fluorocarbon segment. Moreover, the synthesis process has a huge influence by inducing a specific distribution of the fluorinated acrylates in the macromolecule. The amount of substitution is also important and even 20 mol % of EA substituted reveals a great impact on the rheological properties of the copolymer solutions. Whereas an SDS aqueous medium generally destroys almost all the hydrocarbon interactions from the macromonomer, the total replacement of ethyl groups by trifluoroethyl groups with a cosolvent process, leads to emulsions with an equivalent thickening effect than the reference hydrocarbon HASE used. This result is quite encouraging for research work on the synthesis of HASE with increased biocompatibility.

Preparation, rheology, and film properties of polyacrylate latex using amphiphilic macroreversible addition‐fragmentation chain transfer agents as surfactants

“…Furthermore, sample Entry 10 (pH 7.0, solid content 30%) presented shear‐thinning behavior in the entire shear rate range. Actually, polyacrylic products have been widely applied in waterborne coatings as the thickening agents because of their inherent advantages of low cost and ease of application leading to great economic benefit . However, the most common method to prepare polyacrylic thickening agents, that is, inverse emulsion polymerization, would cause pollution because of the large amount use of organic solvents.…”

“…Actually, polyacrylic products have been widely applied in waterborne coatings as the thickening agents because of their inherent advantages of low cost and ease of application leading to great economic benefit. 24,25 However, the most common method to prepare polyacrylic thickening agents, that is, inverse emulsion polymerization, 26 would cause pollution because of the large amount use of organic solvents. In addition, a lot of time will be spent for choosing suitable thickening agents that have well compatibility with the latexes.…”

Vegetable oil based fatty amide as hydrophobes in associative thickener

“…1 Associative thickeners employed in waterborne coatings include cellulose derivatives, hydrophobically modified alkali soluble emulsions (HASE), and hydrophobically modified ethoxylated urethanes (HEURs). Hydrophobically modified cellulosics, 1,6 acrylics, 1,7,8 and urethanes 1,7,[9][10][11] constitute the building block materials for such associative thickeners. The associative thickening mechanism is primarily due to interactions between the hydrophobic portions of thickener and latex particles, but is also influenced by surfactants, coalescing solvents, and pigments.…”

Properties of powdered associative alkali‐swellable acrylics thickeners synthesized by precipitation polymerization

“…As an important type of rheological modifier, alkali‐swellable acrylics thickener (ASAT) has been widely applied in waterborne coatings, adhesives, pharmaceuticals, person care product, and so on . Light crosslinked polyacrylic acid or polymethacrylic acid is a very common ASAT.…”

“…As an important type of rheological modifier, alkali-swellable acrylics thickener (ASAT) has been widely applied in waterborne coatings, adhesives, pharmaceuticals, person care product, and so on. [1][2][3][4][5] Light crosslinked polyacrylic acid or polymethacrylic acid is a very common ASAT. The use of a crosslink agent results in formation of polymer with three-dimensional network throughout each particle and the polyacids, which exhibit expansion upon neutralization in water.…”