Synthesis of High Solid‐Content Latex using Alkali‐Soluble Resin as Sole Surfactant

Abstract

Summary: A novel polymerization procedure to synthesize latex stabilized by alkali‐soluble resin (ASR) is detailed. According to this process, latexes with a high solid content and low viscosity are obtained using a substantially lower amount of ASR when compared with existing techniques. Similar rewet properties were found for the latexes obtained by a standard process and for the one obtained by the process described in this work.Comparison of the particle size distributions obtained by conventional emulsion polymerization (○) and by miniemulsion polymerization (□).magnified imageComparison of the particle size distributions obtained by conventional emulsion polymerization (○) and by miniemulsion polymerization (□).

Macromolecular surfactants for miniemulsion polymerization

“…Do Amaral et al studied the low-shear viscosity of latexes prepared by miniemulsion polymerization using either low-molar mass surfactants or PVA as stabilizers and fitted the experimental values with the equation proposed by Sudduth which includes empirical parameters accounting for the surface coverage of the particles [142][143][144]. Their results indicate that the presence of macromolecular chains at the surface of the latex particles can provide significantly higher viscosities to the latex suspensions for volume fractions exceeding 30%.…”

“…Viscosity level and rheological behaviour of the continuous phase Initial droplet size [43,50,149] Rheological properties of the final latex [107,142] Stirring of the reaction medium Kinetic irreversibility of adsorption at oil/water and solid/water interfaces Ostwald ripening of the initial emulsion [25,37] Colloidal stability of the final particles [53] Formation of a dense superficial layer on the initial droplets and final particles…”

High solid content latex: Preparation methods and application

“…Recently, many research groups have obtained HSC latex, including Greenwood [31,32], Ai [7,8], Chu [42][43][44][45], Schneider [56][57][58], Salima Boutti [53][54][55], Leiza [66], do Amaral [68][69][70], Wei [73] and Zhang et al [76][77][78][79][80][81]. Generally speaking, most HSC latexes were prepared by using the following four methods: conventional emulsion polymerization, miniemulsion polymerization, self-emulsification polymerization, and concentrated emulsion polymerization.…”

“…do Amaral et al [69,70] are also successful in obtaining highly concentrated aqueous polymer dispersions by combining miniemulsion polymerization with semi-continuous emulsion polymerization. As shown in Fig.…”

Desenvolvimento de látices nitrílicos carboxilados

“…

e aerossóis; têxteis (não-tecidos) e nas indústrias de papel e couro [3,5,7] .Este trabalho trata de um estudo sobre o desenvolvimento de látex nitrílico carboxilado com alto teor de sólidos e baixa viscosidade através de processo de polimerização em emulsão.Não é econômico submeter látices poliméricos a técni-cas convencionais de concentração, tais como evaporação, cremagem e centrifugação, para a obtenção de látices com teor de sólidos acima de 55% [6,[8][9][10][11][12]14,16,[17][18][19][20] . Esses látices tendem a apresentar viscosidade elevada, o que representa um obstáculo na aplicação desses materiais em composições de revestimento de superfícies e adesivos, que necessitam de uma composição de látex suficientemente fluida e estável para permitir a sua aplicação como um filme fino.

…”