Carboxylic‐group distribution of carboxylated acrylate copolymer latexes with their properties in the presence of acrylic acid and monobutyl itaconate

Abstract

A series of carboxylated acrylate copolymer latexes were prepared via two different emulsion polymerization technologies with different carboxylic‐group distribution and morphologies. The effects of the emulsifier, the initiator, and the carboxylic monomers [acrylic acid (AA) or monobutyl itaconate (MBI)] on the total conversion of the monomers and the properties of acrylate latexes and films have been investigated. The distribution of carboxylic groups (−COOH) measured by conductometric titration shows that the concentration of surface –COOH (Cs) and embedded –COOH (Cb) both increase with the increase of the amount of carboxylic monomers. For the latexes containing AA, –COOH tends to distribute on the surface of latex particles and in the aqueous phase, whereas –COOH tends to concentrate inside the core of latex particles for the latexes containing MBI. Transmission electron microscopy demonstrates that the latex particles are regular with narrow size distribution and have significant differences in morphologies when different carboxylic monomers and polymerization technologies were used. The stability of latex is satisfactory through the results of common stability and zeta potential tests. Moreover, the water absorption and contact angle experiment tests also revealed that the water resistance of the latex films is good. Copyright © 2011 John Wiley & Sons, Ltd.

Role of acrylic acid in the synthesis of core‐shell fluorine‐containing polyacrylate latex with spherical and plum blossom‐like morphology

“…Figure shows the conductometric titration curve of latex with HCl solution (a) and the carboxyl groups distribution with different AA content (b). In Figure (a), the conductometric titration curve of latex with HCl solution is similar to other reports . The decrease of conductivity in part A and the increase in part D are ascribed to the neutralization of NaOH and the existence of excess HCl, respectively.…”

“…The carboxyl groups distributions (latex surface, aqueous phase, or buried in the latex) were determined by conductometric titration . First, the latex was diluted with water to a concentration of about 1.5%, and the pH was adjusted to about 11.5 by NaOH solution.…”

Partitioning of monobutyl itaconate and β‐carboxyethyl acrylate between organic and water phases

“…Although a few fundamental studies have been carried out concerning the behavior of MBI and β‐CEA in emulsion polymerizations, the distribution of these two new functional monomers between the organic and aqueous phases has not been investigated until now. The partitioning behavior of the carboxylic acids between the organic and aqueous phases depends on many factors such as temperature, pH, composition, type, and concentration of surfactant, etc .…”

Modification research on the peel strength of the acrylate emulsion pressure‐sensitive adhesives

“…Qu et al 10 reported the synthesis of a series of poly[(n-butyl acrylate)-co-(acrylic acid)] latexes with different particle sizes with changing levels of surfactant at the seed stage. 13,14 They can generally be divided into several categories: unseeded semibatch, 15 monomer-seeded semibatch, 12 and pre-emulsion-seeded semibatch 16 polymerizations. Xu et al 11 discussed the effect of the hard monomer (MMA) content on the adhesive properties of poly(butyl acrylate-co-methyl methacrylate-co-acrylic acid) latexes.…”

“…Semibatch polymerizations have always been used in these syntheses of acrylate emulsions. 13,14 They can generally be divided into several categories: unseeded semibatch, 15 monomer-seeded semibatch, 12 and pre-emulsion-seeded semibatch 16 polymerizations. However, no study to date has examined the effect of different semibatch processes on the peel strength of PSAs.…”