Synthesis of well‐defined, functionalized polymer latex particles through semicontinuous emulsion polymerization processes

Abstract

ABSTRACT:The design of a semicontinuous emulsion polymerization process, primarily based on theoretical calculations, has been carried out with the objective of achieving overall independent control over the latex particle size, the monodispersity in the particle size distribution, the homogeneous copolymer composition, the concentration of functional groups (e.g., carboxyl groups), and the glasstransition temperature with n-butyl methacrylate/n-butyl acrylate/methacrylic acid as a model system. The surfactant coverage on the latex particles is very important for maintaining a constant particle number throughout the feed process, and this results in the formation of monodisperse latex particles. A model has been set up to calculate the surfactant coverage from the monomer feed rate, surfactant feed rate, desired solid content, and particle size. This model also leads to an equation correlating the polymerization rate to the instantaneous conversion of the monomer or comonomer mixture. This equation can be used to determine the maximum polymerization rate, only below or at which monomer-starved conditions can be achieved. The maximum polymerization rate provides guidance for selecting the monomer feed rate in the semicontinuous emulsion polymerization process. The glass-transition temperature of the resulting carboxylated poly(n-butyl methacrylate-co-nbutyl acrylate) copolymer can be adjusted through variations in the compositions of the copolymers with the linear Pochan equation.

Influence of carboxyl groups on the particle size and rheological properties of polyacrylate latices

“…The carboxyl group's distribution in the latex was determined by conductometric titration according references [11,12] .…”

Environmentally‐Friendly Acrylates‐Based Polymer Latices

“…Th e emulsion technique was adopted by several scientists [56][57][58][59] to synthesize the crosslinked copolymers because, in emulsion polymerization, crosslinkers allow the control of particle morphology and enhance the mechanical properties of latexes used for paints and coatings. Th e kinetic and mechanistic features of emulsion polymerization are strongly refl ected in molecular weight and its distribution, chemical composition, and product properties.…”

Synthesis of carboxylic acid functionalized nanoparticles by reversible addition–fragmentation chain transfer (RAFT) miniemulsion polymerization of styrene

“…The PS nanospheres prepared by this method have functionalities of carboxyl acid and carboxylic anion, and thus the magnitude of zeta potential and conductivity values of the latex are led to be greater. Although a titration method could be used for a quantitative analysis of carboxylic acid groups on the surface of the polymer colloids, it is technically quite difficult for tiny polymer nanoparticles [38] since the adsorbed surfactant should be removed from the particle surfaces. Therefore, the zeta potential and conductivity values were used to indirectly confirm the existence of carboxylic acid groups on the surface of the PS nanospheres.…”