Measuring and modelling the peculiarities of aqueous‐phase radical polymerization

Abstract

The application of specialized pulsed-laser techniques has led to a vastly improved understanding of the kinetics of aqueous phase solution radical polymerization of water-soluble monomers. Propagation rate coefficients vary significantly with monomer concentration, an effect unique to the aqueous environment. In addition, the formation and reaction of mid-chain radicals affects polymerization rates, and thus polymer molar masses, in acrylamide and acrylic acid systems. This perspective provides an overview of these mechanistic peculiarities, which have been captured in kinetic models developed to represent the homopolymerizations of N-vinyl pyrrolidone, N-vinyl formamide, methacrylic acid, acrylic acid, and acrylamide over a wide range of conditions. The batch studies demonstrate the importance of these effects in aqueous polymerization and the validity of the rate coefficients taken from the independent kinetic studies.

Morphologies of microparticles of partially neutralized sodium polyacrylate by inverse suspension polymerization

“…The free radical polymerization of water soluble monomer such as AA and acrylamide has been known to deviate from the standard free radical polymerization kinetics, especially in the rate dependence of monomer concentration. For example, the reaction order with respect to monomer concentration has been observed to vary between 1.24 and 1.49 . It is to be noted that the scope of this work does not include the kinetic analysis of polymerization.…”

Viscosity monitoring study of the kinetics of aqueous‐medium N‐vinylpyrrolidone free‐radical polymerization

“…NVP stands among the most important types of water‐soluble monomers together with methacrylic acid and methacrylamides . Despite the wide application of this class of polymers, the understanding of the kinetics of these water soluble systems has lagged behind of those in organic systems . These aqueous‐medium systems have been the focus of a relatively small number of academic studies and considerable part of these works has focused on detailed kinetic investigations of the methacrylic and methacrylamides systems, while the N ‐vinyl amides still do not receive the same attention …”

“…and Stach et al, respectively. An overview of these mechanistic peculiarities for homopolymerization of water‐soluble monomers was recently presented by Preusser and Hutchinson …”

“…7 Despite the wide application of this class of polymers, the understanding of the kinetics of these water soluble systems has lagged behind of those in organic systems. 8 These aqueous-medium systems have been the focus of a relatively small number of academic studies and considerable part of these works has focused on detailed kinetic investigations of the methacrylic and methacrylamides systems, [9][10][11] while the N-vinyl amides still do not receive the same attention. 1 The initial development of the theory of the FRP of vinyl monomers was based mainly on the results of studies of the polymerization of weakly polar hydrocarbon monomers.…”

Estudo Cinético Da Polimerização Radicalar Da N-Vinil-2-Pirrolidona

“…Embora exista o esforço de alguns autores em explicar os mecanismos envolvidos na polimerização em solução aquosa da NVP (PREUSSER; HUTCHINSON, 2016;SANTANAKRISHNAN et al, 2011), não há trabalho que investigue a polimerização da NVP nas altas faixas de concentração utilizadas industrialmente. Assim, o objetivo do presente trabalho é investigar e propor um modelo capaz de representar o processo de polimerização desse monômero vinílicos em concentrações maiores que as estudadas na literatura.…”