The Influence of Reaction Conditions on the Copolymer Composition in Inverse Miniemulsion

Abstract

Summary: Water‐soluble poly(2‐acrylamido‐2‐methylpropane‐1‐sulfonic acid‐co‐1‐vinylimidazole) (P(AMPS‐co‐1‐VIm)) and poly(2‐acrylamido‐2‐methylpropane‐1‐sulfonic acid‐co‐2‐(dimethylamino)ethyl methacrylate (P(AMPS‐co‐DAMA)) are studied as it is known that the copolymer composition is affected by pH of the monomer phase in inverse miniemulsion. The distribution of the basic monomers in the continuous and dispersed phase changes due to their degrees of protonation. The amounts of the monomers in the cyclohexane phase is determined by gas chromatography, the copolymer composition is studied by elemental and thermogravimetric analysis. An insight into the monomer distribution in the polymer is provided by simultaneous potentiometric and conductometric titration of polymer solutions.

Miniemulsion polymerization as a versatile tool for the synthesis of functionalized polymers

“…The polymerization was found to be faster at neutral pH values and higher molecular weight polymers were produced in miniemulsion compared to solution polymerization as a result of the confinement effect. The same group carried out a similar study with the copolymerization of 2-acrylamido-2-methyl-1-propanesulfonic acid and 2-(dimethylamino)ethyl methacrylate [ 26 ].…”

Synthesis of biocompatible and thermally sensitive poly(N‐vinylcaprolactam) nanogels via inverse miniemulsion polymerization: Effect of the surfactant concentration

“…To favor droplet nucleation and to preserve the stability of the size particles, miniemulsion polymerization can be used. Miniemulsion polymerization is a flexible route for synthesizing different kind of polymer hybrids 12. This polymerization process has been studied for years and can be basically defined as a procedure in which the polymerization mixture is dispersed into a continuous phase with an average size below one micrometer 13, 14.…”

Copolymerization of 2‐Acrylamido‐2‐methyl‐1‐propanesulfonic Acid and 1‐Vinylimidazole in Ethanol

“…The literature values of 1‐VIm ( Q = 0.11, e = −0.68)35 were used as a basis to calculate the Q and e values of AMPS and NaAMPS. Copolymerization parameters for the solution polymerization of AMPS with S ( r AMPS = 0.18 ± 0.08 and r S = 1.23 ± 0.28) were estimated under the same reaction conditions and used for the polymerization of AMPS with 1‐VIm without adjustment of the pH value33 utilizing the Kelen‐Tüdös approach36. Finally, the corresponding Q and e values for AMPS are Q = 0.3, e = 0.43, which were used as the basis to calculate the Q and e values of 1‐VIm.…”

“…Based on the work of Fischer, molar weights of 140 000–200 000 g · mol −1 were calculated for the poly(NaAMPS) homopolymers 38. However, the high viscosities of AMPS/1‐VIm copolymers suggest that they polymerized in inverse miniemulsion under basic, neutral, and acidic conditions which resulted in higher molar weights 33…”

“…Previous work focused on the synthesis and polymerization of the isolated salt AMPS/1‐VImH + and by polymerization of AMPS and 1‐VIm in inverse miniemulsion. However, there was not a clear understanding as to the reaction conditions effect on the polymer and its properties 31–34. We had noticed previously that the pH of the reaction medium influences the properties of the resulting polymer.…”