Preparation of CO₂/N₂‐Triggered Reversibly Coagulatable and Redispersible Polyacrylate Latexes by Emulsion Polymerization Using a Polymeric Surfactant

Abstract

We report here a novel approach for making reversibly coagulatable and redispersible polyacrylate latexes by emulsion (co)polymerization of methyl methacrylate (MMA) using a polymeric surfactant, poly(2-(dimethylamino)ethyl methacrylate)(10) -block-poly(methyl methacrylate)(14) . The surfactant was protonated with HCl prior to use. The resulted PMMA latexes were readily coagulated with trace amount of caustic soda. The coagulated latex particles, after washing with deionized water, could be redispersed into fresh water to form stable latexes again by CO(2) bubbling with ultrasonication. The recovered latexes could then be coagulated by N(2) bubbling with gentle heating. These coagulation and redispersion processes were repeatable by the CO(2) /N(2) bubbling.

CO2‐Responsive Polymers

“…In order to overcome these problems, Zhu's group used commercially available N,N ‐dimethylaminoethyl methacrylate (DMAEMA) featuring a tertiary amine group with good stability against hydrolysis. This monomer was employed in the synthesis of a CO 2 ‐switchable block copolymer PDMAEMA‐ b ‐PMMA that was used as a surfactant for the preparation of PMMA latexes 90. However, this surfactant has to be protonated with HCl to be utilized in the polymerization.…”

Carbon nanotubes, graphene, and their derivatives for heavy metal removal

“…Besides that, polymers, especially those with electron-donating or alkaline groups, are increasingly applied to various carbon nanoadsorbents. They have many advantages over other materials, such as tailored molecular weight, chain topology, and functional groups [152][153][154]. Moreover, they are usually nontoxic as a result of their large molecular size, which will dramatically reduce the secondary pollution [155,156].…”

Highly CO2/N2-Switchable Zwitterionic Surfactant for Pickering Emulsions at Ambient Temperature

“…Their use facilitates product separation, transportation and storage, saving energy and material costs. [2][3][4][5][6][7] There have been a significant number of switchable surfactant structures reported in literature. The external stimuli utilized has included radiation, redox reagents, acids/bases, magnetism, temperature 1 and, more recently, gases such as CO 2 .…”