Cu(0)-Mediated Reversible-Deactivation Radical Polymerization of n-Butyl Acrylate in Suspension

Publication date: Available online 20 August 2018Source: PolymerAuthor(s): Mojtaba Enayati, Alireza AbbaspourradAbstractCu(0)-mediated reversible-deactivation radical polymerization of n-butyl acrylate was performed in suspension without the use of an organic solvent. In all cases, a 5 v% organic phase (monomer, initiator and ligand) was used with respect to 95 v% aqueous phase. Polyvinyl alcohol (PVA) as a suspension stabilizer has been shown to be able to control the polymerization for degree of polymerizations of 222 and higher. The polymerization reaction showed linear first order kinetics for a PVA concentration range of 1 to 10 wt%, leading to polymers with dispersities from 1.22 to 1.43. Conversions as high as 96% were obtained in 55 min. Scanning electron microscopy analysis of the suspensions confirmed the formation on micron-sized polymer particles dispersed in aqueous media, and that the size of the particles decreased with increasing PVA concentration. Rheometry measurements of the aqueous phase containing PVA before and after polymerization demonstrated the increase in the viscosity of the reaction mixture after polymerization. The difference between the viscosity of the PVA solution in water and the same solution after polymerization decreased as the PVA decreased, which indicates smaller particle sizes formed with increasing PVA content. All suspensions were stable over a period of three months storage at room temperature without any precipitation or sedimentat...
Source: Polymer - Category: Chemistry Source Type: research