Synthesis and characterization of pH-responsive water-dispersed nanohydrogels of cross-linked polyacrylamide-co-polyacrylic acid Article uri icon

abstract

  • In the following article, stable nanohydrogels (NHGs) of poly (acrylamide-co-acrylic acid) (PAAm-co-PAA) were synthesized by batch polymerization (BP) and semicontinuous (SP) polymerization processes. As crosslinking agents, N,N′-methylenebisacrylamide (NMBAM) and ethylene glycol dimethacrylate (EGDMA) were used; docusate sodium salt (AOT) was used as a surfactant. The initiators employed in this work were 2,2′-Azobis(2-methylpropionamidine) dihydrochloride (V-50), potassium peroxydisulfate (KPS), peroxydisulfuric acid diammonium salt (APS), and dibenzoyl peroxide (BPO). The compositions of acrylamide/acrylic acid (AAm/AA) (90/10, 70/30, 50/50, w/w), the type of a crosslinking agent, and the type of initiator on pH response of water-dispersed NHGs were investigated. The NHGs were characterized by dynamic light scattering (DLS). Latexes with average particle size (Dpz) from 53 to 125 nm were obtained using NMBAM and EGDMA by BP polymerization processes. In contrast, NHGs synthesized by SP polymerization processes showed a Dpz ranging from 73 to 125 nm using NMBAM and EGDMA. On the other hand, the Dpz of the NHGs dispersed in water was found to be from 126 to 302 nm with NMBAM and EGDMA, respectively. Furthermore, the Dpz of the NHGs depended on the pH; higher pH values produced high Dpz values. The spherical morphology was maintained at the studied pH. © 2022 Society of Plastics Engineers.

publication date

  • 2022-01-01