Synthesis of acryloyl copolymer core–shell microspheres with antibacterial activity and surface cationic effects

With the increasing risk of bacterial infections, antimicrobial materials have been paid attention and rapidly becoming the main components for alleviating bacterial pathogens, while synthetic polymer antibacterial materials play a crucial role. In this work, a series of acryloyl copolymer core–shell microspheres (AcCPMs) with cationic groups on its surface were synthesized by using acrolyl cationic monomers, methyl methacrylate and styrene through two-step polymerization and in-situ assembly. The micro-morphologies, structures and sizes of AcCPMs were characterized by SEM, TEM, XPS, FT-IR and dynamic light scattering. And the antibacterial activity was also evaluated against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). It indicated that all of AcCPMs have antibacterial activity, and the highest antibacterial rate was 97.0%, because the structure–activity relationship of AcCPMs, including alkyl chain length, cationic groups and the type of anions in quaternary ammonium salts affected their microstructure and antibacterial activity. In summary, the microstructure and antibacterial activity of the acryloyl copolymer core–shell microspheres could be adjusted by varying alkyl chain length and cationic groups. The method of preparing microspheres could be used to synthesize antibacterial coatings, and acryloyl copolymer core–shell microspheres could be applied in biomedical and environmental area.