In situ Formation of Silver Nanoparticles in Photocrosslinking Polymers
Yajun Cheng, Diana N. Zeiger, John A. Howarter, Xinran Zhang, Nancy Lin, Joseph M. Antonucci, Sheng Lin-Gibson
Nanocomposites of difunctional methacrylate polymer/silver nanoparticles have been synthesized by coupling photoinitiated free radical polymerization with in situ silver ion reduction. A polymerizable methacrylate bearing a secondary amino function group, 2-(tert-butylamino)ethyl methacrylate (TBAEMA), was used to increase the solubility of the silver salt (silver 2-ethylhexanoate) in the hydrophobic resin system by forming Ag-N coordination bonds, leading to a homogeneous dispersion of the silver salt in the unpolymerized resin mixture. Fourier transform infrared spectroscopy (FTIR) revealed that the silver ion reduction had no significant effect on the degree of vinyl conversion of the methacrylate. X-ray photoelectron spectroscopy (XPS) measurements showed an increased silver concentration at the composite surface compared to the expected concentration based on the total amount of silver salt added. Furthermore, the surface silver concentration plateaued when the silver salt mass fractions was 0.08 % or greater. Composites with low amounts of silver salt (< 0.08 % by mass) exhibited comparable mechanical properties to those containing no silver. Transmission electron microscopy (TEM) confirmed that the silver nanoparticles formed within the polymer matrix were nanocrystalline in nature and primarily ≈ 3 nm in diameter, with some large particle aggregates. Composites containing silver nanoparticles were shown to reduce bacterial colonization with as little as 0.03 % (by mass) silver salt, and additional amounts of silver salt did not further decrease the surface colonization. With a substantial effect on bacterial growth and minimal effects on mechanical properties, the in situ formation of silver nanoparticles within methacrylates is a promising technique to synthesize antibacterial nanocomposites for biomedical applications.
, Zeiger, D.
, Howarter, J.
, Zhang, X.
, Lin, N.
, Antonucci, J.
and Lin-Gibson, S.
In situ Formation of Silver Nanoparticles in Photocrosslinking Polymers, Biomacromolecules, [online], https://doi.org/10.1002/jbm.b.31793
(Accessed May 17, 2022)