Synthesis of silver nanoparticles in surfactant-free light-cured methacrylate resins

SILVANA V. ASMUSSEN; CLAUDIA I. VALLO

COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2015 vol. 466 p. 115 - 124

0927-7757

tThe present study describes a simple method for preparing stable, highly dispersed spherical silvernanoparticles (Ag NPs) in surfactant-free methacrylate resins. Colloidal dispersions of silver in methacry-late resins were obtained by in situ reduction of silver nitrate. The reducing agents were hydroquinone(HQ), hydroquinone methyl ether (MEHQ) and 2,6-di-tert-butyl-para-cresol (BHT), which are added tothe resins to prevent premature polymerization. The obtained finely dispersed Ag NPs, that were 5?10 nmin diameter, were maintained in a stable colloidal state for more than nine months at ambient temper-ature. UV?vis and TEM analysis revealed that the particle size did not change with the reaction time.Moreover, UV?vis spectra and TEM micrographs of samples stored for 9 months, showed no drasticchange in average particle size. From these studies, it is concluded that the methacrylate resins used asreactive solvent act as efficient particle stabilizers preventing particle coalescence and thereby enablinglong term stability. The dispersions Ag NPs/methacrylate resins were photoactivated with 0.5 wt% of2,2-dimethoxy-2-phenylacetophenone and were photo polymerized with a UV light source of irradiancecentred at 365 nm. The effective utilization of the surfaces of the formed metal nanoparticles is an advan-tage associated with nanoparticles formed via a surfactant-free synthesis method. The proposed processoffers the possibility to use these synthesized materials for the production of colour filters for opticaldevices and biomaterials with improved antimicrobial properties.The present study describes a simple method for preparing stable, highly dispersed spherical silvernanoparticles (Ag NPs) in surfactant-free methacrylate resins. Colloidal dispersions of silver in methacry-late resins were obtained by in situ reduction of silver nitrate. The reducing agents were hydroquinone(HQ), hydroquinone methyl ether (MEHQ) and 2,6-di-tert-butyl-para-cresol (BHT), which are added tothe resins to prevent premature polymerization. The obtained finely dispersed Ag NPs, that were 5?10 nmin diameter, were maintained in a stable colloidal state for more than nine months at ambient temper-ature. UV?vis and TEM analysis revealed that the particle size did not change with the reaction time.Moreover, UV?vis spectra and TEM micrographs of samples stored for 9 months, showed no drasticchange in average particle size. From these studies, it is concluded that the methacrylate resins used asreactive solvent act as efficient particle stabilizers preventing particle coalescence and thereby enablinglong term stability. The dispersions Ag NPs/methacrylate resins were photoactivated with 0.5 wt% of2,2-dimethoxy-2-phenylacetophenone and were photo polymerized with a UV light source of irradiancecentred at 365 nm. The effective utilization of the surfaces of the formed metal nanoparticles is an advan-tage associated with nanoparticles formed via a surfactant-free synthesis method. The proposed processoffers the possibility to use these synthesized materials for the production of colour filters for opticaldevices and biomaterials with improved antimicrobial properties.