Effect of crosslinker to monomer ratio on the adhesion and size distribution of silver nanoparticles grown on poly (methacrylic acid) microspheres

Abstract

In this study poly methacrylic acid (MAA) microparticles were synthesized with variations in methylene-bis-acrylamide (MBA), with MBA in the role of the crosslinker. The as produced microparticles serve as substrates for the growth of silver nanoparticles while evaluating the effect of different crosslinker content. Each formulation was assessed in terms of silver nanoparticle adhesion, size distribution and silver quantity. Experimental evidence reveals that while incorporating crosslinker above 20 wt% with respect to the monomer, silver nanoparticle adhesion to the polymer surface increases, whereas in formulations above 35 wt% microparticle morphology hinders silver ion binding and the subsequent formation of silver nanoparticles. In addition, TEM microcopy combined with image classification analysis reported that in the range of 20–35 wt% MBA content, silver nanoparticle size distribution can be tuned. Evidently, MBA content between 20 wt% and 35 wt% (in relation to MAA) exhibits a dynamic state where carboxylic acid terminated functional side groups and amino-terminal side groups provide a synergistic effect in silver ion binding thus opening a functional pathway towards the controlled synthesis of silver nanoparticles.