the effect of initiator and weight ratio on dynamic-mechanical properties of multilayer latex ipn with core/shell morphology

Polymers have good dynamic mechanical properties and high damping capacity dueto their viscoelastic nature, especially in the glass transition range, and are considereda good damper with a loss factor greater than 0.3 and a peak temperature range of atleast 60-80ºc. two of the best ways to expand the damping range are fabricating thecore/shell latex particles with a specific morphology and using interpenetrating polymernetworks in the core and shell sections. the aim of this study is to synthesize andinvestigate the dynamic-mechanical properties of interpenetrating polymer networkswith core/shell morphology. a set of multilayer core/shell/shell latex particles withstyrene-acrylic monomers were synthesized by varying the initiator (thermal initiatorand redox initiator) via semi-continuous emulsion polymerization. in this study,synthesized particles were characterized with fourier transform infrared (ft-ir)spectroscopy, the morphology was determined by transfer electron microscopy (tem),and the size and size distribution were investigated via dynamic laser scattering (dls),which represent nano-scale particles with narrow distribution. the damping propertiesof the formed films were studied by dynamic mechanical analysis (dma). the factorsaffecting the formation of poly(styrene/methyl methacrylate/butyl acrylate)-based core/shell particles, including the type of initiator and layer mass ratio, were discussed.the results showed that the ipn core/shell latex particles with a thermal initiatorexhibited the best damping properties, with a broad effective damping range (tanδ >0.3). the influence of the layer mass ratio on damping was also explored in this work.