The effects of some factors on the dynamic mechanical properties (DMS) of polystyrene/ poly (n-butyl acrylate) (PS/PBA) latex interpenetrating polymer networks(IPNs) were studied with Rheovibron Viscoelastometer. It was found that the DMS curves under different frequencies can not superpose each other by simple shifting. The glass transition region broadens with the increase of PS content in the latex IPNs
and the influence of crosslinking density on the latex IPNs is not the same as that of sequential IPNs. The possible reasons for these pheno-mena were discussed.