A polymeric polymer containing poly(oxyethylene)-amine and its application to preparation of silver nanoparticles. The polymeric polymer is prepared from poly(oxyethylene)-amine and a linker, for example, poly(styrene-co-maleic anhydride) (SMA) or dianhydride. The polymeric polymer can chelate silver ions and reduce them to silver atoms which are dispersed as nanoparticles. No additional reducing agent is needed and more than 30% of solid content of the nanoparticles solution can be achieved without aggregation. The prepared silver nanoparticles are both hydrophilic and hydrophobic and therefore are compatible with polymers.