Description: polyurea crosspolymer-1 is the complex, crosslinked polymer formed by the reaction between four different isocyanates and pei-45. the isocyanates used are a trimer of hexamethylene diisocyanate (hdi), saturated methylene diphenyldiisocyanate (smdi), the monourea of hdi trimer with ammonium cyclohexylaminopropanesulfonate, and hdi.