duolite a7 free base formaldehyde,polymerwithn,n’-bis(2-aminoethyl)-1,2-ethanediamineandphenol Phenol,formaldehyde,N,N’-bis(2-aminoethyl-1,2-ethanediaminepolymer Triethylenetetramine,formaldehyde,phenolpolymer formaldehyde/ phenol/ triethylenetetramine copolymer Duolite(R) A7 free base duolitea-7ion-exchangeresin Formaldehyde,polymerwithN,N’-bis(2-aminoethyl)-1,2-ethanediamineandandphenol