derivatives thereof having at least one n h bond are suitable in accordance with the instant invention however the preferred phenylenediamines are the p phenylenediamines having the structure str1 wherein r 1 r 2 r 3 and r 4 are the same or different and are hydrogen alkyl aryl alkaryl or aralkyl groups with the proviso that at least one of r 1 r 2 r 3 or r 4 is hydrogen more preferably the alkyl aryl alkaryl and aralkyl groups have one to about twenty carbon atoms the alkyl aryl alkaryl and aralkyl groups may be straight or branched chain groups exemplary p phenylenediamines include p phenylenediamine wherein r 1 r 2 r 3 and r 4 are hydrogen n phenyl n alkyl p phenylenediamines such as n phenyl n 39 methyl p phenylenediamine n phenyl n 39 ethyl p phenylenediamine n phenyl n 39 n propyl p phenylenediamine n phenyl n 39 isopropyl p phenylenediamine n phenyl n 39 n butyl pphenylenediamine n phenyl n 39 isobutyl p phenylenediamine n phenyl n 39 sec butyl p phenylenediamine n phenyl n 39 tert butyl p phenylenediamine n phenyl n 39 n pentyl p phenylenediamine n phenyl n 39 n hexyl p phenylenediamine n phenyl n 39 1 methylhexyl p phenylenediamine n phenyl n 39 1 3 dimethylbutyl p phenylenediamine n phenyl n 39 1 4 dimethylpentyl p phenylenediamine n phenyl n 39 n 39 dialkyl p phenylenediamines such as n phenyl n 39 n dimethyl p phenylene diamine n phenyl n 39 n 39 diethyl p phenylenediamine n phenyl n 39 n 39 di n butyl.