N-Di-6efa-naphthyl-p-phenylene Diamine DNPD

DNPD is a member of the p-phenylenediamine family of AOs however, it is used more as an effective antioxidant and copper inhibitor (to prevent copper from degrading the cured rubber compound) than it is as an antiozonant (which is how most p-phenylenediamines are used). One to two parts per hundred rubber (phr) of DNPD will impart good heat and oxidative aging resistance with many different types of rubber. DNPD is relatively low staining compared to many other amine AOs. But DNPD can cause some discoloration with bright light exposure. 

ASTM D4676 classifies DNPD in relation to other antidegradants. 

DNPD is used as an effective, reiatively nonstaining AO and a copper scavenger to proiong the service iife of many rubber compounds based on a wide range of different raw eiastomers. 

DNPD is also used as an intermediate for organic synthesis and as a polymerization inhibitor for some processes. 

Other antioxidants may be substituted for DNPD but will impart different cured physical properties and oxidative protection characteristics that must be evaluated on a case-by-case basis. 

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