Air-curable ethylene/alpha-olefin/diene interpolymer composition

A composition comprising:

• a reaction product of
• (A) from 96 wt % to 98 wt % of a crosslinkable polymer consisting of an ethylene/propylene/5-ethylidene-2-norbornene interpolymer, the ethylene/propylene/5-ethylidene-2-norbornene interpolymer with from 60 wt % to 80 wt % of ethylene, based on the total weight of the ethylene/propylene/5-ethylidene-2-norbornene interpolymer, 10 wt % to 35 wt % of propylene, based on the total weight of the ethylene/propylene/5-ethylidene-2-norbornene interpolymer, and from greater than 3 wt % to 7 wt % of 5 ethylidene-2-norbornene, based on the total weight of the ethylene/propylene/5-ethylidene-2-norbornene interpolymer, wherein the ethylene, the propylene, and the 5-ethylidene-2-norbornene amount to 100 wt % of the crosslinkable polymer;
• (B) from 1.25 wt % to 1.48 wt % of a peroxide comprising at least one —O—O— peroxide bond, based on the total weight of the composition;
• (C) from 0.25 wt % to 2.0 wt % of piperidinoxy,4-hydroxy-2,2,6,6-tetramethyl sebacate compound having Structure I, based on the total weight of the composition:
• wherein the ratio of the molar amount of nitroxide (NO·) groups of the component (C) to the molar amount of the peroxide bonds of the component (B) is from 0.180:1.000 to 0.900:1.000;
• wherein the (A), the (B), and the (C) amount to 100 wt % of the composition, the reaction product is crosslinked and has a degradation degree from greater than 0.000 to 0.200, a difference between maximum torque MH and minimum torque (MH-ML) of from 15.50 dNm to 17.00 dNm, an FTIR-ATR degradation H1460 from 190 to 205, and a FTIR-ATR degradation H1714 value from less than or equal to 20 to greater than 0.