Process for metallating nonconjugated diene-containing ethylene polymers and graft polymers prepared therefrom

A process for preparing a graft polymer having an ethylene polymer backbone and a plurality of side chains, the process comprising:

• (a) metallating an ethylene polymer, said polymer having polymerized therein ethylene, a nonconjugated diene and at least one 1-olefin having three or more carbon atoms by a process which comprises:
• (1) providing an admixture of the ethylene polymer and a saturated, nonpolar, hydrocarbon solvent,
• (2) forming an intermixture of the admixture and activating amounts of a tertiary diamine and a potassium alkoxide, and
• (3) contacting the intermixture with an amount of at least one lithium alkyl compound under conditions sufficient to provide more than about twenty percent of the polymer molecules with at least one lithiated site, the amounts of the tertiary diamine, the potassium alkoxide and the lithium alkyl also being sufficient to provide a degree of metallation greater than the degree of metallation attained with (i) the potassium alkoxide and the lithium alkyl compound or (ii) the tertiary diamine and the lithium alkyl compound, or by adding the degrees of metallation attained with (i) and (ii);
• and
• (b) contacting the metallated ethylene polymer with a reagent selected from the group consisting of compounds having sufficient electrophilic character to react with the metallated ethylene polymer which is nucleophilic.