Ethylene acid copolymers, their ionomers, and their use in packaging films and injection molded articles

A polymer composition comprising:

• an ethylene acid copolymer,
• a hydroxyl-containing crosslinking agent, and
• a silane adjuvant;
• said ethylene acid copolymer comprising copolymerized units of ethylene, about 10 wt % to about 30 wt % of copolymerized units of a first α,β-unsaturated carboxylic acid having 3 to 10 carbon atoms and about 5 wt % to about 15 wt % of copolymerized units of a derivative of a second α,β-unsaturated carboxylic acid having 3 to 10 carbon atoms;
• wherein the weight percentages of the copolymerized units are based on the total weight of the ethylene copolymer and the sum of the weight percentages of the copolymerized units is 100 wt %;
• wherein the hydroxyl-containing crosslinking agent is a diol selected from 1,4-butanediol, 1,3-propanediol, 1,6-hexanediol, or combinations thereof;
• and
• wherein at least a portion of the carboxylic acid groups of the first α,β-unsaturated carboxylic acid are neutralized to form an ionomer comprising carboxylate groups having counterions.