A process for the manufacture of a functionalized ethylene and propylene copolymer composition comprising the steps of: a) copolymerizing ethylene, propylene and at least one masked functionalized olefin monomer in the presence of a catalyst system, wherein the masked functionalized olefin monomer is a reaction product of a functionalized olefin monomer represented by the structure according to Formula and a masking agent: wherein R 2, R 3, and R 4 are each independently selected from the group consisting of H and hydrocarbyl with 1 to 16 carbon atoms, wherein R 5 -[X-(R 6) n] m is a polar functional group containing one or multiple heteroatom containing functionalities X-(R 6) n wherein X is selected from -O-, -S- or -CO 2 - and R 6 is H, and n is 1, or X is N and R 6 is each independently selected from the group consisting of H and a hydrocarbyl group with 1 to 16 carbon atoms, and n is 2, wherein R 5 is either -C(R 7a)(R 7b)- or a plurality of -C(R 7a)(R 7b)- groups, wherein R 7a, and R 7b are each independently selected from the group consisting of H or hydrocarbyl with 1 to 16 carbon atoms and R 5 comprises 1 to 10 carbon atoms, wherein R 3 and R 5 may together form a ring structure that is functionalized with one or multiple X-(R 6) n, where X is attached to either the main chain or side chain of R 5, where m is an entire number between 1 and 10, preferably 1 or 2, and b) treating the product obtained by step a) with a Bronsted acid solution, optionally containing metal salts or ammonium salts, capable to abstract the residue derived from the masking agent and combining the obtained functionalized ethylene and propylene copolymer with a cross-linking enhancing agent selected from the group consisting of polyols, polyamines, polyacids, polyethers, polyesters, polycarbonates, polyamides, polyurethanes, polyureas, polysaccharides, polypeptides and combinations of at least two of said cross-linking enhancing agents, wherein said cross-linking enhancing agent has at least two functionalities and the amount of cross-linking enhancing agent is from 0.01 to 10 wt.%, preferably from 0.03 to 7 wt.%, more preferably from 0.05 to 5 wt.%, based on the combined weight of the a functionalized ethylene and propylene copolymer and the cross-linking enhancing agent.. a) copolymerizing ethylene, propylene and at least one masked functionalized olefin monomer in the presence of a catalyst system, wherein the masked functionalized olefin monomer is a reaction product of a functionalized olefin monomer represented by the structure according to Formula and a masking agent: wherein R 2, R 3, and R 4 are each independently selected from the group consisting of H and hydrocarbyl with 1 to 16 carbon atoms, wherein R 5 -[X-(R 6) n] m is a polar functional group containing one or multiple heteroatom containing functionalities X-(R 6) n wherein X is selected from -O-, -S- or -CO 2 - and R 6 is H, and n is 1, or X is N and R 6 is each independently selected from the group consisting of H and a hydrocarbyl group with 1 to 16 carbon atoms, and n is 2, wherein R 5 is either -C(R 7a)(R 7b)- or a plurality of -C(R 7a)(R 7b)- groups, wherein R 7a, and R 7b are each independently selected from the group consisting of H or hydrocarbyl with 1 to 16 carbon atoms and R 5 comprises 1 to 10 carbon atoms, wherein R 3 and R 5 may together form a ring structure that is functionalized with one or multiple X-(R 6) n, where X is attached to either the main chain or side chain of R 5, where m is an entire number between 1 and 10, preferably 1 or 2, and wherein the masked functionalized olefin monomer is a reaction product of a functionalized olefin monomer represented by the structure according to Formula and a masking agent: wherein R 2, R 3, and R 4 are each independently selected from the group consisting of H and hydrocarbyl with 1 to 16 carbon atoms, wherein R 5 -[X-(R 6) n] m is a polar functional group containing one or multiple heteroatom containing functionalities X-(R 6) n wherein X is selected from -O-, -S- or -CO 2 - and R 6 is H, and n is 1, or X is N and R 6 is each independently selected from the group consisting of H and a hydrocarbyl group with 1 to 16 carbon atoms, and n is 2, wherein R 5 is either -C(R 7a)(R 7b)- or a plurality of -C(R 7a)(R 7b)- groups, wherein R 7a, and R 7b are each independently selected from the group consisting of H or hydrocarbyl with 1 to 16 carbon atoms and R 5 comprises 1 to 10 carbon atoms, wherein R 3 and R 5 may together form a ring structure that is functionalized with one or multiple X-(R 6) n, where X is attached to either the main chain or side chain of R 5, where m is an entire number between 1 and 10, preferably 1 or 2, and b) treating the product obtained by step a) with a Bronsted acid solution, optionally containing metal salts or ammonium salts, capable to abstract the residue derived from the masking agent and combining the obtained functionalized ethylene and propylene copolymer with a cross-linking enhancing agent selected from the group consisting of polyols, polyamines, polyacids, polyethers, polyesters, polycarbonates, polyamides, polyurethanes, polyureas, polysaccharides, polypeptides and combinations of at least two of said cross-linking enhancing agents, wherein said cross-linking enhancing agent has at least two functionalities and the amount of cross-linking enhancing agent is from 0.01 to 10 wt.%, preferably from 0.03 to 7 wt.%, more preferably from 0.05 to 5 wt.%, based on the combined weight of the a functionalized ethylene and propylene copolymer and the cross-linking enhancing agent..