A process for the production of a propylene based
polymer, the process comprising the following steps: (a) a first
polymerization stage comprising homopolymerizing propylene or copolymerizing propylene and at least one alpha-olefin in the presence of an alpha-
olefin polymerization catalyst whereby to produce a
polypropylene component; (b) a second
polymerization stage comprising copolymerizing
ethylene and at least one alpha-olefin in the presence of an alpha-
olefin polymerization catalyst whereby to produce an
ethylene / alpha-olefin
copolymer component; and (c) blending the
polymer components produced in steps (a) and (b) whereby to produce a
polymer blend, wherein the first and second
polymerization stages are effected in separate polymerization reactors connected in parallel. Also provided are polymer compositions comprising: (i) 30 to 97% by weight, based on the total weight of the
polymer composition, of a propylene based polymer; and (ii) 3 to 70% by weight, preferably 5 to 20% by weight, based on the total weight of the
polymer composition, of an
ethylene copolymer plastomer (e.g., an ethylene-propylene
plastomer) containing at least 60% by weight ethylene.