In a process for producing a polymer blend, at least one first monomer is polymerized in a first slurry phase reaction zone in the presence of a supported first catalyst to produce a thermoplastic first polymer having a crystallinity of at least 30%. At least part of said first polymer is then contacted with at least one second monomer different from said first monomer in a second solution phase reaction zone in the presence of a second catalyst and in the absence of polyenes under conditions to produce a second polymer having a crystallinity of less than 20%.