Patent ID: 11136419

Abstract:
A high pressure, free radical polymerization process to form an ethylene-based polymer, the process comprising at least the following step: polymerizing a reaction mixture comprising ethylene, using a polymerization system comprising the following: (A) a reactor configuration comprising at least one reactor that comprises at least two reaction zones, a first reaction zone (reaction zone 1) and an ith reaction zone (where i≥2); wherein the ith reaction zone is the last reaction zone, and wherein i is the total number of reaction zones; (B) at least two ethylene-based feed streams, a first ethylene-based feed stream and an nth ethylene-based feed stream, wherein the first ethylene-based feed stream is sent to the first reaction zone, and the nth ethylene-based feed stream is the last ethylene based feed stream sent to the reactor configuration; wherein n≤i; and RZn/RZ1 does not equal 1.0, where RZ1=mole fraction of make-up ethylene in the first ethylene-based feed stream to the first reaction zone; where RZn=mole fraction of make-up ethylene in the last ethylene-based feed stream sent to the reactor configuration; (C) a control system to control the percentage of the make-up ethylene in the first ethylene-based feed stream, and the percentage of the make-up ethylene in the nth ethylene-based feed stream; and wherein at least one reaction zone receives a CTA make-up feed stream comprising an alpha-olefin, and wherein the alpha-olefin has a chain transfer activity constant (Cs) value ≤0.10, and wherein the chain transfer activity constant (Cs) is measured at 1360 atm, 130° C.