Abstract:
A process to form an olefin-based polymer, said process comprising at least the following steps: a) polymerizing a reaction mixture comprising an olefin, in at least one reactor, in a solution polymerization, to form a polymer solution; b) feeding at least a portion of the polymer solution through at least one devolatilizer, to form the olefin-based polymer, in melt form; c) feeding at least a portion of the olefin-based polymer, in melt, form through a heat exchanger, and then into a pastillation apparatus to form polymer particles.
Abstract:
The instant invention provides an improved process for producing pelletized polymer compositions, and pelletized polymer compositions. The process for producing a pelletized polymer composition according to the present invention comprises: (1) polymerizing one or more alpha-olefins in one or more solution reactors thereby producing a molten polymer composition comprising one or more solvents; (2) removing at least a portion of said one or more solvents thereby forming a polymer composition having a low solvent content (typically less than 1,000 parts of solvent per million of polymer on a weight basis); (3) removing heat from said polymer composition having low solvent content to a temperature in the range of equal to or greater than the crystallization point of the polymer composition having low solvent content to less than or equal to a temperature in the range of from (the crystallization point of the polymer composition having low solvent content+20° C.) thereby forming a viscous polymer melt; and (4) pelletizing said viscous polymer melt via an underwater pelletizer thereby forming said pelletized polymer composition.
Abstract:
The invention provides a method, and apparatus, for determining the degree of separation (DOS) of a polymer solution into a polymer-rich stream and a solvent-rich stream, said method comprising the following: adding to a liquid-liquid separation vessel the polymer solution, which comprises a polymer, a solvent and an anti-solvent; separating the polymer solution into a polymer-rich stream and a solvent-rich stream; removing at least some the polymer-rich stream from at least one outlet P on the vessel, and measuring the actual solution density of this polymer-rich stream using at least one flow meter; removing at least some of the solvent-rich stream from at least one other outlet S on the vessel, and measuring the actual density of the solvent-rich stream using at least one flow meter; and wherein the degree of separation (DOS) is determined by the following equation (Eqn. 1): DOS=[actual solution density (polymer-rich steam)−actual solution density (solvent-rich stream)]/[theoretical solution density (polymer-rich stream)−theoretical solution density (solvent-rich stream)] (Eqn. 1).
Abstract:
The invention provides a process to form an ethylene-based polymer, said process comprising polymerizing ethylene in presence of at least the following: A) a free-radical agent; B) an alkylated phenol selected from Formula (I), wherein R1, R2,R3, R4 and R5 are each, independently, hydrogen or an alkyl; and C) a “metal alkyl-containing compound” selected from the group consisting of the following: i) at least one “Group II metal alkyl-containing compound,” ii) at least one “Group III metal alkyl-containing compound,” and iii) a combination of i) and ii).