An in-line blending process for polymers comprising: (a) providing two or more reactor-low pressure separator units (1,7) in parallel configuration, each reactor-low pressure separator unit comprising one reactor (2,8) fluidly connected to one low pressure separator (3,9) downstream and further a recycling line (5,11) connecting the low pressure separator (3,9) back to the corresponding reactor (2,8); (b) polymerizing olefin monomers having two or more carbon atoms in each of the reactors (2,8) in solution polymerisation; (c) forming an unreduced reactor effluents stream including a homogenous fluid phase polymer-monomer-solvent mixture in each of the reactors (2,8), (d) passing the unreduced reactor effluents streams from each of the reactors (2,8) through the corresponding low pressure separators (3,9), whereby the temperature and pressure of the low pressure separators (3,9) is adjusted such that a liquid phase and a vapour phase are obtained, whereby yielding a polymer-enriched liquid phase and a polymer-lean vapour phase, and (e) separating the polymer-lean vapour phase from the polymer-enriched liquid phase in each of the low-pressure separators (3,9) to form separated polymer-lean vapour streams and separated polymer-enriched liquid streams; (f) combining the polymer-enriched liquid streams from step (e) in a further low-pressure separator and/or a mixer (13) to produce a combined polymer-enriched liquid stream (16); (g) reintroducing the polymer-lean vapour streams from step (e) via recycling lines (5,11) into the corresponding reactors (2,8).

The present invention relates to a method for recovering ethylene and a vinyl-comonomer that is capable of improving the rate of recovery of unreacted monomers remaining after polymerization of ethylene and a vinyl-based comonomer and increasing process efficiency through the reduction of costs. Specifically, the method for recovering ethylene and a vinyl-comonomer includes: a step of polymerizing ethylene and a vinyl-based comonomer at a pressure of 1500 bar or more; a step of depressurizing the product obtained in the polymerization step including an ethylene-vinyl-based comonomer polymer, ethylene, and a vinyl-based comonomer to 0.1 bar to 5 bar; a step of adding ethylene to the product obtained in the polymerization step under the pressure of 0.1 bar to 5 bar; and a step of separating ethylene and a vinyl-based comonomer from the product obtained in the polymerization step to which the ethylene is added.

The present invention relates to a method for recovering ethylene and a vinyl-comonomer that is capable of improving the rate of recovery of unreacted monomers remaining after polymerization of ethylene and a vinyl-based comonomer and increasing process efficiency through the reduction of costs. Specifically, the method for recovering ethylene and a vinyl-comonomer includes: a step of polymerizing ethylene and a vinyl-based comonomer at a pressure of 1500 bar or more; a step of depressurizing the product obtained in the polymerization step including an ethylene-vinyl-based comonomer polymer, ethylene, and a vinyl-based comonomer to 0.1 bar to 5 bar; a step of adding ethylene to the product obtained in the polymerization step under the pressure of 0.1 bar to 5 bar; and a step of separating ethylene and a vinyl-based comonomer from the product obtained in the polymerization step to which the ethylene is added.

A process for reducing the volatile organic compound content of granular plastomers having a density of equal to or lower than 883 kg/m.sup.3 and a MFR.sub.2 of 100.0 g/10 min or lower (ISO 1133 at 2.16 kg load and 190 C.), to below 65 ppm (VOC, VDA277), the process comprising the steps of providing a granular raw plastomer in a treatment vessel, the granular raw plastomer having a density of equal to or lower than 883 kg/m.sup.3, and a MFR.sub.2 of 100.0 g/10 min or lower (ISO 1133 at 2.16 kg load and 190 C.), and a volatile organic compound content (VOC, VDA277) of above 150 ppm, subjecting said granular raw plastomer to a gasflow within the range of 30 m.sup.3/(h t) to 150 m.sup.3/(h t) for an aeration time of less than 96 hours, whereby the gas has a minimum temperature of at least 26 C. measured at a gas inlet of the treatment vessel and a maximum temperature of 4 C. below the Vicat temperature (10 N, ISO 306) of the granular raw plastomer or 35 C. measured at the gas inlet of the treatment vessel, whatever value is lower; and recovering the granular plastomer.

A process for producing cycloalkenamer-containing compositions involves converting at least one cycloalkene by ring-opening metathetic polymerization to obtain a polyalkenamer-containing product mixture. The product mixture is worked up to remove monomers and oligomers of the cycloalkenes to obtain the polyalkenamer-containing composition by extraction with CO.sub.2. The extraction involves at least two stages: an extraction with liquid CO.sub.2 under the supercritical conditions, and then an extraction with supercritical CO.sub.2. Such cycloalkenamer-containing compositions can be used, for example, in the field of packaging materials, especially for food and drink.

A process for producing cycloalkenamer-containing compositions involves converting at least one cycloalkene by ring-opening metathetic polymerization to obtain a polyalkenamer-containing product mixture. The product mixture is worked up to remove monomers and oligomers of the cycloalkenes to obtain the polyalkenamer-containing composition by extraction with CO.sub.2. The extraction involves at least two stages: an extraction with liquid CO.sub.2 under the supercritical conditions, and then an extraction with supercritical CO.sub.2. Such cycloalkenamer-containing compositions can be used, for example, in the field of packaging materials, especially for food and drink.

Disclosed are a system for controlling an ethylene vinyl acetate (EVA) copolymerization process and a method of controlling the same. The system for controlling the EVA copolymerization process may include a database for analysis configured to store analysis data obtained by matching processing conditions with measured data for first EVAs produced under the processing conditions, a vinyl acetate (VA) content estimation unit configured to estimate a VA content with respect to second EVA using the analysis data, a molecular weight distribution estimation unit configured to estimate a molecular weight distribution of the second EVA using the VA content estimated in the VA content estimation unit and processing factors corresponding thereto, and a recovery system blockage estimation unit configured to estimate a recovery system blockage phenomenon using the VA content estimated in the VA content estimation unit and the molecular weight distribution estimated in the molecular weight distribution estimation unit.

Disclosed are a system for controlling an ethylene vinyl acetate (EVA) copolymerization process and a method of controlling the same. The system for controlling the EVA copolymerization process may include a database for analysis configured to store analysis data obtained by matching processing conditions with measured data for first EVAs produced under the processing conditions, a vinyl acetate (VA) content estimation unit configured to estimate a VA content with respect to second EVA using the analysis data, a molecular weight distribution estimation unit configured to estimate a molecular weight distribution of the second EVA using the VA content estimated in the VA content estimation unit and processing factors corresponding thereto, and a recovery system blockage estimation unit configured to estimate a recovery system blockage phenomenon using the VA content estimated in the VA content estimation unit and the molecular weight distribution estimated in the molecular weight distribution estimation unit.

The present invention relates to a process for producing cycloalkenamer-containing compositions, comprising the steps of: a) converting at least one cycloalkene by ring-opening metathetic polymerization to obtain a polyalkenamer-containing product mixture, and b) working up the product mixture to remove monomers and oligomers of the cycloalkenes to obtain the polyalkenamer-containing composition by extraction with CO.sub.2, whereby the polyalkenamers are polymers of cycloalkenes which comprise at least five cycloalkane monomer units, wherein the extraction comprises at least two stages: b0) an extraction with liquid CO.sub.2, then b1) an extraction with supercritical CO.sub.2, then b2) an extraction with gaseous CO.sub.2, then b0) an extraction with liquid CO.sub.2, then and then b3) an extraction with supercritical CO.sub.2.

An eductor, a process and apparatus for gas phase polymerization of olefins in a polymerization reactor are disclosed. The process and apparatus employ an eductor which has an inlet which makes a bend of less than about 90 toward the outlet after entering the mixing chamber of the eductor.