The invention relates to an efficient polymerization process and its use to produce novel copolymers with a specific microstructure. In particular, the invention relates to butyl rubbers with novel microstructure, preferably those obtainable by copolymerization of monomer mixtures comprising isobutylene and isoprene. In a further aspect the invention relates to halogenated copolymers obtainable from such novel copolymers by halogenation.

Process for purification of unreacted vinyl acetate monomers comprising the steps of preliminarily loading an adsorbent agent bed with a mixture comprising an inert gas and fresh vinyl acetate; and feeding said adsorbent agent bed with unreacted vinyl acetate monomers to remove acetic acid.

Process for purification of unreacted vinyl acetate monomers comprising the steps of preliminarily loading an adsorbent agent bed with a mixture comprising an inert gas and fresh vinyl acetate; and feeding said adsorbent agent bed with unreacted vinyl acetate monomers to remove acetic acid.

Process for purification of unreacted vinyl acetate monomers comprising the steps of preliminarily loading an adsorbent agent bed with a mixture comprising an inert gas and fresh vinyl acetate; and feeding said adsorbent agent bed with unreacted vinyl acetate monomers to remove acetic acid.

To provide a process for producing a fluorinated polymer having a cyclic structure at a relatively low cost, by efficiently recovering, from a mixture containing a fluorinated polymer obtained by polymerizing a perfluoromonomer having a cyclic structure and an unreacted perfluoromonomer having a cyclic structure, the unreacted perfluoromonomer having a cyclic structure. A monomer component containing a perfluoromonomer having a specific cyclic structure is polymerized in the presence of a polymerization initiator at a predetermined polymerization temperature to obtain a mixture containing a fluorinated polymer and an unreacted cyclic structure monomer, and the perfluoromonomer having a cyclic structure is recovered from the mixture at a temperature of at most the maximum ultimate temperature of the polymerization temperature+12 C. and at most the 10 hour half-life temperature of the polymerization initiator+12 C. under a pressure of less than the atmospheric pressure.

A process for withdrawing polyolefins from a reactor includes: continuously withdrawing a liquid solution stream from a solution polymerization reactor and passing the liquid solution stream into a low pressure separator; withdrawing a first vapour stream and a first liquid stream from the separator and passing the first vapour stream into a washing column; withdrawing a second vapour stream from the washing column and feeding it via a condenser line to a condenser; cooling the second vapour stream in the condenser so that part of the second vapour stream condenses, producing a condensed second vapour stream and an uncondensed second vapour stream; passing the condensed second vapour stream to an upper part of the washing column via a reflux line; withdrawing a second liquid stream from the washing column and passing at least part of the second liquid stream to the separator via a recycling line; and recovering heat.

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.

Provided in one implementation is a method that includes introducing a volume of raw material into a chamber of a cavitation machine. The raw material can include a mixture comprising a powder and a solvent. The powder can have a first average particle size in the raw material. The method includes applying a hydrodynamic cavitation process to the raw material to produce a product material. The powder can have a second average particle size, smaller than the first average particle size, in the product material. The method includes causing the product material to exit the cavitation chamber and drying the product material to remove the solvent. Apparatus employed to apply the method are also provided.

Provided in one implementation is a method that includes introducing a volume of raw material into a chamber of a cavitation machine. The raw material can include a mixture comprising a powder and a solvent. The powder can have a first average particle size in the raw material. The method includes applying a hydrodynamic cavitation process to the raw material to produce a product material. The powder can have a second average particle size, smaller than the first average particle size, in the product material. The method includes causing the product material to exit the cavitation chamber and drying the product material to remove the solvent. Apparatus employed to apply the method are also provided.