The invention relates to a process for the synthesis of a polymer bearing one or more pendant hydroxyaryl groups comprising the reaction of a polymer bearing one or more pendant epoxide functional groups with a nucleophilic compound bearing the hydroxyaryl group.

The invention relates to a process for the synthesis of a polymer bearing one or more pendant hydroxyaryl groups comprising the reaction of a polymer bearing one or more pendant epoxide functional groups with a nucleophilic compound bearing the hydroxyaryl group.

The present disclosure provides an additive and a method for terminating polymerization and/or reducing viscosity of polymer solution. The additive comprises a carboxylic acid, an alcohol, a salt chosen from alkali metal salts, alkaline earth metal salts, ammonium salts, and any combination thereof, and optionally, water. The method of the present disclosure comprises adding the additive according to present disclosure into a polymer solution and mixing the resulting mixture. The additive of the present disclosure can terminate living polymer chain ends efficiently and can destroy catalytic active centers and can substantially reduce the viscosity of a polymer solution.

The present disclosure provides an additive and a method for terminating polymerization and/or reducing viscosity of polymer solution. The additive comprises a carboxylic acid, an alcohol, a salt chosen from alkali metal salts, alkaline earth metal salts, ammonium salts, and any combination thereof, and optionally, water. The method of the present disclosure comprises adding the additive according to present disclosure into a polymer solution and mixing the resulting mixture. The additive of the present disclosure can terminate living polymer chain ends efficiently and can destroy catalytic active centers and can substantially reduce the viscosity of a polymer solution.

A method for the control of a plant (10) for the production in continuous of a polymer, wherein the plant (10) comprises at least one reactor (11) fed with at least a first monomer and a second monomer, a first stripper (12), a second stripper (17), a third stripper (18), at least one recycling vat (13) of the fine products, measurement equipment (14) and a control system comprising distributed control devices (15) controllable by at least one electronic processing and control unit (16) based on a plurality of control variables, the control method comprising the following steps: collecting data comprising recipe parameters, laboratory analysis results and predefined coefficients stored in a database (40); collecting the data measured by the measurement equipment (14); determining, by means of a first calculation module (20) a production potentiality value of the at least one reactor (11); determining, by means of a second calculation module (21) the polymer concentration in the at least one reactor (11), in the first stripper (12) and in the at least one recycling vat of the fine products (13); determining, by means of a third calculation module (22) the flow-rate of oil for feeding the second stripper (17); determining, by means of a fourth calculation module (23), the flow-rate of the chain terminator (TERM) for feeding the at least one reactor (11), controlling the plant (10) on the basis of the plurality of control variables.

A method for the control of a plant (10) for the production in continuous of a polymer, wherein the plant (10) comprises at least one reactor (11) fed with at least a first monomer and a second monomer, a first stripper (12), a second stripper (17), a third stripper (18), at least one recycling vat (13) of the fine products, measurement equipment (14) and a control system comprising distributed control devices (15) controllable by at least one electronic processing and control unit (16) based on a plurality of control variables, the control method comprising the following steps: collecting data comprising recipe parameters, laboratory analysis results and predefined coefficients stored in a database (40); collecting the data measured by the measurement equipment (14); determining, by means of a first calculation module (20) a production potentiality value of the at least one reactor (11); determining, by means of a second calculation module (21) the polymer concentration in the at least one reactor (11), in the first stripper (12) and in the at least one recycling vat of the fine products (13); determining, by means of a third calculation module (22) the flow-rate of oil for feeding the second stripper (17); determining, by means of a fourth calculation module (23), the flow-rate of the chain terminator (TERM) for feeding the at least one reactor (11), controlling the plant (10) on the basis of the plurality of control variables.

A solution polymerization process for producing ethylene-based polymer includes introducing ethylene monomer, hydrocarbon solvent, and Ziegler-Natta catalyst into an entrance of a solution polymerization reactor. An ethylene-based polymer is produced by solution polymerizing the ethylene monomer in hydrocarbon solvent. Subsequently, a catalyst deactivator is introduced into x the exit of the solution polymerization reactor, thereby producing hydrochloric acid byproduct. The catalyst deactivator includes long chain carboxylate and at least one cation selected from Groups 1, 2, and 12 of the IUPAC periodic table, with the exception of calcium. The catalyst deactivator reduces the effectiveness of the Ziegler-Natta catalyst and neutralizes the hydrochloric acid by forming a chloride salt other than calcium chloride.

A solution polymerization process for producing ethylene-based polymer includes introducing ethylene monomer, hydrocarbon solvent, and Ziegler-Natta catalyst into an entrance of a solution polymerization reactor. An ethylene-based polymer is produced by solution polymerizing the ethylene monomer in hydrocarbon solvent. Subsequently, a catalyst deactivator is introduced into x the exit of the solution polymerization reactor, thereby producing hydrochloric acid byproduct. The catalyst deactivator includes long chain carboxylate and at least one cation selected from Groups 1, 2, and 12 of the IUPAC periodic table, with the exception of calcium. The catalyst deactivator reduces the effectiveness of the Ziegler-Natta catalyst and neutralizes the hydrochloric acid by forming a chloride salt other than calcium chloride.

A catalyst system comprising a combination of: 1) one or more catalyst compounds comprising at least one nitrogen linkage; 2) a support comprising an organosilica material, which is a mesoporous organosilica material; and 3) an optional activator. Useful catalysts include pyridyldiamido transition metal complexes, HN5 compounds, and bis(imino)pyridyl complexes. The organosilica material is a polymer of at least one monomer of Formula [Z.sup.1OZ.sup.2SiCH.sub.2].sub.3(1), where Z.sup.1 represents a hydrogen atom, a C.sub.1-C.sub.4alkyl group, or a bond to a silicon atom of another monomer and Z.sup.2 represents a hydroxyl group, a C1-C.sub.4alkoxy group, a C.sub.1-C.sub.6 alkyl group, or an oxygen atom bonded to a silicon atom of another monomer. This invention further relates to processes to polymerize olefins comprising contacting one or more olefins with the above catalyst system.

Provided is a method for producing a polyvinyl alcohol having improved mechanical strength without significantly impairing productivity. A method for producing a polyvinyl alcohol having an average degree of polymerization of 5.0×10.sup.3 or more and 1.5×10.sup.4 or less, the method including steps of: subjecting a vinyl ester-based monomer to suspension polymerization at a polymerization temperature of 10° C. or more and 50° C. or less with a polymerization rate of 10% or more and 70% or less to obtain a vinyl ester-based polymer; dissolving the vinyl ester-based polymer in an alcohol-based solvent; and carrying out a saponification reaction by adding a saponification catalyst to an alcohol-based solution of the dissolved vinyl ester-based polymer.