摘要:
The present invention discloses new catalyst systems based on complexes of divalent metals supported by chelating phenoxy ligands for immortal ring-opening polymerisation of cyclic esters and cyclic carbonates.
摘要:
The present invention discloses new catalyst systems based on complexes of divalent metals supported by chelating phenoxy ligands for immortal ring-opening polymerisation of cyclic esters and cyclic carbonates.
摘要:
A polymer production apparatus, including: supplying unit containing first supplying unit to supply raw materials containing monomer, and second supplying unit to supply compressive fluid; contacting unit to bring the monomer and the compressive fluid into contact together; and outlet configured to discharge reaction product of the monomer, wherein reaction unit is provided between the contacting unit and the outlet, where the reaction unit is to pass the monomer from the contacting unit side to the outlet side, while allowing the monomer to carry out a polymerization reaction in the presence of the compressive fluid, and wherein the reaction unit contains circulation unit containing first pipe and second pipe, where a fluid is passed through the first pipe from the contacting unit side to the outlet side, and the second pipe is to return the fluid from return port provided upstream extrusion unit to inlet provided upstream the return port.
摘要:
A high molecular weight polycarbonate resin is continuously produced by subjecting an aromatic polycarbonate prepolymer and an aliphatic diol compound to a linking and highly polymerizing reaction. Even an aliphatic diol compound having a comparatively low boiling point can be allowed to efficiently contribute to the linking and highly polymerizing reaction. An aromatic polycarbonate prepolymer is produced by a polycondensation reaction between an aromatic dihydroxy compound and a diester carbonate, adding an aliphatic diol compound having an aliphatic group bonding to a terminal hydroxyl group to obtain a prepolymer mixture, and subjecting the resulting prepolymer mixture to a linking and highly polymerizing reaction under reduced pressure. The aliphatic diol compound is added at a pressure exceeding 200 torr, and the prepolymer mixture is subjected to a linking and highly polymerizing reaction before the terminal hydroxyl group concentration of the aromatic polycarbonate prepolymer in the prepolymer mixture reaches 2000 ppm.
摘要:
A branched aromatic polycarbonate resin having a degree of branching (N value) controlled within a specific range is manufactured by subjecting an aromatic polycarbonate prepolymer that has a branched structure introduced using a specific amount of a branching agent to molecular-weight-increasing linking reaction with an aliphatic diol compound in the presence of a transesterification catalyst under the condition of a reduced pressure. The amount (A) of the branching agent used is adjusted on the basis of the correlation between the amount (A) of the branching agent used and the N value of the branched aromatic polycarbonate resin.
摘要:
This invention relates to a method of fixing carbon dioxide by condensation polymerization in an acidic aqueous medium, thereby increasing fixation efficiency and remarkably reducing the volume of generated material compared to conventional carbon dioxide fixation methods; a polymer material prepared by the method; and a method of recovering carbon therefrom. According to the current invention, the method of fixing carbon dioxide is characterized by introducing carbon dioxide pressurized to a pressure higher than atmospheric pressure into a reactor containing a acidic aqueous medium, so that carbonic acid resulting from dissolving carbon dioxide is made into a polymer material by condensation polymerization, thereby fixing carbon dioxide, and heating the polymer material so as to recover carbon.
摘要:
To provide a method for producing a polymer, which contains: bringing a compressive fluid and a ring-opening polymerizable monomer into contact with each other, followed by adding a catalyst thereto, to thereby allow the ring-opening polymerizable monomer to carry out ring-opening polymerization.
摘要:
[Problem] To provide a process for manufacturing, easily and using a conventional branching agent, a branched aromatic polycarbonate resin which has both a sufficiently high molecular weight and a desired degree of branching. [Solution] A branched aromatic polycarbonate resin having a degree of branching (N value) controlled within a specific range is manufactured by subjecting an aromatic polycarbonate prepolymer that has a branched structure introduced using a specific amount of a branching agent to molecular-weight-increasing linking reaction with an aliphatic diol compound in the presence of a transesterification catalyst under the condition of a reduced pressure. The amount (A) of the branching agent used in adjusted on the basis of the correlation between the amount (A) of the branching agent used and the N value of the branched aromatic polycarbonate resin.
摘要:
A subject for the invention is to provide a polycarbonate having excellent mechanical strength, heat resistance, a low refractive index, a large Abbe number, reduced birefringence, and excellent transparency. The invention relates to a polycarbonate characterized by being obtained by subjecting one or more dihydroxy compounds including a dihydroxy compound having at least one linking group —CH2—O— in the molecule thereof to melt polycondensation with a carbonic acid diester, and by having a reduced viscosity of from 0.40 dL/g to 1.70 dL/g and a formic acid content lower than 5 ppm by weight.
摘要:
Biodegradable cationic block copolymers are disclosed, comprising a hydrophilic block comprising first repeat units derived from a first cyclic carbonyl monomer by ring-opening polymerization, wherein more than 0% of the first repeat units comprise a side chain moiety comprising a quaternary amine group; a hydrophobic block comprising second repeat units derived from a second cyclic carbonyl monomer by ring-opening polymerization; an optional endcap group; and a chain fragment derived from an initiator for the ring opening polymerization. The cationic block copolymers form aqueous micelle mixtures suitable for antimicrobial applications.