In an embodiment, a polycarbonate polymerization process comprises interfacially polymerizing a carbonate compound and dihydroxy compound in the presence of an interfacial catalyst to form a polycarbonate and adding a viscosity reducing agent and a transesterification catalyst to polycarbonate upstream of a first filter to form an adjusted polycarbonate. The first filter can be replaced with a replacement filter and the adjusted polycarbonate can be introduced to the replacement filter. The flow can be diverted to a replacement filter. The process further comprises reducing the addition rate of the viscosity reducing agent and the transesterification catalyst until the addition rate is 0 mol/hr.

The present disclosure provides a copolymer comprising monomer units represented by formulas (I) and/or (II) as disclosed and defined herein which are useful in antibacterial and/or antifouling coatings. The present disclosure further provides methods of synthesizing said copolymers.

The present disclosure provides a copolymer comprising monomer units represented by formulas (I) and/or (II) as disclosed and defined herein which are useful in antibacterial and/or antifouling coatings. The present disclosure further provides methods of synthesizing said copolymers.

Disclosed herein are embodiments of a method for making recyclable polymers and a method for decomposing the polymers back to the monomers which can then be reused. The polymer are stable to aqueous and/or acid conditions and may have a formula II

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The method to decompose the polymer back to the monomers may comprise heating the polymer in a protic organic solvent.

A polycarbonate resin composition, a molded article, a polycarbonate resin, and an end-capping agent for polycarbonate resins are provided. The polycarbonate resin composition contains: a polycarbonate resin having a terminal structure represented by Formula (A) and having a viscosity average molecular weight from 1×10.sup.4 to 5×10.sup.4, and a stabilizer. In Formula (A), R.sup.1 is selected from the group consisting of a hydrogen atom, halogen atoms, linear alkyl groups having from 1 to 9 carbons, branched alkyl groups having from 3 to 9 carbons, linear alkenyl groups having from 2 to 9 carbons, branched alkenyl groups having from 3 to 9 carbons, and aryl groups having from 6 to 12 carbons; and R.sup.2 to R.sup.7 are each independently selected from the group consisting of a hydrogen atom, alkyl groups having from 1 to 9 carbons, and alkoxy groups having from 1 to 9 carbons. ##STR00001##

A polycarbonate resin composition, a molded article, a polycarbonate resin, and an end-capping agent for polycarbonate resins are provided. The polycarbonate resin composition contains: a polycarbonate resin having a terminal structure represented by Formula (A) and having a viscosity average molecular weight from 1×10.sup.4 to 5×10.sup.4, and a stabilizer. In Formula (A), R.sup.1 is selected from the group consisting of a hydrogen atom, halogen atoms, linear alkyl groups having from 1 to 9 carbons, branched alkyl groups having from 3 to 9 carbons, linear alkenyl groups having from 2 to 9 carbons, branched alkenyl groups having from 3 to 9 carbons, and aryl groups having from 6 to 12 carbons; and R.sup.2 to R.sup.7 are each independently selected from the group consisting of a hydrogen atom, alkyl groups having from 1 to 9 carbons, and alkoxy groups having from 1 to 9 carbons. ##STR00001##

Ways of preparing a partially crystalline polycarbonate powder are provided that include dissolving an amorphous polycarbonate in a polar aprotic solvent to form a first solution of solubilized polycarbonate at a first temperature. The first solution is then cooled to a second temperature, the second temperature being lower than the first temperature, where a portion of the solubilized polycarbonate precipitates from the first solution to form a second solution including the partially crystalline polycarbonate powder. Certain partially crystalline polycarbonate powders resulting from such methods are particularly useful in additive manufacturing processes, including powder bed fusion processes.

Ways of preparing a partially crystalline polycarbonate powder are provided that include dissolving an amorphous polycarbonate in a polar aprotic solvent to form a first solution of solubilized polycarbonate at a first temperature. The first solution is then cooled to a second temperature, the second temperature being lower than the first temperature, where a portion of the solubilized polycarbonate precipitates from the first solution to form a second solution including the partially crystalline polycarbonate powder. Certain partially crystalline polycarbonate powders resulting from such methods are particularly useful in additive manufacturing processes, including powder bed fusion processes.

A method for quenching a polymerisation process is described. The reaction of carbon dioxide with an epoxide in the presence of a bimetallic metal complex catalyst to produce a polymer comprises the quenching step of deactivation of the catalyst by contacting the catalyst with an acid effective to deactivate the catalyst. The deactivated catalyst may be removed from the polymer product by contacting the catalyst and polymer product with a solid phase and/or by precipitation; and the catalyst may also be optionally reactivated by contacting the deactivated catalyst with an anion. The acid may contain an anion effective to initiate the polymerisation process and effective to deactivate the catalyst and the molar ratio of acid to catalyst in the deactivation step may be less than or equal to 20:1 of the acid to catalyst mole ratio for the reaction.

A flame retardant with which fire retardancy is improved and the fire retardancy is able to be secured stably for a long time is provided. An internal layer 11 containing a polymer and a flame retardant factor layer 12 that is formed outside of the internal layer 11 and that contains a polymer to which at least one of a sulfonate group and a sulfonate base is bonded are included. Thereby, compared to a case that the flame retardant factor layer 12 is not included, moisture is hardly absorbed, and respective particles of the flame retardant are inhibited from being adhered to each other. Accordingly, blocking is inhibited.