Method for modifying polycarbonate with siloxane

Abstract

The present application discloses a method comprising contacting one or more reactive polycarbonates having free hydroxyl and / or carboxyl groups with one or more reactive siloxane compounds terminated with one or more acetoxy, methoxy, ethoxy, halide, hydrogen atoms in a solvent system, the one or more reactive polycarbonates are coupled to the recovery solution to form one or more siloxane-modified polycarbonates in the recovery solution, and the one or more reactive polycarbonates comprise one or more waste polycarbonates.

Description

Technical Field

[0001] A method is disclosed for chemically modifying recycled polycarbonate to give the polycarbonate improved molecular weight, flame retardancy, and / or reduced hydroxyl and / or carboxyl groups in the polymer composition. Background Technology

[0002] Polycarbonate and its copolymers containing carbonate units are used in a variety of molded structures. These molded structures are used for a wide range of applications, including housings for electronics, automotive parts, medical devices, home appliances, speakers, household goods, and more. Over time, polycarbonate and its copolymers can degrade. Degraded polycarbonate tends to accumulate in waste materials. Because the degradation of polycarbonate and its copolymers introduces undesirable side effects, such as the introduction of unwanted derivative monomers and reduced properties due to molecular weight loss, measures are needed to absorb and recycle polycarbonate.

[0003] Therefore, what is needed is a technology to modify recycled polycarbonate so that the polycarbonate has properties that can be used in new consumer products. Summary of the Invention

[0004] This application discloses a method comprising contacting one or more reactive polycarbonates having free hydroxyl and / or carboxyl groups with one or more reactive siloxane compounds terminated with one or more acetoxy, methoxy, ethoxy, halide, or hydrogen atoms in a solvent system to form one or more siloxane-modified polycarbonates in a recycled solution, wherein the one or more reactive polycarbonates comprise one or more waste polycarbonates.

[0005] One or more reactive polycarbonates may comprise one or more waste polycarbonates in an amount from about 5% to about 95% by weight, based on the total amount of reactive polycarbonates. Free hydroxyl and / or carboxyl groups may be positioned at one or more ends of the reactive polycarbonate. Free hydroxyl and / or carboxyl groups may be positioned along the backbone of the reactive polycarbonate. Siloxane-modified polycarbonates may have a number-average and / or weight-average molecular weight at least 5% greater than that of the reactive polycarbonates incorporated into the siloxane-modified polycarbonate. The method may further include contacting a solvent system with one or more waste feedstocks comprising one or more waste polycarbonates and one or more non-polycarbonate compounds to form a recovery solution; and separating at least some of the one or more non-polycarbonate compounds from the recovery solution. The method may further include contacting one or more precursor siloxane compounds with water to form one or more reactive siloxane compounds in the recovery solution; and contacting the recovery solution with one or more polycarbonate solvents to form a solvent system comprising the water and the one or more polycarbonate solvents in the recovery solution. The method may further include contacting one or more reactive polycarbonates with one or more allyl halides to form one or more vinyl ether-terminated polycarbonates, said vinyl ether-terminated polycarbonates being configured to react with hydrogen atoms of one or more reactive siloxane compounds to form one or more siloxane-modified polycarbonates. The one or more allyl halides may be terminated with an olefin and a halide, and may contain 1 to 100 carbon atoms between the carbon atoms at the halide and the olefin. The method may include contacting one or more scavengers with a recovery solution to remove acid formed by contacting one or more reactive polycarbonates with one or more reactive siloxane compounds. The reactive polycarbonates and reactive siloxane compounds may be contacted in the presence of a catalyst configured to promote the formation of siloxane-modified polycarbonates. The solvent system may contain at least a polycarbonate solvent configured to dissolve one or more reactive polycarbonates, and optionally may also include water. One or more reactive siloxane compounds may comprise 1 to 100 siloxane units linked in a chain, said chain being capped with at least one hydrogen, acetoxy, methoxy, ethoxy, halide group or any combination thereof.

[0006] This disclosure provides a polymerizable composition comprising one or more reactive polycarbonates having free hydroxyl and / or carboxyl groups along the backbone of the one or more reactive polycarbonates and / or at one or more ends of the one or more reactive polycarbonates, wherein the one or more reactive polycarbonates comprise one or more waste polycarbonates. The polymerizable composition comprises a solvent system containing one or more polycarbonate solvents and / or water. The polymerizable composition comprises one or more siloxane modifiers, the one or more siloxane modifiers comprising at least one of the following: one or more reactive siloxane compounds terminated with at least one hydrogen and one or more allyl halides; one or more reactive siloxane compounds terminated with at least one acetoxy, methoxy, ethoxy, halide, or any combination thereof; or one or more precursor siloxane compounds configured to form a reactive siloxane compound terminated with at least one halide in water. One or more reactive polycarbonates and siloxane modifiers can react in a solvent system to form one or more siloxane-modified polycarbonates.

[0007] This disclosure provides a polymer composition comprising one or more siloxane-modified polycarbonates. The siloxane-modified polycarbonate comprises one or more polycarbonate segments and one or more siloxane segments, the one or more siloxane segments being linked to the one or more polycarbonate segments along the main chain at oxygen atoms and at the ends of the one or more polycarbonate segments. At least some of the one or more siloxane segments are linked to two or more polycarbonate segments.

[0008] One or more polycarbonate segments may contain at least about 5% to 100% or more residues of waste polycarbonate based on the total amount of siloxane-modified polycarbonate. Each of the one or more siloxane segments may contain between two and one hundred siloxane repeating units. The polymer composition may be substantially free of compounds containing hydroxyl and / or carboxyl groups.

[0009] This invention allows for the modification of reactive polycarbonates with reactive siloxane compounds to form siloxane-modified polycarbonates, which possess properties such as improved molecular weight, flame retardancy, and / or reduced hydroxyl and / or carboxyl groups in the polymer composition. Reactive siloxane compounds are advantageous in recovery solutions containing recycled polycarbonates because such compounds can potentially be formed and used directly in the recycling solution, allowing for the formation of the reactive siloxane compound and the remediation of the recycled polycarbonate in the same step. The addition of reactive siloxane compounds can be used to alter the properties of the reactive polycarbonate and optionally remove smaller hydroxyl-containing compounds, such as bisphenol A. Attached Figure Description

[0010] Figure 1 This refers to the GPC analysis of the material after heating it to 300°C. Detailed Implementation

[0011] The technology of this invention allows for the modification of reactive groups in reactive polycarbonates to form siloxane-modified polycarbonates with flame retardancy, improved molecular weight, and / or other improved polymer properties. By reacting a reactive siloxane compound with one or more carboxyl and / or hydroxyl groups, the reactive siloxane compound provides the dual advantages of removing hydroxyl and / or carboxyl groups from reactive polycarbonates and improving the polymer properties of waste polycarbonates.

[0012] Siloxane-modified polycarbonate refers to a polycarbonate containing residues of a reactive siloxane compound. A reactive polycarbonate contains at least one reactive group as described herein. Siloxane-modified or reactive polycarbonate may comprise virgin polycarbonate, waste polycarbonate, or any combination thereof. Siloxane-modified polycarbonate as described herein contains at least residues of a reactive siloxane compound and a reactive polycarbonate. The term remediation refers to adjusting the molecular weight of waste or reactive polycarbonate to a different molecular weight or having a reduced number of carboxyl and / or hydroxyl terminal groups. A recovery solution comprises at least one solvent system and at least one polycarbonate compound. The solvent system comprises one or more solvents that may be miscible or immiscible. Waste polycarbonate refers to polycarbonate located in waste feedstock. Virgin polycarbonate refers to polycarbonate produced by one or more techniques of reacting one or more diols with carbonic acid to form polycarbonate. The functional compounds used herein may end, extend, or branch one or more polycarbonate chains, with or without reaction with one or more reactive siloxane compounds.

[0013] The waste material contains at least some waste polycarbonate. The waste material contains waste polycarbonate and at least one other waste non-polycarbonate compound, such as a metal compound. The waste material contains approximately 10% by weight to less than 100% by weight of waste polycarbonate. The non-polycarbonate compound includes one or more of metals, non-polycarbonate polymers, battery electrolytes, small organic compounds, oligomers, or any combination thereof. The non-polycarbonate compound may include one or more compounds that are typically mixed or blended with polycarbonate, including non-polycarbonate polymers (such as styrene, polystyrene, styrene-acrylonitrile, acrylonitrile-butadiene, butadiene elastomers, high-impact polystyrene, polymethyl methacrylate), flame retardants, UV stabilizers, fillers, antioxidants, other additives, other polymers, or any other non-polycarbonate compound. Examples of waste materials can include any non-polycarbonate material in any waste containing polycarbonate, such as housings for electronic devices, plastic waste, toys, packaging, conveyors, pallets, automotive parts, medical devices, household appliances, speakers, home furnishings, any other electronic devices including non-polycarbonate polymers, metals, printed circuit boards, batteries, magnets, or any combination thereof. Before contacting the waste material with polycarbonate solvents, some of the non-polycarbonate compounds in the waste material can be removed through one or more pretreatment steps, ensuring that some of the non-polycarbonate compounds do not undesirably dissolve in the polycarbonate solvent.

[0014] As used herein, "one or more" means that at least one or more of the listed components may be used as disclosed. As used herein, a hydrocarbon group refers to a group containing a backbone of one or more carbon atoms and hydrogen atoms, said group optionally containing one or more heteroatoms. When a hydrocarbon group contains heteroatoms, the heteroatoms may form one or more functional groups well known to those skilled in the art. A hydrocarbon group may contain alicyclic segments, aliphatic segments, aromatic segments, or any combination of such segments. Aliphatic segments may be straight-chain or branched. Aliphatic and alicyclic segments may contain one or more double and / or triple bonds. Hydrocarbon groups include alkyl, alkenyl, alkynyl, aryl, cycloalkyl, cycloalkenyl, alkylaryl, and aralkyl groups. Alicyclic groups may contain both cyclic and acyclic portions. A hydrocarbon group means a hydrocarbon group having more than one valence state or any subset described, such as alkylene, alkenyl, alkynyl, aryl, cycloalkylene, cycloalkenylene, alkylenearyl, and aralkylene. As used herein, valence refers to a covalent bond between a hydrocarbon or hydrocarbon-like group and another group, such as a group or atom containing a carbonyl, oxygen, nitrogen, or sulfur, or the base compound mentioned. Unless otherwise stated, weight percent or parts by weight as used herein refers to or is based on the weight of the composition. Tg is the temperature or range of temperatures at which the physical properties (including, for example, mechanical strength) of a polymer material change abruptly. Tg can be determined by differential scanning calorimetry (DSC). As used herein, post-industrial refers to the source of materials generated during the manufacture of goods or products. As used herein, post-consumer refers to the source of materials generated after the end consumer has used the material in a consumer product or product.

[0015] As used herein, a compound containing hydroxyl and / or carboxyl groups means a compound that contains at least one hydroxyl or carboxyl group bonded to a carbon atom and has a molecular weight of about 500 g / mol or less, about 2000 g / mol or less, or about 3000 g / mol or less. Compounds containing hydroxyl and / or carboxyl groups can be residues of polycarbonate and have the molecular weights described herein. Polycarbonate oligomers as described herein can be distinguished from compounds containing hydroxyl and / or carboxyl groups by having a number-average or weight-average molecular weight of 1000 g / mol or greater, 3000 g / mol or greater, or 5000 g / mol or greater. Compounds containing hydroxyl and / or carboxyl groups may contain more than one repeating unit or a derivative thereof, said repeating unit or derivative thereof being a residue of polycarbonate. The repeating unit of a compound containing hydroxyl and / or carboxyl groups can be those repeating units described with respect to the polycarbonate discussed herein, which are terminated with at least one hydroxyl or carboxyl group. Compounds containing hydroxyl and / or carboxyl groups may include one or more bisphenol A compounds or derivatives thereof. Compounds containing hydroxyl and / or carboxyl groups can be separated from the recovery solution by any of the techniques described herein, such as by contacting the solvent with the recovery solution to extract the compounds containing hydroxyl and / or carboxyl groups, using an absorbent or adsorbent to remove the compounds containing hydroxyl and / or carboxyl groups, using an additive to precipitate the compounds containing hydroxyl and / or carboxyl groups, applying a charge to the compounds to remove the compounds containing hydroxyl and / or carboxyl groups, filtering the compounds containing hydroxyl and / or carboxyl groups, or any other separation techniques described herein. After one or more separation steps in the recovery solution to remove the compounds containing hydroxyl and / or carboxyl groups, the polycarbonate solution may be substantially free of the compounds containing hydroxyl and / or carboxyl groups. The substantially free amount of compounds containing hydroxyl and / or carboxyl groups may be about 150 ppm or less, about 100 ppm or less, or about 50 ppm or less. The substantially free amount of compounds containing hydroxyl and / or carboxyl groups may be about 25 ppm or less, 10 ppm or less, or an amount undetectable by conventional known methods. Functional compounds, reactive and / or precursor siloxane compounds, and / or separation techniques can be used to remove hydroxyl and / or carboxyl groups to reduce the weight percentage of hydroxyl and / or carboxyl-containing compounds in the recovered solutions and / or polymer compositions described herein. The reduction of hydroxyl and / or carboxyl-containing compounds can be about 10% or more, about 30% or more, or about 50% or more. The reduction can be about 70% or more, about 90% or more, or about 95% or more. Hydroxyl and / or carboxyl-containing compounds can be determined by any technique known to those skilled in the art. As an example, free phenolic substances (including bisphenol-a, phenol, and tert-butylphenol) can be detected using HPLC equipped with a standard C18 column and a fluorescence detector at an excitation wavelength of 310 nm and emission monitored at 275 nm.Quantification can be accomplished using external standards of BPA and phenol. Sample preparation may involve dissolving 1 g of PC sample in 5 mL of dichloromethane, followed by the addition of 20 mL of acetonitrile under continuous shaking. The 2 mL supernatant is filtered through a 0.45 µm syringe filter and then analyzed using HPLC.

[0016] As used herein, polycarbonate refers to a polymer containing carbonate units. Such polymers can be homopolymers consisting essentially of carbonate monomer units or copolymers containing one or more other monomer units (comonomer units) and carbonate units. Such copolymers can be block copolymers containing blocks of two or more different monomer units, or random copolymers in which different monomer units are randomly distributed along the polymer backbone. Other monomer units may include any monomer unit that does not negatively affect the inherent properties of polycarbonate, such as heat resistance, impact resistance, moldability, flexural modulus, flexural strength, haze, and transparency, if required by the intended use. Exemplary comonomer units are ester units, polysiloxane units, etc. As disclosed herein, the amount of carbonate monomer units in the copolycarbonate is selected such that the resulting polymer retains the desired properties of polycarbonate. Copolycarbonates may contain more than 50 mol% carbonate monomer units, about 75 mol% or more carbonate monomer units, about 80 mol% or more carbonate monomer units, or about 85 mol% or more carbonate monomer units. Copolycarbonates may contain about 99 mol% or less of carbonate monomer units, about 97 mol% or less of carbonate monomer units, or about 95 mol% or less of carbonate monomer units. Copolycarbonates may contain about 1 mol% or more of comonomer units, about 3 mol% or more of comonomer units, or about 5 mol% or more of comonomer units. Copolycarbonates may contain less than 50 mol% of comonomer units, about 25 mol% or less of comonomer units, about 20 mol% or less of comonomer units, or about 15 mol% or less of comonomer units. The polycarbonate units may contain aromatic units in the polymer backbone. The polycarbonates used herein may contain any amount of virgin and / or waste polycarbonate as needed to achieve desired flame retardancy, molecular weight, and / or other desired properties. For example, the compositions and polymers of the present invention may contain about 10% or more, about 30% or more, or about 50% or more of virgin or waste polycarbonate. The compositions and polymers of the present invention may contain about 100% or less, about 80% or less, or about 60% or less of virgin or waste polycarbonate.

[0017] Polycarbonate production is achieved, for example, by a phase-interval process, optionally using a chain terminator (e.g., monophenol) and optionally a trifunctional branching agent or a branching agent with a functionality greater than three (e.g., triphenol or tetraphenol), by reacting the bisphenol with a carbonate halide (preferably phosgene) and / or with an aromatic dicarboxylic acid dihalide (preferably benzene dicarboxylic acid dihalide). The bisphenols that can be used to produce aromatic polycarbonates and / or aromatic polyester carbonates can correspond to... Formula I Where A represents a single bond, and C represents a single bond. 1-5 Alkylene, C 2-5 Phenylene, C 5-6 Hypocycloalkyl, -O-, -SO-, -CO-, -S-, -SO2- or C 6-12 An aryl group, which may be fused with other aromatic rings optionally containing heteroatoms, or groups of formula II or III: II Or III Where B is hydrogen independently in each case, and C 1-12 Alkyl (preferably methyl) or halogen (preferably chlorine and / or bromine); x is 0, 1, or 2 independently in each case; p is 0 or 1; R c and R d They are independent of each other and for each X 1 It can be selected individually, and is either hydrogen or C. 1-6 Alkyl groups, preferably hydrogen, methyl, or ethyl; X 1 It represents carbon; and m represents an integer from 4 to 7, preferably 4 or 5, provided that R c and R d Simultaneously represents at least one X 1 Alkyl group on an atom.

[0018] Exemplary diphenols include hydroquinone, resorcinol, dihydroxybiphenyl, and bis(hydroxyphenyl)-C. 1-5 Alkanes, bis(hydroxyphenyl)-C 5-6Cycloalkanes, bis(hydroxyphenyl) ethers, bis(hydroxyphenyl) sulfoxides, bis(hydroxyphenyl) ketones, bis(hydroxyphenyl) sulfones, and 4,4″-bis(hydroxyphenyl)diisopropylbenzene, and their derivatives having brominated and / or chlorinated nuclei. Particularly preferred bisphenols are 4,4'-dihydroxybiphenyl, bisphenol A, 2,4-bis(4-hydroxyphenyl)-2-methylbutane, 1,1-bis(4-hydroxyphenyl)-cyclohexane, 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, 4,4-dihydroxydiphenyl sulfide, and 4,4-dihydroxydiphenyl sulfone, and their dibrominated and tetrabrominated or chlorinated derivatives, such as 2,2-bis(3-hydroxyphenyl)-diphenyl sulfone. Bisphenol A (BPA), 2,2-bis(3,5-dichloro-4-hydroxyphenyl)propane, or 2,2-bis(3,5-dibromo-4-hydroxyphenyl)propane, is particularly preferred. Bisphenol A can be used alone or in any mixture. Bisphenol A is known from the literature or can be obtained by methods known from the literature. In addition to BPA homopolymers, exemplary polycarbonates include copolycarbonates of BPA with up to 15 mol% of other disclosed bisphenols such as 2,2-bis(3,5-dibromo-4-hydroxyphenyl)propane relative to the total molar amount of the bisphenol A.

[0019] To end-cap, branch, or extend the polycarbonate used in this disclosure, one or more functional compounds may be used in combination with one or more reactive siloxane compounds. The functional compounds may include one or more chain extenders, chain terminators, branching agents, or combinations thereof. The functional compounds used herein end-cap, extend, or branch one or more polycarbonate chains without or in combination with a precursor and / or a reactive siloxane compound. The functional compounds may be added to the recovery solution individually or continuously, one at a time, over one or more time periods, to branch and / or extend the chain, followed by chain termination to obtain the desired molecular weight and related properties. One or more functional compounds may be added to the recovery solution in an amount sufficient to reduce the amount of hydroxyl groups to the desired level, thereby extending and / or branching the polycarbonate chain. One or more functional compounds may be added to the recovery solution in an amount of about 0.01% by weight or more, about 0.1% by weight or more, or about 0.5% by weight or more, based on the total weight of the waste polycarbonate in the recovery solution. One or more functional compounds may be added to the recycling solution in an amount of about 10% by weight or less, about 5% by weight or less, or about 1% by weight or less, based on the total weight of the waste polycarbonate in the recycling solution.

[0020] Chain terminators can be configured to react with at least one free hydroxyl and / or carboxyl groups of one or more waste and / or siloxane-modified polycarbonates to terminate the chain, react with a non-polycarbonate compound to remove the free hydroxyl and / or carboxyl groups, or both. The chain terminators described herein can be configured to bind to one or more hydroxyl or carboxyl groups in a recovery solution such that the free hydroxyl and / or carboxyl groups do not cleave one or more polycarbonate polymers. Chain terminators can include one or more groups that can react with one or more hydroxyl or carboxyl groups in a condensation reaction. Chain terminators can be used to terminate the chains of one or more waste and / or siloxane-modified polycarbonates. Chain terminators can be used to bind to one or more non-polycarbonate compounds such that the free hydroxyl and / or carboxyl groups of the non-polycarbonate compound (e.g., carboxyl- and / or hydroxyl-containing compounds) are removed from the recovery solution and / or the polycarbonate chains are prevented from cleaving due to undesirable interactions of the hydroxyl and / or carboxyl groups. The chain terminator can be any compound that reacts with hydroxyl and / or carboxyl groups without adversely affecting the usability of the resulting polycarbonate. Exemplary chain terminators may include one or more isocyanates, amines, esters, epoxides, acid anhydrides, carboxylic acids, or any combination thereof.

[0021] Chain terminators may include one or more phenolic compounds. Phenolic compounds may include phenol, p-chlorophenol, p-tert-butylphenol, 4-(1,3-dimethyl-butyl)phenol, and 2,4,6-tribromophenol; long-chain alkylphenols, such as monoalkylphenols or dialkylphenols having a total of 8 to 20 carbon atoms in their alkyl substituents, exemplarily 3,5-di-tert-butylphenol, p-isooctylphenol, p-tert-octylphenol, p-dodecylphenol, 2-(3,5-dimethylheptyl)phenol, and 4-(3,5-dimethylheptyl)phenol.

[0022] The branching agent used in this disclosure can be any compound capable of reacting with three or more carboxyl and / or hydroxyl groups, individually or separately, on the same or individual polycarbonate compound. The branching agent can have a functionality of three or more, four or more, five or more, or six or more. Functionality is a measure of the ability to bind with a single hydroxyl and / or carboxyl group. The branching agent can react with three or more, four or more, five or more, or more hydroxyl and / or carboxyl groups. Polycarbonate can be branched, for example, by incorporating about 0.05 to about 2.0 mol% of a trifunctional compound or a compound with a functionality greater than three, such as those containing three or more phenolic groups, relative to the total amount of the branching agent used. Branched polycarbonates that can be used in the disclosed compositions can be prepared by known techniques, for example, several methods disclosed in USP 3,028,365, 4,529,791, and 4,677,162 (which are hereby incorporated in their entirety by reference). Exemplary branching agents include trifunctional or polyfunctional carboxylic acid chlorides, such as pyromellitic acid trichloride, cyanuric acid trichloride, 3,3'-,4,4'-benzophenone tetracarboxylic acid tetrachloride, 1,4,5,8-naphthalene-tetracarboxylic acid tetrachloride, or pyromellitic acid tetrachloride, in an amount of about 0.01 to about 1.0 mol% (relative to the dicarboxylic acid dichloride used); or trifunctional or polyfunctional phenols, such as phloroglucinol, 4,6-dimethyl-2,4,6-tris(4-hydroxyphenyl)-2-heptene, 4,4-dimethyl-2,4,6-tris(4-hydroxyphenyl)heptane, 1,3,5-tris(4-hydroxyphenyl)-benzene, 1,1,1-tris(4-hydroxyphenyl)ethane, tris(4-hydroxyphenyl)-phenyl-methane, 2,2-bis[4,4-bis(4- The amounts of bis(4-hydroxyphenyl)cyclohexyl)propane, 2,4-bis[1-(4-hydroxyphenyl)-1-methyl-ethyl]phenol, tetra(4-hydroxyphenyl)methane, 2,6-bis(2-hydroxy-5-methyl-benzyl)-4-methyl-phenol, 2-(4-hydroxyphenyl)-2-(2,4-dihydroxyphenyl)propane, or tetra(4-[1-(4-hydroxyphenyl)-1-methylethyl]phenoxy)methane are about 0.01 to about 1.0 mol% (relative to the bisphenol used). Phenolic branching agents can be added to the reaction vessel together with the bisphenol. Acyl chloride branching agents can be introduced together with the acyl chloride.

[0023] Chain extenders can include any compound having sufficient groups to bind two separate polycarbonate chains together. Chain extenders can be configured to react with two separate carboxyl and / or hydroxyl groups, such that the polycarbonate chain is extended or free carboxyl and / or hydroxyl groups are removed from the recovery solution. Chain extenders can contain at least two groups sufficient to react separately with two different polycarbonate chains and / or free hydroxyl and / or carboxyl groups. Chain extenders can be used to combine with one or more non-polycarbonate compounds, such that free hydroxyl and / or carboxyl groups are removed from the recovery solution and / or the polycarbonate chains are prevented from breaking due to undesirable interactions of hydroxyl and / or carboxyl groups. Combinations of chain extenders can be used to bind polycarbonates with different end groups. Examples of chain extenders can include two or more functional groups, including isocyanates, amines, esters, epoxides, acid anhydrides, carboxylic acids, or any combination thereof.

[0024] The solvent system may contain one or more solvents or only one solvent, such as a polycarbonate solvent. The solvent system may contain two solvents present in miscible concentrations. The solvent system may contain two or more solvents such that a portion of the solvent system contains some water dissolved in one or more polycarbonate solvents and some water phase-separated from the polycarbonate solvents. The miscibility of the two solvents may be affected or varied based on the temperature or pressure applied to the recovery solution. The solvent system may contain miscible amounts of polycarbonate and water, such as about 0.6% by weight or less, about 0.4% by weight or less, about 0.2% by weight or less, or about 0.1% by weight based on the total weight of the solvent system or recovery solution. In some instances, water may be present in the solvent system in an amount exceeding the miscible amount of water in the polycarbonate solvent. In cases where water participates in one or more reactions described herein, such as reactions with precursor siloxane compounds that form reactive siloxane compounds, water may react within the polycarbonate solvent, and when the reaction occurs, excess water may dissolve into the polycarbonate solvent. One or more separation steps can be used to remove unwanted amounts or substantially all of the water (e.g., until the solvent system contains 0.1 or less, 0.01 or less, or 0.001 or less water). Water can be removed from the solvent system before or after the reactive polycarbonate is dissolved. Instead of water, the solvent system can contain one or more other polar protic solvents configured to adjust the miscibility of components in the recovered solution or participate in one or more reactions, such as in the formation of siloxane-modified polycarbonate or reactive siloxane compounds. Examples of other polar protic solvents may include methanol, ethanol, n-propanol or isopropanol, n-butanol or tert-butanol, acetic acid, ammonia, formic acid, or any combination thereof.

[0025] The function of a polycarbonate solvent is to dissolve solid polycarbonate in waste feedstocks. A polycarbonate solvent can dissolve one or more waste polycarbonates in the waste feedstock, but not one or more other non-polycarbonate polymers and other materials present in the waste stream that could negatively impact the use of the recovered polycarbonate. A polycarbonate solvent can have a boiling point sufficient to be heated to a temperature that will not cause the polycarbonate chains to break. A polycarbonate solvent can have a boiling point of about 25°C or higher, about 40°C or higher, or about 60°C or higher. A polycarbonate solvent can have a boiling point of about 160°C or lower, about 120°C or lower, or about 80°C or lower. A polycarbonate solvent can be any solvent that preferentially dissolves polycarbonate relative to other polymers and materials present in the waste stream that could negatively impact the use of the recovered polymer. A polycarbonate solvent can be a polar aprotic solvent. A polycarbonate solvent can contain at least one halogen atom. A polycarbonate solvent can be free of one or more reactive protons. A polycarbonate solvent can be free of one or more carboxyl and / or hydroxyl groups. Polycarbonate solvents may not react with one or more carboxyl and / or hydroxyl groups. Polycarbonate solvents may be immiscible with polar protic solvents such as water, allowing them to be used in devolatilization processes to recover polycarbonate solvents and to recover siloxane-modified polycarbonate in solid form separately. Polycarbonate solvents may contain one or more of the following: chloroform, dichloromethane, chlorobenzene, dichlorobenzene, tetrahydrofuran, 2-methyltetrahydrofuran, N-methyl-2-pyrrolidone, dimethylformamide, 1,4-dioxane, methyl ethyl ketone, ethyl acetate:ethanol (3:1, binary solvent), dimethyl sulfoxide, or any combination thereof.

[0026] This disclosure provides techniques for modifying reactive polycarbonate polymers and oligomers with reactive siloxane compounds to formulate polymers having imparted flame retardancy, higher molecular weight, fewer hydroxyl and / or carboxyl groups, and / or reduced hydroxyl and / or carboxyl groups in the polymer composition. By integrating siloxane compounds into the polycarbonate chain, siloxane units can be added within and / or along the polycarbonate backbone, resulting in one or more properties of the siloxane-modified polycarbonate. Furthermore, to simplify the recycling of waste polycarbonate, reactive siloxane compounds can be formed in situ and / or the same solvent systems used to dissolve waste polycarbonate can be used, thereby reducing separation and processing steps. Using these techniques, siloxane-modified polycarbonate can be further combined with techniques for integrating chain extenders and branching agents to obtain polycarbonate with desired flame retardancy, reduced hydroxyl and / or carboxyl groups in the polymer composition, and increased molecular weight.

[0027] Waste polycarbonate (e.g., reactive polycarbonate) contains reactive groups formed from the degradation of virgin polycarbonate over time. The reactive siloxane compounds disclosed herein can readily contact the reactive groups of waste polycarbonate and be integrated into existing waste polycarbonate to improve molecular weight and modulate the properties of the polycarbonate.

[0028] Reactive polycarbonates may contain one or more reactive groups (e.g., carboxyl, hydroxyl, and / or phenolic groups) configured to react with acetoxy, methoxy, ethoxy, halide, and / or hydrogen groups of a reactive siloxane compound. In the case where the reactive polycarbonate is a recycled and unmodified polycarbonate polymer and / or oligomer, the reactive polycarbonate may contain one or more hydroxyl, phenolic, or carboxyl groups at the ends or along the main chain, formed by the natural degradation of the polymer over time. Natural degradation may occur due to exposure to extreme temperatures and / or sunlight (i.e., UV radiation). Before contacting the reactive siloxane compound with the reactive polycarbonate, the reactive polycarbonate or virgin polycarbonate described herein may be modified to introduce free hydroxyl, phenolic, and / or carboxyl groups at the ends and / or along the main chain into the polymer, thereby enabling the polycarbonate to react with the acetoxy, methoxy, ethoxy, halide, and / or hydrogen groups of the reactive siloxane compound. For example, waste or virgin polycarbonate can be hydroxylated by any means sufficient to form a reactive polycarbonate containing one or more hydroxyl, phenolic, and / or carboxyl groups. Hydroxylation of virgin and / or reactive polycarbonate can be carried out by oxidizing the polycarbonate, by exposing the polycarbonate to ultraviolet light to degrade the polycarbonate, and / or by hydrolyzing one or more virgin and / or waste polycarbonate. Reactive polycarbonate may contain any amount of hydroxyl and / or carboxyl groups at the ends or along the main chain, and reactive siloxane compounds may bind to said hydroxyl and / or carboxyl groups, such that free hydroxyl and / or carboxyl groups are reduced or eliminated in the modified siloxane compound. Additionally, reactive polycarbonate in the composition may include undesirable amounts of hydroxyl and / or carboxyl-containing compounds, which can be reduced by introducing the separation steps and / or reactive siloxane compounds described herein.

[0029] By adjusting the reactive groups of reactive polycarbonate, reactive siloxane compounds and desired functional compounds can be linked to polycarbonate in a desired order, thereby imparting flame retardancy, reducing hydroxyl and / or carboxyl groups in the polymer composition, repairing and / or controlling the molecular weight, and / or removing hydroxyl, phenolic, and carboxyl groups from the reactive polycarbonate. The reactive siloxane compound and reactive polycarbonate can be contacted first to form a bond having a reactive siloxane compound-reactive polycarbonate chain sequence, and subsequently, the functional compound can be contacted with the reactive siloxane compound-reactive polycarbonate to form a siloxane-modified polycarbonate having a functional compound-reactive siloxane compound-reactive polycarbonate chain sequence. Alternatively, the functional compound and reactive polycarbonate can be contacted to form a bond having a functional compound-reactive polycarbonate chain sequence, and subsequently, the functional compound can be contacted with the functional compound-reactive polycarbonate to form a chain polycarbonate having a reactive siloxane compound-functional compound-reactive polycarbonate reaction sequence. In the case of siloxane-modified polycarbonates having a chain sequence of reactive siloxane compound-functional compound-reactive polycarbonate or a chain sequence of functional compound-reactive siloxane compound-reactive polycarbonate, the siloxane-modified polycarbonate can subsequently be contacted with another reactive siloxane compound, functional compound, and / or reactive polycarbonate polymer or oligomer, or any combination thereof, to impart the desired flame retardancy within the polymer chain, obtain the desired molecular weight, and / or remove hydroxyl, phenolic, and / or carboxyl groups from the reactive polycarbonate to form a siloxane-modified polycarbonate. At any free reactive group in the reactive polycarbonate, a functional compound or reactive siloxane compound can be added to end-cap or to combine two or more polycarbonate chains.

[0030] The siloxane modifiers used herein are configured to integrate siloxane units within and / or along the backbone of siloxane-modified polycarbonate. The siloxane modifier can be any siloxane compound containing repeating siloxane units, said siloxane compound containing at least one acetoxy, methoxy, ethoxy, halide, and / or hydrogen group configured to react with hydroxyl, carboxyl, and / or phenolic groups of the reactive polycarbonate. The siloxane modifier can contain, for example, 1 to 100 siloxane units. The siloxane modifier can include precursors and / or reactive siloxane compounds. The siloxane modifier can be contacted with the reactive polycarbonate before or after it is dissolved in a solvent system. The siloxane modifier can be configured to react in a solvent system to form a multi-unit siloxane.

[0031] Precursor siloxane compounds can be used as the basis for reactive siloxane compounds. Precursor siloxane compounds may comprise a silicon or silane group substituted with at least one halide, acetoxy, ethoxy, and / or methoxy group, and optionally one or more hydrogen and / or alkyl groups. Precursor siloxanes containing at least one halide, acetoxy, ethoxy, and / or methoxy group can be configured to react with one or more water molecules dissolved in a solvent system to form a reactive siloxane compound having one or more terminal halide, acetoxy, ethoxy, and / or methoxy groups: At least one of R a Contains hydrogen, methoxy, acetoxy, and / or halide groups, and each R a It may independently contain halides, methoxy, ethoxy, acetoxy, hydrogen or straight-chain or branched alkyl, aryl, alkyl-aryl, aryl-alkyl, heteroalkyl or heteroaryl groups or any combination thereof.

[0032] Following reaction with water molecules, one or more acids may be generated as byproducts in the formation of reactive siloxane compounds or siloxane-modified polycarbonates. These acids can be removed from the solvent system before, during, or after contact of the reactive polycarbonate with the solvent system by one or more scavengers as described herein. The precursor siloxane compound may be configured to introduce siloxane units along or within the backbone of the reactive polycarbonate, thereby forming a siloxane-modified polycarbonate with an increased molecular weight relative to the reactive polycarbonate. The precursor siloxane may comprise any number of halide, acetoxy, ethoxy, and / or methoxy groups configured to react with one or more free hydroxyl, carboxyl, and / or phenolic groups of the reactive polycarbonate. The precursor siloxane compound may include monomethoxysilanes, dimethoxysilanes, trimethoxysilanes, and / or tetramethoxysilanes. The precursor siloxane compound may include monoethoxysilanes, diethoxysilanes, triethoxysilanes, and / or tetraethoxysilanes. Precursor compounds may include monoacetoxysilanes, diacetoxysilanes, triacetoxysilanes, and / or tetraacetoxysilanes. Precursor siloxane compounds may include monohalosilanes, dihalosilanes, trihalosilanes, and / or tetrahalosilanes. Precursor siloxane compounds may be contacted with the solvent system before, during, or after the reactive polycarbonate is dissolved in the solvent system. Precursor siloxane compounds may be soluble in the polycarbonate solvent or may be immiscible with the polycarbonate solvent. Precursor siloxane compounds may be added to the solvent system in any amount sufficient to integrate the siloxane unit into the reactive polycarbonate. In some instances, the precursor siloxane compound may be directly linked to the reactive polycarbonate before the formation of the reactive siloxane compound. Some precursor siloxane compounds may react with water to form longer-chain reactive siloxane compounds, and some precursor siloxane compounds may react with the reactive polycarbonate to end-cap, chain-extend, crosslink, or branch the reactive polycarbonate to form a siloxane-modified polycarbonate. The precursor siloxane compound may be added to the solvent system in an amount of about 0.1% by weight or more, about 1% by weight or more, or about 3% by weight or more, based on the total weight of the solvent system. The precursor siloxane compound may be added to the solvent system in an amount of about 10% by weight or less, about 8% by weight or less, or 5% by weight or less.

[0033] Reactive siloxane compounds are used to integrate siloxane units into reactive polycarbonates to form siloxane-modified polycarbonates. The reactive siloxane can be configured to optionally bind to the reactive polycarbonate at one or more sites in the reactive polycarbonate in the presence of a catalyst suitable for forming the siloxane-modified polycarbonate. Reactive sites include free carboxyl, hydroxyl, phenolic, and / or olefinic groups along the main chain of the polycarbonate or at the ends of the polycarbonate. The reactive siloxane compound may contain any group configured to react and bind to the reactive polycarbonate at the reactive sites. Examples of groups configured to react or bind to reactive sites may include methoxy, ethoxy, acetoxy, halide, and / or hydrogen groups. The reactive siloxane compound may include any number of halide, methoxy, ethoxy, acetoxy, and / or hydrogen groups configured to react or bind to the reactive sites of the reactive polycarbonate. Reactive siloxane compounds may include a plurality of methoxy, ethoxy, acetoxy, halide, and / or hydrogen groups configured to end-cap, chain-extend, branch, and / or crosslink the reactive polycarbonate, thereby achieving the desired molecular weight of the siloxane-modified polycarbonate. Reactive siloxane compounds may contain methoxy, acetoxy, ethoxy, halide, and / or hydrogen groups at different ends, on different silicon atoms, or on the same silicon atom. Reactive siloxane compounds may contain one or more, two or more, three or more, four or more, five or more, or more methoxy, acetoxy, ethoxy, halide, and / or hydrogen groups configured to end-cap, chain-extend, branch, and / or crosslink the reactive polycarbonate. Reactive siloxane compounds may contain any number of siloxane units sufficient to introduce hydroxyl and / or carboxyl groups, or any combination thereof, sufficient to introduce an increase in molecular weight, impart flame retardancy, or reduce the presence of hydroxyl and / or carboxyl groups in the polymer composition. The reactive siloxane compound may contain one or more, 10 or more, or 20 or more siloxane units. The reactive siloxane compound may contain 100 or fewer, 70 or fewer, or 50 or fewer siloxane units. The reactive siloxane compound may be added to the solvent system in any amount sufficient to increase the molecular weight of the reactive polycarbonate and / or sufficient to remove carboxyl and / or hydroxyl-containing compounds from the recovery solution, or in combination with carboxyl and / or hydroxyl-containing compounds in the recovery solution. The reactive siloxane compound may be added to the solvent system in an amount of about 0.1% by weight or more, about 1% by weight or more, or about 3% by weight or more based on the total weight of the solvent system. The reactive siloxane compound may be added to the solvent system in an amount of about 10% by weight or less, about 8% by weight or less, or 5% by weight or less. The reactive siloxane compound may additionally or alone reduce the amount of hydroxyl-containing compounds in the recovery solution.Reactive siloxane compounds can be used to bind polycarbonate polymers and / or oligomers together, and / or to bind with hydroxyl-containing compounds, such that the final polycarbonate composition contains fewer free hydroxyl and / or carboxyl groups.

[0034] Reactive siloxane compounds can have structures according to the following formula: Where m is an integer from 1 to 100, and at least one R a It contains methoxy, ethoxy, acetoxy, halide, and / or hydrogen groups, and each R a It may independently contain methoxy, acetoxy, ethoxy, halide, hydrogen or straight-chain or branched alkyl, aryl, alkyl-aryl, aryl-alkyl, heteroalkyl or heteroaryl groups or any combination thereof.

[0035] Allyl halides can be configured to react with the hydroxyl and / or phenolic groups of polycarbonate to form acid- and vinyl ether-terminated polycarbonate. When a siloxane compound is terminally terminated with at least one hydrogen atom or contains at least one hydrogen atom, the siloxane compound can be configured to react with the vinyl groups of the vinyl ether-terminated polycarbonate, such that, optionally in the presence of a suitable catalyst, a siloxane-modified polycarbonate is formed. The siloxane units of the siloxane-modified polycarbonate can be linked to the polycarbonate units via one or more alkyl, aryl, alkyl-aryl, or arylalkyl groups, said groups being residues of the allyl halide. Allyl halides can be added to the solvent system in an amount sufficient to extend, terminate, and / or branch the reactive polycarbonate. Allyl halides can be added as a weight percentage of about 0.1% or more, about 0.5% or more, or about 1% or more based on the total weight of the solvent system. Allyl halides may be added in weight percentages of about 5% by weight or less, about 3% by weight or less, or about 2% by weight or less, based on the total weight of the solvent system. Allyl halides may be added to the solvent system in a molar ratio relative to the reactive siloxane compound, resulting in the desired molecular weight increase. Allyl halides and reactive siloxane compounds may contact in the solvent system in a molar ratio of about 4:1 or higher, about 3:1 or higher, or about 2:1 or higher. Allyl halides and reactive siloxane compounds may contact in the solvent system in a molar ratio of about 1:1 or lower, about 1:2 or lower, or about 1:4 or lower. Allyl halides may have any structure linking the olefin and the halide. Allyl halides may have any structure with one end capped with a halide and the other end capped with an olefin. Allyl halides may contain one or more straight-chain or branched alkyl, aryl, alkylaryl, arylalkyl groups, or any combination thereof between the olefin and the halide. Allyl halides can have structures according to the following formula: Where Ha is any halide, and R b It is one or more straight-chain or branched alkyl, aryl, alkylaryl, arylalkyl groups or any combination thereof, and wherein x is an integer from 1 to 10.

[0036] Vinyl ether-terminated polycarbonates can have a structure according to the following formula: Where R b It is one or more straight-chain or branched alkyl, aryl, alkylaryl, arylalkyl groups or any combination thereof, wherein x is an integer from 1 to 10, and wherein PC is a residue of reactive polycarbonate.

[0037] After contacting vinyl ether-terminated polycarbonate with a reactive siloxane compound, the siloxane-modified polycarbonate can have a structure according to the following formula: Where R b It is one or more straight-chain or branched alkyl, aryl, alkylaryl, arylalkyl, or any combination thereof, where x is an integer from 1 to 10, where m is an integer from 1 to 100, and at least one R a It is a hydrogen or halide atom, where each R a It may independently contain a halide, hydrogen or a straight-chain or branched alkyl, aryl, alkyl-aryl, aryl-alkyl, heteroalkyl or heteroaryl group or any combination thereof, and wherein PC is a residue of a reactive polycarbonate.

[0038] Following the formation of a reactive siloxane compound or a siloxane-modified polycarbonate, one or more acids may be generated as byproducts of the reaction. The acids described herein may include any acid compound containing halide, methoxy, ethoxy, and / or acetoxy groups, such as halide acids or acetic acid. Halide acids may include hydrochloric acid, hydrobromic acid, hydrofluoric acid, or any combination thereof. The acids formed herein may be removed before, during, or after the addition of the reactive polycarbonate or the formation of the siloxane-modified polycarbonate by any separation step known to those skilled in the art.

[0039] This disclosure provides a polymer composition comprising a siloxane-modified polycarbonate as described herein. Specifically, residues of a reactive siloxane compound may be linked to polycarbonate units at oxygen atoms or at the ends of polycarbonate segments along the backbone of the polycarbonate chain. After the formation of the siloxane-modified polycarbonate, the siloxane-modified polycarbonate may be removed from a recovery solution by the separation steps described herein to remove the polycarbonate from the recovery solution or other liquid. The siloxane-modified polycarbonate and / or polymer composition may be substantially free of (i.e., containing 1 wt% or less, 0.1 wt% or less, or 0.01 wt% or less) solvent systems and / or compounds containing hydroxyl and / or carboxyl groups. The siloxane-modified polycarbonate may contain one or more polycarbonate segments linked by residues of a reactive siloxane compound, thereby forming a siloxane-polycarbonate copolymer. The siloxane-modified polycarbonate may be a branched or unbranched siloxane-polycarbonate copolymer of repeating siloxane units and polycarbonate segments. The amount of branching can originate from a reactive siloxane compound having three or more methoxy, ethoxy, acetoxy, halide, and / or hydrogen groups connecting three distinct polycarbonate segments. In other instances, the amount of branching can originate from a reactive polycarbonate having at least three hydroxyl and / or carboxyl groups configured to bind to a reactive siloxane group. The polycarbonate segments can be based on residues of waste polycarbonate polymers or oligomers having any number of repeating polycarbonate units. For siloxane blocks, the siloxane-modified polycarbonate can contain any number of siloxane units in each block. Each siloxane block can contain one or more, four or more, or ten or more siloxane units. Each siloxane block can contain one hundred or fewer, seventy-five or fewer, or fifty or fewer siloxane units.

[0040] This application provides polymerizable compositions comprising any amount of the components described herein present in waste feedstock or used to form siloxane-modified polycarbonates. For example, a polymerizable composition may comprise one or more acids, a siloxane modifier (e.g., reactive and / or precursor siloxane compounds), a reactive and / or virgin polycarbonate, a catalyst configured to form a siloxane-modified polycarbonate, a solvent system, a non-polycarbonate compound, waste feedstock, or any combination thereof. One or more reactive polycarbonates and a siloxane modifier may react in a solvent system of the polymerizable composition to form one or more siloxane-modified polycarbonates.

[0041] Polycarbonate or polymerizable compositions may contain any amount of waste polycarbonate, polycarbonate segments, or residues thereof sufficient to achieve the desired assembly of the recycled component. For example, polycarbonate or polymerizable compositions may contain about 5% or more, about 15% or more, or about 25% or more of waste polycarbonate, polycarbonate segments, or residues thereof. Polycarbonate or polymerizable compositions may contain about 100% or less, about 80% or less, or about 50% or less of waste polycarbonate, polycarbonate segments, or residues thereof.

[0042] In downstream process applications, siloxane-modified polycarbonate can be contacted with one or more compounds desired for the preparation of downstream products or compositions. Siloxane-modified polycarbonate can be blended or mixed with one or more other polymers or virgin polycarbonate to achieve the desired properties. Other polymers may include polystyrene, styrene-acrylonitrile, acrylonitrile-butadiene, styrene, high-impact polystyrene, polymethyl methacrylate, polyolefins, or any combination thereof. Siloxane-modified polycarbonate can be blended or mixed with one or more additives sufficient to achieve the desired properties using known techniques for blending additives with polymer compositions. Additives may include one or more of fillers, flame retardants, pigments, UV stabilizers, antioxidants, release agents, dyes, or any combination thereof.

[0043] Any technique or combination of techniques can be used to contact polycarbonate solvents, precursors and / or reactive siloxane compounds, reactive polycarbonates and / or waste materials, such that the polycarbonate solvent dissolves or disperses the components in the recovery solution, thereby achieving the desired surface contact between the components.

[0044] The recovered solution can be contacted in any housing sufficient to contain fluids (e.g., liquids and / or gases). The recovered solution can also be contacted in a sealed housing configured to contain both fluids and gases, such that waste materials and / or reactive polycarbonates can be mixed with the fluids and gases to achieve desired dissolution levels of the reactive polycarbonates and / or waste materials. Waste materials can be moved into the sealed housing through an inlet point and into contact with the polycarbonate solvent, such that minimal or no polycarbonate solvent loss occurs through the inlet point as the waste materials move into and out of the sealed housing.

[0045] The recycled solution can be formed and mixed within a housing configured to apply heating and cooling in a series of sections within the housing, allowing liquid and gaseous polycarbonate solvents to be applied at different locations. The housing may include bottom and middle sections that can be optionally heated, and a top section that can be optionally cooled, wherein waste materials and / or reactive polycarbonate can move into the housing in any section, and the top section cools the solvent while heat is applied in the middle or bottom sections to evaporate the polycarbonate solvent, preventing solvent from escaping through the top of the housing.

[0046] Before, during, or after contact with polycarbonate solvents, solvent systems, and waste materials, heat and / or agitation can be applied to the recycled solution to improve the dissolution time or mixing of reactive polycarbonates and / or precursors and / or reactive siloxane compounds into the polycarbonate solvent. Heating and / or agitation can be applied in combination, alone, or continuously to achieve desired concentration levels, saturation, dispersion, mixing, and / or dissolution times of the reactive polycarbonates and / or precursors and / or reactive siloxane compounds in the polycarbonate solvent. Heating and / or agitation can provide, alone or in combination, techniques for controlling the physical state (e.g., gas, liquid, solid) of the polycarbonate solvent, reactive polycarbonates, and / or precursors and / or reactive siloxane compounds.

[0047] The housing may be equipped with any instrument sufficient to apply heating and / or cooling to control the physical state of the polycarbonate solvent and improve the dissolution and mixing of reactive polycarbonates and / or precursors and / or reactive siloxane compounds. Heating and / or cooling may be applied by any means sufficient to regulate the temperature of the recovered solution. The housing may be equipped with one or more, two or more, three or more, or a greater number of heating and / or cooling instruments to manipulate the temperature of the recovered solution. The instruments for heating and cooling may be in the same section, or may be located in separate locations and / or sections, such that the state of the recovered solution is controlled and / or the polycarbonate solvent is prevented from escaping from the housing. Agitation may be applied to the solvent system or polycarbonate solvent in a liquid state, and separately to the solvent system or polycarbonate solvent in a gaseous state. Any type of agitation that enhances the dissolution of reactive polycarbonates and / or precursors and / or reactive siloxane compounds into the polycarbonate solvent may be provided. The housing may be equipped with multiple instruments configured to apply agitation in a single state. The housing may be equipped with an ultrasonic treatment device (i.e., for applying ultrasonic waves) and a stirring device, allowing the use of two or more techniques to improve agitation and subsequently improve the dissolution of waste polycarbonate into a polycarbonate solvent. Examples of agitators may include an ultrasonic generator, an impeller, a magnetic stirrer, a vortex mixer, a rocker arm, an oscillator, or any combination thereof.

[0048] Agitation can move dissolved waste polycarbonate molecules away from the waste material, thus dissolving additional waste polycarbonate into the polycarbonate solvent and allowing the entire recovery solution to reach the desired total concentration or saturation in a shorter time. Agitation can be used on the polycarbonate solvent surrounding the waste material and / or reactive polycarbonate to mix the polycarbonate solvent and reduce local saturation of polycarbonate at a particular location in the recovery solution. Agitation can be applied for any duration or with any force sufficient to move reactive polycarbonate and / or precursor and / or reactive siloxane compound molecules within the polycarbonate solvent and achieve the desired concentration or saturation in the recovery solution. Combinations of agitation can be used on both the polycarbonate solvent and the waste material, the reactive polycarbonate and / or precursor and / or reactive siloxane compound, or the container holding the waste material, causing polycarbonate molecules to move within the polycarbonate solvent. When ultrasound is applied from an external ultrasonic treatment device, the container holding the waste material can be vibrated or shaken, providing improved movement of the polycarbonate solvent around the waste material. Examples of agitation can include cavitation, vortexing, oscillation, shaking, rotation, stirring, or any combination thereof.

[0049] Applying heat can be used to raise the temperature of the polycarbonate solvent to or below its boiling point, enabling the disclosed method to achieve desired concentration levels, saturation, mixing, and / or dissolution times of the reactive polycarbonate and / or precursor and / or reactive siloxane compound in the polycarbonate solvent. Heat can be applied to cause the polycarbonate solvent to boil and a portion of the polycarbonate solvent to convert to a gaseous form. When heat is applied to convert the polycarbonate solvent to a gaseous form, the vaporized polycarbonate solvent can be contained in a sealed shell or chamber above the recycled solution and / or waste material as waste and / or reactive polycarbonate dissolves in the polycarbonate solvent. Heat can be applied up to the boiling point temperature of the polycarbonate solvent without breaking down one or more polycarbonate chains. Heat can be applied to the polycarbonate solvent at temperatures of about 30°C or higher, about 40°C or higher, or about 50°C or higher. Heat can be applied to the polycarbonate solvent at temperatures of about 160°C or lower, about 120°C or lower, or about 80°C or lower.

[0050] After contacting the polycarbonate solvent and waste material to form a recovery solution, the waste material can be removed from the recovery solution once the desired concentration of waste and / or reactive polycarbonate is reached in the recovery solution. The waste material can be removed by any means sufficient to separate the solid from the liquid. The waste material can be withdrawn from the liquid recovery solution using a suitable container. The waste material can be withdrawn from the recovery solution, subsequently washed with a gaseous polycarbonate solvent, and removed from a shell containing the recovery solution. The waste and / or reactive polycarbonate can have any desired concentration in the polycarbonate solvent, such that the waste polycarbonate can be remediated in subsequent steps using one or more functional compounds. The waste and / or reactive polycarbonate can have a concentration in the polycarbonate solvent equal to or less than a saturation level, said saturation level being equal to or just below the boiling point of the polycarbonate solvent. The waste and / or reactive polycarbonate can have a concentration in the polycarbonate solvent of about 1% by weight or higher, about 5% by weight or higher, or about 10% by weight or higher. Waste polycarbonate may be present in a polycarbonate solvent at a concentration of about 50% by weight or less, about 30% by weight or less, or about 20% by weight or less.

[0051] Any time period during which the polycarbonate solvent, reactive polycarbonate, precursors and / or reactive siloxane compounds and / or waste materials can be contacted sufficiently to dissolve and / or mix the reactive polycarbonate and / or precursors and / or reactive siloxane compounds in the polycarbonate solvent. The amount of time sufficient to dissolve the waste polycarbonate in the polycarbonate solvent to the desired concentration or to saturation may depend on the agitation and / or temperature applied to the waste materials and / or polycarbonate solvent. A time period during which the polycarbonate solvent and waste materials can be contacted may be 10 minutes or longer, approximately 60 minutes or longer, or approximately 90 minutes or longer. A time period during which the polycarbonate solvent and waste materials can be contacted may be 6 hours or less, approximately 4 hours or less, or approximately 3 hours or less. More than one batch of waste materials, reactive polycarbonate and / or precursors and / or reactive siloxane compounds may be contacted with and removed from the polycarbonate solvent until the desired concentration of waste polycarbonate and / or the desired level of flame retardancy is achieved in the recycled solution.

[0052] The recovered solution may be subjected to one or more separation steps configured to remove compounds that may negatively affect the reaction within the recovered solution or compounds remaining in the recovered solution after the reactive polycarbonate has dissolved. The recovered solution may be contacted with one or more scavenging agents configured to precipitate or inert one or more non-polycarbonate compounds or acids or byproducts of the formation of siloxane-modified polycarbonate or reactive siloxane compounds dissolved from the waste material into the polycarbonate solvent. The recovered solution may be contacted with scavenging agents such as adsorbents or absorbents configured to bind with acids. Examples may include one or more of activated carbon, clay, zeolite, polymer adsorbents or absorbents, alkaline washing solutions, buffers, or any combination thereof to remove non-polycarbonate compounds found in the waste material. The scavenging agent may contain any functional group sufficient to bind with free acids, hydroxyl groups, carboxyl groups, readily cleavable polycarbonate chains, or other non-polycarbonate compounds or combinations thereof that are undesirable in the polycarbonate composition, thereby mitigating or avoiding undesirable interactions with the functional groups and / or the waste polycarbonate. Examples of scavenging compounds may include one or more of hydroxides, isocyanates, amines, esters, epoxides, acid anhydrides, carboxylic acids, or any combination thereof. Scavenging agents, adsorbents, and / or absorbent compounds may be removed in liquid or solid form as described herein upon reaction or combination with one or more non-polycarbonate compounds or acids in the recovery solution.

[0053] If non-polycarbonate compounds or acids from waste feedstock are not precipitated by scavenging agents, adsorbents, and / or absorbents, they can be removed by one or more separation techniques configured to remove liquid from liquid (such as solvent extraction, distillation, or any combination thereof). Due to the aforementioned precipitation or movement by scavenging agents, adsorbents, and / or absorbents through multiple perforations in a perforated container, solids may be present in the recovery solution. Any solid non-polycarbonate compounds can be removed from the recovery solution before the addition of functional compounds to avoid undesirable side reactions. Solids can be removed by any known technique sufficient to separate the solids from the liquid. Solids can be removed from the recovery solution by filtration, decantation, precipitation, settling, evaporation, centrifugation, solvent extraction, reverse osmosis, or any combination thereof. Solids can be filtered using a filter with pores having a width smaller than the width of the multiple perforations. Liquids can be removed by any separation technique described herein. Some non-polycarbonate compounds that do not interfere with polycarbonate compounds or functional compounds can remain in the recovery solution until the polycarbonate solvent and siloxane-modified polycarbonate are removed.

[0054] As discussed herein, once the reactive polycarbonate is dissolved in a polycarbonate solvent, the combination of the reactive polycarbonate and the polycarbonate solvent is simultaneously or subsequently contacted with one or more reactive siloxane compounds. The one or more reactive siloxane compounds may contain one or more functional groups, such as methoxy, ethoxy, acetoxy, halide, and / or hydrogen groups, configured to react with one or more reactive groups (i.e., hydroxyl, carboxyl, and / or phenolic groups) of the reactive polycarbonate. The reactive siloxane compounds contain any functional groups that, as discussed herein, impart flame retardancy to the polycarbonate after the reactive siloxane compound is incorporated into the polycarbonate chain and forms a siloxane-modified polycarbonate. The reactive siloxane compound may be added in an amount sufficient to achieve the desired flame retardancy in the siloxane-modified polycarbonate. The desired flame retardancy may be the same as or at least greater than that of the reactive or virgin polycarbonate. The desired flame retardancy can be achieved based on the amount of the added reactive siloxane compound or the reactive siloxane compound present in the siloxane-modified polycarbonate, or combinations thereof. For example, modified and / or reactive polycarbonates can have a UL-94 vertical test rating of V-0 or higher, V-1 or higher, or V-2 or higher at 3.0 mm, 1.6 mm, or 1.0 mm.

[0055] Before or after contact with reactive polycarbonate and reactive siloxane compounds, the recycled solution may be contacted with one or more functional compounds configured to adjust the molecular weight of reactive and / or siloxane-modified polycarbonate. One or more functional compounds and / or precursors and / or reactive siloxane compounds may terminate, extend, or branch the chains of reactive and / or siloxane-modified polycarbonate to have increased molecular weight and / or properties and reduced hydroxyl and / or carboxyl groups. One or more functional compounds and / or precursors and / or reactive siloxane compounds may increase the number-average and / or weight-average molecular weight of the polycarbonate. The weight-average and / or number-average molecular weight may increase by a certain percentage relative to the number-average and / or weight-average molecular weight of the waste and / or reactive polycarbonate prior to the addition of one or more functional compounds and / or precursors and / or reactive siloxane compounds. The percentage increase may be about 5% or more, 20% or more, or about 40% or more. The percentage increase may be about 100% or less, about 75% or less, or about 50% or less. Siloxane-modified polycarbonate can have a greater number-average and / or weight-average molecular weight than waste and / or reactive polycarbonate. The weight-average molecular weight of siloxane-modified polycarbonate relative to waste polycarbonate can be about 10 kg / mol or greater, about 30 kg / mol or greater, or about 50 kg / mol or greater. The weight-average molecular weight of siloxane-modified polycarbonate relative to waste polycarbonate can be about 70 kg / mol or greater, about 90 kg / mol or greater, or about 100 kg / mol or greater. The number-average molecular weight of siloxane-modified polycarbonate relative to waste polycarbonate can be about 3 kg / mol or greater, about 10 kg / mol or greater, or about 20 kg / mol or greater. The number-average molecular weight of siloxane-modified polycarbonate relative to waste polycarbonate can be about 30 kg / mol or greater, about 40 kg / mol or greater, or about 50 kg / mol or greater. The molecular weights described in this disclosure were obtained using narrow-band polystyrene standards via gel permeation chromatography. <1.2) and a wide range of polycarbonate standards ( >1.5) to determine. After adding one or more functional compounds and / or precursors and / or reactive siloxane compounds to the recovery solution, siloxane-modified polycarbonate can have a melt flow rate sufficient for downstream processes and a mass similar to that of virgin polycarbonate. The melt flow rate can be similar to or substantially the same as that of virgin polycarbonate. The melt flow rate of siloxane-modified polycarbonate can be greater than or less than that of waste polycarbonate due to the modified molecular weight resulting from the addition of one or more functional compounds. The melt flow rate of siloxane-modified polycarbonate can be about 1 g / 10 min or higher, about 5 g / 10 min or higher, or about 20 g / 10 min or higher. The melt flow rate of siloxane-modified polycarbonate can be about 80 g / 10 min or lower, about 60 g / 10 min or lower, or about 40 g / 10 min or lower. The melt flow rate was determined by measuring the number of grams (g / 10 min) passed through a standard die (2.095 x 8 mm) for 10 minutes, as determined according to ISO 1133 at 300°C under a load of 1.2 kg.

[0056] After the functional compound and / or precursor and / or reactive siloxane compound are added to the recovery solution, hydroxyl and / or carboxyl groups can be present in sufficiently low amounts to reduce or avoid chain cleavage in the polycarbonate. After the functional compound and / or precursor and / or reactive siloxane compound are added to the recovery solution, the functional compound can react with the hydroxyl and / or carboxyl groups such that the recovery solution is free of or substantially free of (e.g., 0.1 wt%, 0.01 wt%, or 0.01 wt% or less) hydroxyl and / or carboxyl groups. One or more functional compounds and / or precursors and / or reactive siloxane compounds can reduce the amount of free hydroxyl and / or carboxyl groups by 50 mol% or more, 70 mol% or more, or 90 mol% or more. One or more functional compounds and / or precursors and / or reactive siloxane compounds can reduce the amount of free hydroxyl and / or carboxyl groups by 95 mol% or more, 98 mol% or more, or 99 mol% or more. The molar amount of hydroxyl and / or carboxyl groups present in the recovery solution may be reduced due to the molar amount of groups in the functional compound and / or precursor and / or reactive siloxane compound configured to react with hydroxyl and / or carboxyl groups.

[0057] After the formation of siloxane-modified polycarbonate, the recovered solution can be subjected to steps of recovering and / or separating the polycarbonate solvent and / or the siloxane-modified polycarbonate. The polycarbonate solvent and the siloxane-modified polycarbonate can be removed simultaneously or sequentially, separately. The recovered solution can be subjected to process steps that simultaneously separate the polycarbonate solvent and the siloxane-modified polycarbonate, allowing the siloxane-modified polycarbonate to be used in downstream processes, and the polycarbonate solvent to be reused via recycling to recover additional waste polycarbonate. The recovered solution can be subjected to any technique sufficient to separate the two components in the liquid state. The recovered solution can be subjected to one or more of the following: devolatileization, centrifugation, filtration, distillation, or any combination thereof, to separate the siloxane-modified polycarbonate and the polycarbonate solvent. The remaining compounds after the removal of the polycarbonate solvent and the siloxane-modified polycarbonate can be disposed of or subjected to further separation steps to recover desired compounds and recycle them. The non-solvent can be contacted with the recovery solution to precipitate the siloxane-modified polycarbonate from the polycarbonate solvent in a form free of or substantially free of impurities, or in a form that can withstand further separation techniques. The non-solvent may include one or more compounds immiscible with the polycarbonate solvent, such as water, aliphatic hydrocarbons, alcohols, acetonitrile, acetone, or any combination thereof.

[0058] Polycarbonate solvents can be recycled into new, untreated waste feedstock to recover additional waste polycarbonate, restart the process, and avoid undesirable disposal or loss of the polycarbonate solvent. The polycarbonate solvent can be separated from the recovered solution and moved back to the reservoir or waste feedstock via one or more recycling paths extending between chambers. Before being recycled back to contact with the waste feedstock, the polycarbonate solvent can undergo one or more separation steps to remove undesirable impurities. The polycarbonate solvent can be subjected to drying, centrifugation, filtration, distillation, or any combination thereof.

[0059] Before contacting waste materials (including one or more reactive polycarbonates) with one or more polycarbonate solvents or solvent systems, the waste materials may be subjected to one or more pretreatment steps to separate one or more non-polycarbonate compounds from the waste materials, to recover desired compounds and / or avoid undesirable reactions in the recovered materials. The waste materials may be subjected to any pretreatment step configured to remove one or more non-polycarbonate compounds or to prepare waste materials for more efficient extraction of waste polycarbonates. The waste materials may be structurally modified to expose the surface area of ​​components in the waste materials and / or to prepare waste materials for downstream processing steps, which may be done by crushing, grinding, pressing, disassembling, sorting, or any combination thereof. The waste materials may be treated to remove one or more non-polycarbonate compounds, such as inorganic compounds, non-polycarbonate polymers (e.g., polystyrene, styrene-acrylonitrile resin, acrylonitrile-butadiene-styrene, high-impact polystyrene, polymethyl methacrylate, other polymers typically blended with polycarbonates, etc.), small organic molecules, or any combination thereof. Waste materials in the pretreatment step can be subjected to melting, magnetic field, density separation, freezing, agglomeration, washing, chemical removal of adhesives, selective dissolution of other polymers, drying, heating, cooling, or any combination thereof.

[0060] The above steps can be performed in the same chamber or in a series of chambers. Contacting the polycarbonate solvent and waste feedstock can be done in the first chamber; contacting the recovered solution with one or more functional compounds and / or precursors and / or reactive siloxane compounds can be done in the second chamber; and the recovery and / or separation of the polycarbonate solvent and siloxane-modified polycarbonate can be done in the third chamber. Performing the above steps in a series of chambers can mitigate side reactions when adding functional compounds or reactive / precursor siloxane compounds, or allow for more precise control of the separation steps. All steps can be performed in a one-pot manner in the same chamber, recovering, conditioning / repairing / modifying, and removing polycarbonate in one location. One or more pathways can separate the chambers and, where appropriate, move the recovered solution, waste feedstock, polycarbonate solvent, siloxane-modified polycarbonate, or combinations thereof, from the chamber to the chamber.

[0061] Between each of the above-described process steps, each chamber within the housing may be connected by a path configured to move compounds (such as recycled solutions, waste feedstocks, siloxane-modified polycarbonate, and / or polycarbonate solvents) between chambers. The path may include any device sufficient to move the compounds and / or provide additional processing. The path may include device for separating one or more solid compounds from the recycled solution, such as a filter. The housing may include any number of paths between chambers. The housing may include one or more, two or more, three or more, four or more, or more paths between chambers. Each path may be configured to simply move compounds between chambers, recycle polycarbonate solvents after polycarbonate processing, separate non-polycarbonate and polycarbonate compounds, remove separated non-polycarbonate compounds from the housing, move waste feedstocks into and out of the housing, or any combination thereof. Paths or chambers may be equipped with devices configured to monitor the concentration or properties of compounds present in the path or chamber. The path and / or chamber may be equipped with a concentration sensor, a number-average and / or weight-average molecular weight sensor, an impurity sensor, a phase sensor for detecting solids, gases or liquids, a humidity sensor, a temperature sensor, or any combination thereof.

[0062] The disclosed siloxane-modified polycarbonate compositions can be used to prepare structures containing or comprising them using any known process, such as extrusion, molding, thermoforming, etc. The disclosed siloxane-modified polycarbonate compositions can be molded using methods known in the art. The polycarbonate compositions can be molded into useful molded articles by various means, such as injection molding, overmolding, extrusion, rotational molding, blow molding, and thermoforming, to form a variety of molded articles. Such articles can include thin-walled articles for consumer products (such as mobile phones, MP3 players, computers, laptops, cameras, video recorders, electronic tablets, handheld receivers, kitchen utensils, appliance housings, etc.), such as smart meter housings; electrical connectors and lighting equipment components, decorative items, household appliances, roofs, greenhouses, sunrooms, swimming pool railings, light-emitting diodes (LEDs) and lamp panels, extruded film and sheet articles; electrical components, such as relays; and telecommunications components, such as components for base station terminals. This disclosure further envisions additional manufacturing operations for the said article, such as, but not limited to, molding, in-mold decoration, baking in a paint oven, lamination, and / or thermoforming. The disclosed composition is heated to a temperature at which the composition flows, said temperature may be higher than the glass transition temperature of the polycarbonate in the composition. The glass transition temperature is determined using differential scanning calorimetry. Such temperatures may be above 155°C, above 200°C or higher, or 250°C or higher. Such temperatures may be 400°C or lower, or 300°C or lower. The mold may be heated to facilitate processing, such as to 60°C or higher, 80°C or higher, or 100°C or higher.

[0063] Explanatory Implementation Plan Implementation Scheme 1. A method, the method comprising: a. Contacting one or more reactive polycarbonates having free hydroxyl and / or carboxyl groups with one or more reactive siloxane compounds terminated with one or more methoxy, ethoxy, acetoxy, halide and / or hydrogen groups in a solvent system to form one or more siloxane-modified polycarbonates in a recycled solution, wherein the one or more reactive polycarbonates comprise one or more waste polycarbonates.

[0064] Implementation Scheme 2. The method of Implementation Scheme 1, wherein the one or more reactive polycarbonates comprises, based on the total amount of reactive polycarbonate, about 5% by weight to about 95% by weight of the one or more waste polycarbonates.

[0065] Implementation Scheme 3. The method as described in Implementation Scheme 1 or 2, wherein the free hydroxyl and / or carboxyl groups are located at one or more ends of the reactive polycarbonate.

[0066] Implementation Scheme 4. The method as described in Implementation Scheme 3, wherein the free hydroxyl and / or carboxyl groups are positioned along the backbone of the reactive polycarbonate.

[0067] Implementation Scheme 5. The method of any of the preceding embodiments, wherein the siloxane-modified polycarbonate has a number-average and / or weight-average molecular weight that is at least 5% greater than that of the reactive polycarbonate incorporated into the siloxane-modified polycarbonate.

[0068] Implementation Scheme 6. The method as described in any of the foregoing implementation schemes, the method further comprising: a. Contacting the solvent system with one or more waste materials comprising one or more waste polycarbonates and one or more non-polycarbonate compounds to form the recycled solution; and b. Separate at least some of the one or more non-polycarbonate compounds from the recovered solution.

[0069] Implementation Scheme 7. The method as described in any of the foregoing implementation schemes, the method further comprising: a. Contacting one or more precursor siloxane compounds with water to form the one or more reactive siloxane compounds in the recovered solution; and b. Contact the recovered solution with one or more polycarbonate solvents to form a solvent system in the recovered solution comprising the water and the one or more polycarbonate solvents.

[0070] Implementation Scheme 8. The method as described in any of the foregoing implementation schemes, the method further comprising: a. Contacting the one or more reactive polycarbonates with one or more allyl halides to form one or more vinyl ether-terminated polycarbonates, the one or more vinyl ether-terminated polycarbonates being configured to react with the hydrogen atoms of the one or more reactive siloxane compounds to form the one or more siloxane-modified polycarbonates.

[0071] Implementation Scheme 9. The method of any one of the preceding embodiments, wherein the one or more allyl halides are end-capped with an olefin and a halide, and contain 1 to 100 carbon atoms between the carbons at the halide and the olefin.

[0072] Implementation Scheme 10. The method as described in any of the foregoing implementation schemes, the method further comprising: a. Agitating the recovered solution during the formation of the one or more reactive siloxane compounds or siloxane-modified polycarbonates to mix the solvent system.

[0073] Implementation Scheme 11. The method as described in any of the foregoing implementation schemes, the method further comprising: a. Contacting one or more scavenging agents with the recovery solution to remove acids formed by contacting the one or more reactive polycarbonates with the one or more reactive siloxane compounds.

[0074] Implementation Scheme 12. The method as described in any of the preceding implementation schemes, wherein the one or more cleaning agents comprise alkaline washing solutions, adsorbents, or any combination thereof.

[0075] Implementation Scheme 13. The method of any of the preceding embodiments, wherein the reactive polycarbonate and the reactive siloxane compound are contacted in the presence of a catalyst configured to promote the formation of the siloxane-modified polycarbonate.

[0076] Implementation Scheme 14. The method as described in any of the foregoing implementation schemes, the method further comprising: a. Separate substantially all of the water from the recovered solution and solvent system.

[0077] Implementation Scheme 15. The method as described in any of the preceding embodiments, wherein the step of separating the one or more non-polycarbonate compounds or the water from the recovered solution comprises filtration, decantation, centrifugation, extraction, or any combination thereof.

[0078] Implementation Scheme 16. The method of any of the preceding embodiments, wherein the solvent system comprises at least a polycarbonate solvent configured to dissolve the one or more reactive polycarbonates.

[0079] Implementation Scheme 17. The method as described in any of the preceding implementation schemes, wherein the solvent system further comprises water.

[0080] Implementation Scheme 18. The method of any of the preceding embodiments, wherein the siloxane-modified polycarbonate comprises one or more branched siloxane-polycarbonate copolymers.

[0081] Implementation Scheme 19. The method of any one of the preceding embodiments, wherein the one or more reactive siloxane compounds comprises 1 to 100 siloxane units linked in a chain, the chain being capped with at least one methoxy, ethoxy, acetoxy, halide, and / or hydrogen group.

[0082] Implementation Scheme 20. The method as described in any of the preceding implementation schemes, wherein the one or more precursor siloxane compounds comprise at least two halide atoms at different ends.

[0083] Implementation Scheme 21. The method as described in any of the preceding implementation schemes, wherein the one or more precursor siloxane compounds include monohalosilanes, dihalosilanes, trihalosilanes, and / or tetrahalosilanes.

[0084] Implementation Scheme 22. A polymerizable composition comprising: a. One or more reactive polycarbonates, wherein the one or more reactive polycarbonates have free hydroxyl and / or carboxyl groups along the main chain of the one or more reactive polycarbonates and / or at one or more ends of the one or more reactive polycarbonates, wherein the one or more reactive polycarbonates comprise one or more waste polycarbonates; b. A solvent system comprising one or more polycarbonate solvents and / or water; and c. One or more siloxane modifiers, said one or more siloxane modifiers comprising at least one of the following: i. One or more reactive siloxane compounds terminated with at least one hydrogen and one or more allyl halides; ii. One or more reactive siloxane compounds terminated with at least one methoxy, acetoxy, ethoxy, and / or halide group; or iii. One or more precursor siloxane compounds, said precursor siloxane compounds being configured to form, in water, the reactive siloxane compound being terminated with at least one halide. The one or more reactive polycarbonates and the siloxane modifier are capable of reacting in the solvent system to form one or more siloxane-modified polycarbonates.

[0085] Implementation Scheme 23. The polymerizable composition as described in Implementation Scheme 22, wherein the polymerizable composition further comprises: a. One or more compounds containing hydroxyl and / or carboxyl groups.

[0086] Implementation Scheme 24. The polymerizable composition as described in Implementation Schemes 22-23, wherein the polymerizable composition further comprises: a. One or more catalysts, said catalysts being configured to promote the formation of siloxane-modified polycarbonate.

[0087] Implementation Scheme 25. The polymerizable composition as described in Implementation Schemes 22-24, wherein the reactive polycarbonate further comprises one or more virgin polycarbonates.

[0088] Implementation Scheme 26. A polymer composition comprising: a. One or more siloxane-modified polycarbonates, wherein the one or more siloxane-modified polycarbonates comprise: i. one or more polycarbonate segments; and ii. One or more siloxane segments, said one or more siloxane segments being connected to said one or more polycarbonate segments along the main chain of said one or more polycarbonate segments at oxygen atoms and at the ends of said one or more polycarbonate segments, wherein at least some of said one or more siloxane segments are connected to two or more polycarbonate segments.

[0089] Embodiment 27. The polymer composition of Embodiment 26, wherein the one or more siloxane-modified polycarbonates comprise one or more branched siloxane-polycarbonate copolymers.

[0090] Implementation Scheme 28. The polymer composition of embodiments 26-28, wherein the one or more polycarbonate segments comprise residues of waste polycarbonate.

[0091] Implementation Scheme 29. The polymer composition of embodiments 26-29, wherein the one or more polycarbonate segments comprise at least about 5% by weight to 100% by weight or more of waste polycarbonate residues based on the total amount of the siloxane-modified polycarbonate.

[0092] Implementation Scheme 30. The polymer composition of embodiments 26-30, wherein each of the one or more siloxane segments comprises 2 to 100 siloxane repeating units.

[0093] Implementation Scheme 31. The polymer composition as described in Implementation Schemes 26-31, wherein the polymer composition is substantially free of compounds containing hydroxyl and / or carboxyl groups.

[0094] Example Example 1: The degraded polycarbonate (see Table 1, 10 g) was dissolved in 40 mL of dichloromethane and 0.25 mL of triethylamine was added, followed by 1,2-bis(chlorodimethylsilyl)ethane (180 mg). The reaction mixture was stirred at room temperature for 10 hours. A small sample was taken for analysis prior to post-processing. The solution was washed twice with 0.1 M HCl solution and three times with softened water. After evaporation of the solvent, siloxane-modified polycarbonate was obtained.

[0095] Table 1: Molecular weight distribution of degraded polycarbonate measured by size exclusion chromatography and molecular weight distribution after treatment with 1,2-bis(chlorodimethylsilyl)ethane.

[0096] Example 2: The material produced in Example 1 was heated to 300°C in a melt flow rate apparatus, and samples were taken after 0, 1, 2, and 5 minutes. GPC analysis showed no significant decrease in molecular weight, confirming its high thermal stability.

[0097] Figure 1 GPC analysis of the material after heating it to 300°C.

[0098] Table 2 shows the values ​​for each minute of the GPC analysis.

[0099] Example 3: Comparative Example A PC-containing waste was dissolved in dichloromethane to obtain a 15 wt% solution. Insoluble fractions were removed by coarse filtration through a 100 µm sieve and followed by microfiltration through a 0.6 µm filter cartridge. After solvent removal and drying of the recycled PC, the amount of free phenolic substances was determined (Table 3). Unless otherwise stated, phenolic substances were determined by those techniques described herein in relation to compounds containing hydroxyl and / or carboxyl groups, and are measured and expressed in ppm.

[0100] Example A The PC-containing waste was dissolved in dichloromethane and filtered in a manner similar to that described in Comparative Example A. Then, 1,2-bis(chlorodimethylsilyl)ethane (0.28 wt%) was added together with triethylamine (0.27 wt%). After stirring, the solution was stirred for 12 hours, and the organic fraction was washed with dilute hydrochloric acid solution (0.1 M) and water. The organic fraction was separated, and the solvent was evaporated to obtain polycarbonate. After drying, the free phenolic compounds were determined (Table 3). Unless otherwise stated, phenolic compounds were determined by those techniques described in relation to compounds containing hydroxyl and / or carboxyl groups as described herein, and are measured and expressed in ppm.

[0101] Example B The PC-containing waste was dissolved in dichloromethane and filtered in a manner similar to that described in Comparative Example 3. Then, 1,3-dichloro-1,1,3,3-tetramethyldisiloxane (0.27 wt%) was added together with triethylamine (0.27 wt%). After stirring, the solution was stirred for 12 hours, and the organic fraction was washed with dilute hydrochloric acid solution (0.1 M) and water. The organic fraction was separated, and the solvent was evaporated to obtain polycarbonate. After drying, the free phenolic compounds were determined (Table 3). Unless otherwise stated, phenolic compounds were determined by those techniques described in relation to compounds containing hydroxyl and / or carboxyl groups as described herein, and are measured and expressed in ppm.

[0102] Table 3

Claims

1. A method, the method comprising: a. Contacting one or more reactive polycarbonates having free hydroxyl and / or carboxyl groups with one or more reactive siloxane compounds terminated with one or more acetoxy, methoxy, ethoxy, halide or hydrogen atoms in a solvent system to form one or more siloxane-modified polycarbonates in a recycled solution, wherein the one or more reactive polycarbonates comprise one or more waste polycarbonates.

2. The method of claim 1, wherein the one or more reactive polycarbonates comprises, based on the total amount of reactive polycarbonates, about 5% to about 95% by weight of the one or more waste polycarbonates.

3. The method of claim 1 or 2, wherein the free hydroxyl and / or carboxyl groups are located at one or more ends of the reactive polycarbonate.

4. The method of claim 3, wherein the free hydroxyl and / or carboxyl groups are positioned along the backbone of the reactive polycarbonate.

5. The method of any of the preceding claims, wherein the siloxane-modified polycarbonate has a number-average and / or weight-average molecular weight that is at least 5% greater than that of the reactive polycarbonate incorporated into the siloxane-modified polycarbonate.

6. The method as described in any one of the preceding claims, the method further comprising: a. Contact the solvent system with one or more waste materials containing one or more waste polycarbonates and one or more non-polycarbonate compounds to form the recycled solution; as well as b. Separate at least some of the one or more non-polycarbonate compounds from the recovered solution.

7. The method as described in any one of the preceding claims, the method further comprising: a. Contacting one or more precursor siloxane compounds with water to form the one or more reactive siloxane compounds in the recovered solution; as well as b. Contact the recovered solution with one or more polycarbonate solvents to form a solvent system in the recovered solution comprising the water and the one or more polycarbonate solvents.

8. The method as described in any one of the preceding claims, the method further comprising: a. Contacting the one or more reactive polycarbonates with one or more allyl halides to form one or more vinyl ether-terminated polycarbonates, the one or more vinyl ether-terminated polycarbonates being configured to react with the hydrogen atoms of the one or more reactive siloxane compounds to form the one or more siloxane-modified polycarbonates.

9. The method of any of the preceding claims, wherein the one or more allyl halides are end-capped with an olefin and a halide, and contain 1 to 100 carbon atoms between the carbons at the halide and the olefin.

10. The method as described in any one of the preceding claims, the method further comprising: a. Agitating the recovered solution during the formation of the one or more reactive siloxane compounds or siloxane-modified polycarbonates to mix the solvent system.

11. The method as described in any one of the preceding claims, the method further comprising: a. Contacting one or more scavenging agents with the recovery solution to remove acids formed by contacting the one or more reactive polycarbonates with the one or more reactive siloxane compounds.

12. The method of any of the preceding claims, wherein the one or more cleaning agents comprise alkaline washing solutions, adsorbents, or any combination thereof.

13. The method of any of the preceding claims, wherein the reactive polycarbonate and the reactive siloxane compound are contacted in the presence of a catalyst configured to promote the formation of the siloxane-modified polycarbonate.

14. The method as described in any of the preceding claims, further comprising: a. Separate substantially all of the water from the recovered solution and solvent system.

15. The method of any of the preceding claims, wherein the step of separating the one or more non-polycarbonate compounds or the water from the recovered solution comprises filtration, decantation, centrifugation, extraction or any combination thereof.

16. The method of any of the preceding claims, wherein the solvent system comprises at least a polycarbonate solvent configured to dissolve the one or more reactive polycarbonates.

17. The method of any of the preceding claims, wherein the solvent system further comprises water.

18. The method of any of the preceding claims, wherein the siloxane-modified polycarbonate comprises one or more branched siloxane-polycarbonate copolymers.

19. The method of any one of the preceding claims, wherein the one or more reactive siloxane compounds comprises 1 to 100 siloxane units linked in a chain, the chain being capped with at least one methoxy, ethoxy, acetoxy, halide, and / or hydrogen group.

20. The method of any of the preceding claims, wherein the one or more precursor siloxane compounds comprise at least two halide atoms at different ends.

21. The method of any of the preceding claims, wherein the one or more precursor siloxane compounds comprise monohalosilanes, dihalosilanes, trihalosilanes, and / or tetrahalosilanes.

22. A polymerizable composition comprising: a. One or more reactive polycarbonates, wherein the one or more reactive polycarbonates have free hydroxyl and / or carboxyl groups along the main chain of the one or more reactive polycarbonates and / or at one or more ends of the one or more reactive polycarbonates, wherein the one or more reactive polycarbonates comprise one or more waste polycarbonates; b. A solvent system comprising one or more polycarbonate solvents and / or water; and c. One or more siloxane modifiers, said one or more siloxane modifiers comprising at least one of the following: i. One or more reactive siloxane compounds terminated with at least one hydrogen and one or more allyl halides; ii. One or more reactive siloxane compounds terminated with at least one acetoxy, methoxy, ethoxy, halide, or any combination thereof; or iii. One or more precursor siloxane compounds, said precursor siloxane compounds being configured to form, in water, the reactive siloxane compound being terminated with at least one halide. The one or more reactive polycarbonates and the siloxane modifier are capable of reacting in the solvent system to form one or more siloxane-modified polycarbonates.

23. The polymerizable composition of claim 22, further comprising: a. One or more compounds containing hydroxyl and / or carboxyl groups.

24. The polymerizable composition of claims 22-23, wherein the polymerizable composition further comprises: a. One or more catalysts, said catalysts being configured to promote the formation of siloxane-modified polycarbonate.

25. The polymerizable composition of claims 22-24, wherein the reactive polycarbonate further comprises one or more virgin polycarbonates.

26. A polymer composition comprising: a. One or more siloxane-modified polycarbonates, wherein the one or more siloxane-modified polycarbonates comprise: i. one or more polycarbonate segments; and ii. One or more siloxane segments, said one or more siloxane segments being connected to said one or more polycarbonate segments along the main chain of said one or more polycarbonate segments at oxygen atoms and at the ends of said one or more polycarbonate segments, wherein at least some of said one or more siloxane segments are connected to two or more polycarbonate segments.

27. The polymer composition of claim 26, wherein the one or more siloxane-modified polycarbonates comprise one or more branched siloxane-polycarbonate copolymers.

28. The polymer composition of claims 26-28, wherein the one or more polycarbonate segments comprise residues of waste polycarbonate.

29. The polymer composition of claims 26-29, wherein the one or more polycarbonate segments comprise at least about 5% by weight to 100% by weight or more residues of waste polycarbonate based on the total amount of the siloxane-modified polycarbonate.

30. The polymer composition of claims 26-30, wherein each of the one or more siloxane segments comprises 2 to 100 siloxane repeating units.

31. The polymer composition of claims 26-31, wherein the polymer composition is substantially free of compounds containing hydroxyl and / or carboxyl groups.

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