High-performance fluorescent polycarbonate and preparation method and application thereof

Abstract

The application provides a high-performance fluorescent polycarbonate and a preparation method and application thereof. The fluorescent polycarbonate of the application realizes fluorescent emission depending on the clustering of electron-rich groups such as carbonyl and ester groups. The fluorescent polycarbonate has excitation dependence, and is free of carcinogenic and potentially cytotoxic aromatic hydrocarbons such as perylene and benzopyrene in traditional organic fluorescent materials, and has excellent safety and biocompatibility. The fluorescent polycarbonate has the characteristics of excellent emission intensity and controllable wavelength. The fluorescent polycarbonate also has good mechanical and thermal properties, and can exhibit fluorescent properties and ion selectivity in some solvents. The fluorescent polycarbonate has greatly improved added value in the fields of textiles, agriculture, chemical industry and the like, and provides the possibility for the application of the fluorescent polycarbonate in high-tech scenes such as cell imaging, photoelectric display, biological probes and anti-counterfeiting printing.

Description

Technical Field

[0001] This invention belongs to the field of polymer materials technology, specifically relating to a high-performance fluorescent polycarbonate, its preparation method, and its applications. Background Technology

[0002] Organic fluorescent materials (OFMs) are widely used in chemical sensing, cell imaging, optoelectronic displays, biological probes, petroleum processing, and anti-counterfeiting printing. Traditional OFMs mainly generate fluorescence based on the π-π interaction of conjugated aromatic (hetero)cyclic structures. However, these materials are usually characterized by high toxicity, complex synthesis processes, and high preparation costs, which limits their large-scale production and practical applications in biomedicine.

[0003] In recent years, non-traditional intrinsically luminescent (NTIL) polymers based on cluster-induced emission (CTE) and spatial conjugation (TSC) theories have shown remarkable potential in environmental luminescence and biomedicine due to their excellent structural controllability, simple synthetic routes, low toxicity, and good solubility. However, the emission region of NTIL polymers is mainly concentrated below 500 nm, primarily blue light. Adjusting the emission color and intensity of NTIL polymers is fundamentally important for their applications, but the underlying mechanisms are still incomplete. How to obtain highly efficient green, yellow, and red light through molecular engineering and controlling cluster aggregation states urgently needs to be explored. Therefore, overcoming these shortcomings and synthesizing novel fluorescent polymers with broad emission regions through economical, safe, and environmentally friendly methods, while endowing them with excellent mechanical properties and thermal stability, is of great significance for the practical application and further scientific research of NTIL polymers. Summary of the Invention

[0004] The purpose of this invention is to provide a high-performance fluorescent polycarbonate, its preparation method, and its applications. The fluorescent polycarbonate features high emission intensity and controllable wavelength, as well as good mechanical and thermal properties, and exhibits fluorescence and ion selectivity in certain solvents. This fluorescent polycarbonate significantly enhances the added value of textiles, agriculture, and chemicals, and opens up possibilities for its application in high-tech scenarios such as cell imaging, optoelectronic displays, biological probes, and anti-counterfeiting printing.

[0005] To achieve the above objectives, the technical solution provided by the present invention is as follows:

[0006] The present invention provides a fluorescent polycarbonate, wherein the monomers for preparing the fluorescent polycarbonate include a first monomer and a second monomer; the first monomer is selected from at least one diester; and the second monomer is selected from at least one polyol.

[0007] Preferably, the monomers for preparing the fluorescent polycarbonate further include a third monomer and / or a fourth monomer; the third monomer is selected from at least one dicarboxylic acid containing a conjugated structure and / or at least one diester of a dicarboxylic acid containing a conjugated structure; the fourth monomer is selected from at least one aliphatic linear dicarboxylic acid and / or at least one diester of aliphatic linear dicarboxylic acid.

[0008] The present invention also provides a fluorescent polycarbonate, the fluorescent polycarbonate comprising repeating units represented by formula a;

[0009]

[0010] R2 is defined as described above, and * represents a connection point.

[0011] Preferably, the fluorescent polycarbonate further includes repeating units shown in formula b and / or repeating units shown in formula c;

[0012]

[0013] R2, R3, and R5 are defined as described above, and * indicates a connection point.

[0014] The present invention also provides a fluorescent polycarbonate having the structural formula shown in formula i:

[0015]

[0016] In equation i, R2 is defined as described above, * denotes a connection point, and a is selected from integers between 1 and 500;

[0017] Alternatively, the fluorescent polycarbonate has the structural formula shown in formula ii:

[0018]

[0019] In equation ii, R2 and R3 are defined as described above, * indicates a connection point, a and c are the same or different, and are independent integers selected from 1 to 500;

[0020] Alternatively, the fluorescent polycarbonate has the structural formula shown in formula iii:

[0021]

[0022] In equation iii, R2 and R5 are defined as described above, * indicates a connection point, a and b are the same or different, and are independent integers selected from 1 to 500.

[0023] Alternatively, the fluorescent polycarbonate has the structural formula shown in formula iv:

[0024]

[0025] In equation iv, R2, R3, and R5 are defined as described above, * indicates a connection point, a, b, and c are the same or different, and are independent integers selected from 1 to 500.

[0026] The present invention also provides a method for preparing the above-mentioned fluorescent polycarbonate, the method comprising the following steps:

[0027] (a) Under a nitrogen atmosphere, the first monomer and the second monomer are mixed, the first catalyst is added, and the reaction is carried out to prepare the first prepolymer;

[0028] (b) The first prepolymer is subjected to a polycondensation reaction under vacuum conditions to prepare the fluorescent polycarbonate;

[0029] Alternatively, the method may include the following steps:

[0030] (1) Under a nitrogen atmosphere, the first monomer and the second monomer are mixed, the first catalyst is added, and the reaction is carried out to prepare the first prepolymer;

[0031] (2) Under a nitrogen atmosphere, the third monomer and / or the fourth monomer are mixed with the second monomer, a second catalyst is added, and the reaction is carried out to prepare the second prepolymer.

[0032] (3) The first prepolymer and the second prepolymer are mixed and polycondensation reaction is carried out under vacuum to prepare the fluorescent polycarbonate;

[0033] The present invention also provides the application of the above-mentioned fluorescent polycarbonate in the fields of textiles, agriculture, and chemicals.

[0034] Beneficial effects

[0035] (1) The fluorescent polycarbonate of the present invention achieves fluorescence emission through the clustering effect of electron-rich groups such as carbonyl and ester groups. The fluorescent polycarbonate is excitation-dependent, thus eliminating the limitations of traditional organic fluorescent materials. Aromatic hydrocarbons such as perylene and benzo[a]pyrene, which are carcinogenic and have potential cytotoxicity, exhibit excellent safety and biocompatibility.

[0036] (2) The fluorescent polycarbonate of the present invention can be dissolved in solvents such as dimethyl sulfoxide and trifluoroacetic acid and exhibits fluorescence emission. The polymer solution has different degrees of response to metal ions, especially the extremely sensitive response quenching to ferric ions, which provides the possibility for the detection and visual identification of metal ions.

[0037] (3) The fluorescent polycarbonate of the present invention was prepared by melt polycondensation. The preparation process is simple, the raw materials are environmentally friendly, and the overall cost is low. In addition to functional fluorescent properties, the prepared polycarbonate also has good mechanical and thermal properties, making it an excellent engineering plastic.

[0038] (4) The fluorescent polycarbonate of this invention possesses fluorescent properties, which is of great significance for revealing the mechanism of luminescence in unconventional polymers. The preparation process of this invention is simple, the raw materials are environmentally friendly, and the overall cost is low. The prepared polycarbonate has functionalized fluorescent properties and good mechanical and thermal properties, showing great potential in the fields of textile industry, cell imaging, optoelectronic display, biological probes, and anti-counterfeiting printing. Attached Figure Description

[0039] Figure 1 The fluorescent polycarbonate described in Example 1 1 HNMR spectrum;

[0040] Figure 2 The fluorescence emission spectra of the fluorescent polycarbonate described in Example 1 and the fluorescent polyester described in Example 1-Comparative Examples are shown.

[0041] Figure 3 The fluorescence emission spectra of the fluorescent polycarbonate described in Examples 2 and 11 are shown.

[0042] Figure 4 The fluorescence emission spectrum of the fluorescent polycarbonate solution described in Example 8 in response to metal ions;

[0043] Figure 5 This is a visualization of the response of the fluorescent polycarbonate solution described in Example 8 to metal ions. Detailed Implementation

[0044] Fluorescent polycarbonate

[0045] As mentioned above, the present invention provides a fluorescent polycarbonate, wherein the monomers for preparing the fluorescent polycarbonate include a first monomer and a second monomer;

[0046] The first monomer is selected from at least one diester; the second monomer is selected from at least one polyol.

[0047] According to an embodiment of the present invention, the monomers for preparing the fluorescent polycarbonate further include a third monomer and / or a fourth monomer; the third monomer is selected from at least one dicarboxylic acid containing a conjugated structure and / or at least one diester of a dicarboxylic acid containing a conjugated structure; the fourth monomer is selected from at least one aliphatic linear dicarboxylic acid and / or at least one diester of aliphatic linear dicarboxylic acid.

[0048] <First Monomer>

[0049] According to an embodiment of the present invention, the first monomer is selected from at least one diester having the structural formula shown in Formula 1:

[0050] R1—O—CO—O—R1 Formula 1

[0051] In Formula 1, R1 may be the same or different and is independently selected from alkyl groups containing 1-30 carbon atoms or aryl groups containing 6-30 carbon atoms.

[0052] According to an embodiment of the present invention, in Formula 1, R1 may be the same or different and is independently selected from alkyl groups containing 1-18 carbon atoms or aryl groups containing 6-18 carbon atoms.

[0053] Preferably, in Formula 1, R1 may be the same or different and is independently selected from alkyl groups containing 1-12 carbon atoms or aryl groups containing 6-12 carbon atoms.

[0054] Preferably, in Formula 1, R1 may be the same or different and is independently selected from alkyl groups containing 1-6 carbon atoms or aryl groups containing 6-10 carbon atoms.

[0055] More preferably, in Formula 1, R1 may be the same or different, and are independently selected from alkyl groups containing 1-4 carbon atoms or aryl groups containing 6-8 carbon atoms.

[0056] More preferably, in Formula 1, R1 may be the same or different and is independently selected from one of methyl, ethyl, propyl, butyl, phenyl or tolyl.

[0057] According to an embodiment of the present invention, the first monomer is selected from at least one of dimethyl carbonate, diethyl carbonate, dipropyl carbonate, dibutyl carbonate, and diphenyl carbonate.

[0058] According to an embodiment of the present invention, the first monomer can copolymerize with the second monomer to form a repeating unit as shown below. The repeating unit as shown in formula a is an important source of fluorescence in the fluorescent polycarbonate. The introduction of the repeating unit as shown in formula a formed by copolymerizing the first monomer and the second monomer is beneficial to the clustering of electron-rich groups in the fluorescent polycarbonate, thereby enhancing the fluorescence emission intensity of the fluorescent polycarbonate. At the same time, since the first monomer is safe, environmentally friendly, and inexpensive, this can significantly reduce the preparation cost of the fluorescent polycarbonate while obtaining fluorescent polycarbonate with better performance.

[0059] <Second Monomer>

[0060] According to an embodiment of the present invention, the second monomer is selected from at least one polyol having the structural formula shown in Formula 2:

[0061] HO—R2—OH formula 2

[0062] In Formula 2, R2 is selected from substituted or unsubstituted alkylene groups containing 2-40 carbon atoms, substituted or unsubstituted cycloalkylene groups containing 3-40 carbon atoms, substituted or unsubstituted arylene groups containing 6-40 carbon atoms, substituted or unsubstituted heteroarylene groups containing 4-40 carbon atoms and 1-3 heteroatoms, and substituted or unsubstituted heterocyclic groups containing 3-40 carbon atoms and 1-3 heteroatoms, wherein the heteroatoms are N, O, or S; if substituted, the substituent is an alkyl or hydroxyl group containing 1-10 carbon atoms.

[0063] According to an embodiment of the present invention, in Formula 2, R2 is selected from substituted or unsubstituted alkylene groups containing 2-20 carbon atoms, substituted or unsubstituted cycloalkylene groups containing 3-20 carbon atoms, substituted or unsubstituted arylene groups containing 6-20 carbon atoms, substituted or unsubstituted heteroarylene groups containing 4-20 carbon atoms and 1-3 heteroatoms, and substituted or unsubstituted heterocyclic groups containing 3-20 carbon atoms and 1-3 heteroatoms, wherein the heteroatoms are N, O, or S; if substituted, the substituent is an alkyl or hydroxyl group containing 1-10 carbon atoms.

[0064] Preferably, in Formula 2, R2 is selected from substituted or unsubstituted alkylene groups containing 2-12 carbon atoms, substituted or unsubstituted cycloalkylene groups containing 3-12 carbon atoms, substituted or unsubstituted arylene groups containing 6-12 carbon atoms, substituted or unsubstituted heteroarylene groups containing 4-12 carbon atoms and 1-3 heteroatoms, and substituted or unsubstituted heterocyclic groups containing 3-12 carbon atoms and 1-3 heteroatoms, wherein the heteroatoms are N, O, or S; if substituted, the substituent is an alkyl or hydroxyl group containing 1-8 carbon atoms.

[0065] Preferably, in Formula 2, R2 is selected from substituted or unsubstituted alkylene groups containing 2-6 carbon atoms, substituted or unsubstituted cycloalkylene groups containing 3-6 carbon atoms, substituted or unsubstituted arylene groups containing 6-10 carbon atoms, substituted or unsubstituted heteroarylene groups containing 4-8 carbon atoms and 1-3 heteroatoms, and substituted or unsubstituted heterocyclic groups containing 3-6 carbon atoms and 1-3 heteroatoms, wherein the heteroatoms are N, O, or S; if substituted, the substituent is an alkyl or hydroxyl group containing 1-6 carbon atoms.

[0066] More preferably, in Formula 2, R2 is selected from substituted or unsubstituted alkylene groups containing 2-4 carbon atoms, substituted or unsubstituted cycloalkylene groups containing 4-6 carbon atoms, substituted or unsubstituted arylene groups containing 6-8 carbon atoms, substituted or unsubstituted heteroarylene groups containing 6-8 carbon atoms and 1-2 heteroatoms, and substituted or unsubstituted heterocyclic groups containing 4-6 carbon atoms and 1-2 heteroatoms, wherein the heteroatoms are N, O, or S; if substituted, the substituent is an alkyl or hydroxyl group containing 1-3 carbon atoms.

[0067] More preferably, in Formula 2, R2 is selected from ethylidene, butylidene, cyclohexylene, and 2,5-furandimethylene.

[0068] According to an embodiment of the present invention, the second monomer is selected from 1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 1,6-hexanediol, 1,8-octanediol, and isosorbide. Ismannitol Iso-edulol At least one of tricyclodecanediethanol, 2,5-furandiethanol, 1,4-cyclohexanediethanol, 1,3-cyclohexanediethanol and 1,2-cyclohexanediethanol.

[0069] According to an embodiment of the present invention, the introduction of the second monomer can copolymerize with the first, third, and fourth monomers, and the selection of different second monomers can regulate the physical properties of the fluorescent polycarbonate, such as molecular weight, glass transition temperature, and mechanical properties.

[0070] <Third Monomer>

[0071] According to an embodiment of the present invention, the third monomer is selected from at least one dicarboxylic acid having a conjugated structure as shown in Formula 3 and / or at least one diester of a dicarboxylic acid having a conjugated structure as shown in Formula 4:

[0072] HOOC—R3—COOH Formula 3

[0073] R4OOC—R3—COOR4 4

[0074] In Formula 3, R3 is selected from arylene containing 6-30 carbon atoms or heteroarylene containing 4-30 carbon atoms and 1-3 heteroatoms, wherein the heteroatoms are N, O or S;

[0075] In Formula 4, R3 is selected from arylene containing 6-30 carbon atoms or heteroarylene containing 4-30 carbon atoms and 1-3 heteroatoms, wherein the heteroatoms are N, O or S; R4 may be the same or different and are independently selected from alkyl containing 1-10 carbon atoms or aryl containing 6-30 carbon atoms.

[0076] According to an embodiment of the present invention, in Formula 3, R3 is selected from an aryl group containing 6-18 carbon atoms or a heteroaryl group containing 4-18 carbon atoms and 1-2 heteroatoms, wherein the heteroatoms are N, O or S.

[0077] Preferably, in Formula 3, R3 is selected from arylene containing 6-12 carbon atoms or heteroarylene containing 4-12 carbon atoms and 1-2 heteroatoms, wherein the heteroatoms are N, O or S.

[0078] Preferably, in Formula 3, R3 is selected from an aryl group containing 6-10 carbon atoms or a heteroaryl group containing 4-5 carbon atoms and 1-2 heteroatoms, wherein the heteroatoms are N, O or S.

[0079] More preferably, in Formula 3, R3 is selected from phenyl, naphthalene, or furan.

[0080] According to an embodiment of the present invention, in formula 4, R3 is selected from arylene containing 6-18 carbon atoms or heteroarylene containing 4-18 carbon atoms and 1-2 heteroatoms, wherein the heteroatoms are N, O or S; R4 may be the same or different and are independently selected from alkyl containing 1-8 carbon atoms or aryl containing 6-18 carbon atoms.

[0081] Preferably, in Formula 4, R3 is selected from arylene containing 6-12 carbon atoms or heteroarylene containing 4-12 carbon atoms and 1-2 heteroatoms, wherein the heteroatoms are N, O or S; R4 may be the same or different and are independently selected from alkyl containing 1-6 carbon atoms or aryl containing 6-12 carbon atoms.

[0082] Preferably, in Formula 4, R3 is selected from arylene containing 6-10 carbon atoms or heteroarylene containing 4-5 carbon atoms and 1-2 heteroatoms, wherein the heteroatoms are N, O or S; R4 may be the same or different and are independently selected from alkyl containing 1-3 carbon atoms or aryl containing 6-10 carbon atoms.

[0083] More preferably, in Formula 4, R3 is selected from phenyl, naphthalene or furan; R4 may be the same or different and are independently selected from methyl, ethyl, propyl, butyl, phenyl or tolyl.

[0084] According to an embodiment of the present invention, the third monomer is selected from at least one of terephthalic acid, dimethyl terephthalate, diethyl terephthalate, 1,4-naphthalenedicarboxylic acid, dimethyl 1,4-naphthalenedicarboxylic acid, diethyl 1,4-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, dimethyl 2,6-naphthalenedicarboxylic acid, diethyl 2,6-naphthalenedicarboxylic acid, 2,5-furandicarboxylic acid, dimethyl 2,5-furandicarboxylic acid, phthalic acid, dimethyl phthalate, diethyl phthalate, 4,4'-biphenyldicarboxylic acid, dimethyl biphenyldicarboxylic acid, isophthalic acid, dimethyl isophthalate, and diethyl isophthalate.

[0085] According to an embodiment of the present invention, the first monomer has a strong conjugated system, which can effectively regulate the electron cloud density, thereby affecting the light absorption and emission characteristics of the fluorescent polycarbonate. The introduction of the third monomer can copolymerize with the second monomer to form a repeating unit as shown in formula b (as described below), introducing rigid structures such as aryl or heteroaryl groups into the molecular chain, improving the thermal stability and mechanical properties of the fluorescent polycarbonate, and simultaneously regulating its light absorption and emission characteristics. By controlling the proportion of the third monomer added, the thermodynamic properties of the fluorescent polycarbonate, such as glass transition temperature, tensile strength, and elongation at break, can be adjusted. By selecting different third monomers for polymerization, the band structure, fluorescence intensity, and emission wavelength of the fluorescent polycarbonate can be adjusted.

[0086] <Fourth Monomer>

[0087] According to an embodiment of the present invention, the fourth monomer is selected from at least one aliphatic linear dicarboxylic acid having the structure shown in Formula 5 and / or at least one aliphatic linear dicarboxylic acid diester having the structure shown in Formula 6:

[0088] HOOC—R5—COOH Formula 5

[0089] R6OOC—R5—COOR6 style 6

[0090] In Formula 5, R5 is selected from alkylene groups that are absent or contain 1-30 carbon atoms; in Formula 6, R5 is selected from alkylene groups that are absent or contain 1-30 carbon atoms; R6 may be the same or different and are independently selected from alkyl groups containing 1-10 carbon atoms or aryl groups containing 6-30 carbon atoms.

[0091] According to an embodiment of the present invention, in Formula 5, R5 is selected from alkylene groups that are absent or contain 2-20 carbon atoms.

[0092] Preferably, in Formula 5, R5 is selected from alkylene groups that are absent or contain 2-12 carbon atoms.

[0093] Preferably, in Formula 5, R5 is selected from alkylene groups that are absent or contain 2-8 carbon atoms.

[0094] More preferably, in Formula 5, R5 is selected from alkylene groups that are absent or contain 2-6 carbon atoms.

[0095] More preferably, in Formula 5, R5 is selected from non-existent, ethylene, butylene, hexene, octene, decene, or dodecene.

[0096] According to an embodiment of the present invention, in Formula 6, R5 is selected from alkylene groups that are absent or contain 2-20 carbon atoms; R6 may be the same or different and are independently selected from alkyl groups containing 1-8 carbon atoms or aryl groups containing 6-18 carbon atoms.

[0097] Preferably, in Formula 6, R5 is selected from alkylene groups that are absent or contain 2-12 carbon atoms; R6 may be the same or different and are independently selected from alkyl groups containing 1-6 carbon atoms or aryl groups containing 6-12 carbon atoms.

[0098] Preferably, in Formula 6, R5 is selected from alkylene groups that are absent or contain 2-8 carbon atoms; R6 may be the same or different and are independently selected from alkyl groups containing 1-4 carbon atoms or aryl groups containing 6-10 carbon atoms.

[0099] More preferably, in Formula 6, R5 is selected from alkylene groups that are absent or contain 2-6 carbon atoms; R6 may be the same or different and are independently selected from alkyl groups containing 1-3 carbon atoms or aryl groups containing 6-8 carbon atoms.

[0100] More preferably, in Formula 6, R5 is selected from non-existent, ethylene, butylene, hexene, octylene, decylene, or dodecylene; R6 may be the same or different and are independently selected from methyl, ethyl, propyl, butyl, phenyl, or tolyl.

[0101] According to an embodiment of the present invention, the fourth monomer is selected from at least one of succinic acid, dimethyl succinate, oxalic acid, dimethyl oxalate, adipic acid, dimethyl adipic acid, octanoic acid, dimethyl octanoate, sebacic acid, dimethyl sebacic acid, dodecanoic acid, and dimethyl dodecanoate.

[0102] According to an embodiment of the present invention, the second monomer can copolymerize with the fourth monomer to form a repeating unit as shown in formula c (as described below), thereby improving the flexibility of the fluorescent polycarbonate. By selecting the fourth monomer with different carbon chain lengths, the emission wavelength of the fluorescent polycarbonate can be precisely adjusted. By controlling the addition ratio of the fourth monomer, the fluorescence intensity, glass transition temperature, tensile strength, elongation at break, and other properties of the fluorescent polycarbonate can be controlled.

[0103] <Monomers for the Preparation of Fluorescent Polycarbonate>

[0104] According to an embodiment of the present invention, the monomers for preparing the fluorescent polycarbonate include a first monomer and a second monomer; or, the monomers for preparing the fluorescent polycarbonate include a first monomer, a second monomer, and a third monomer; or, the monomers for preparing the fluorescent polycarbonate include a first monomer, a second monomer, and a fourth monomer; or, the monomers for preparing the fluorescent polycarbonate include a first monomer, a second monomer, a third monomer, and a fourth monomer.

[0105] According to an embodiment of the present invention, the fluorescent polycarbonate is copolymerized from a comonomer comprising a first monomer and a second monomer; or, the fluorescent polycarbonate is copolymerized from a comonomer comprising a first monomer, a second monomer, and a third monomer; or, the fluorescent polycarbonate is copolymerized from a comonomer comprising a first monomer, a second monomer, and a fourth monomer; or, the fluorescent polycarbonate is copolymerized from a comonomer comprising a first monomer, a second monomer, a third monomer, and a fourth monomer.

[0106] According to an embodiment of the present invention, in the fluorescent polycarbonate, the ratio of the sum of the molar amounts of the repeating units formed by the third monomer and the repeating units formed by the fourth monomer to the molar amount of the repeating units formed by the second monomer is 0-0.9:1, for example, 0.1-0.9:1, such as 0:1, 0.1:1, 0.2:1, 0.25:1, 0.3:1, 0.4:1, 0.5:1, 0.6:1, 0.7:1, or 0.8:1. A sum of 0 molar amounts of the repeating units formed by the third monomer and the repeating units formed by the fourth monomer means that neither the third nor the fourth monomer is added to the system.

[0107] According to an embodiment of the present invention, in the fluorescent polycarbonate, the molar ratio of the repeating unit formed by the third monomer to the repeating unit formed by the fourth monomer is 0-10:10-0, for example, 1-9:9-1, such as 0:10, 1:9, 2:8, 3:7, 4:6, 5:5, 6:4, 7:3, 8:2, 9:1, or 10:0. A molar amount of 0 for the repeating unit formed by the third monomer means that no third monomer is added to the system; a molar amount of 0 for the repeating unit formed by the fourth monomer means that no fourth monomer is added to the system.

[0108] According to an embodiment of the present invention, in the fluorescent polycarbonate, the molar ratio of the repeating unit formed by the first monomer and the repeating unit formed by the second monomer is 0.1-1:1, for example, 0.1-0.9:1, such as 0.1:1, 0.2:1, 0.25:1, 0.3:1, 0.4:1, 0.5:1, 0.6:1, 0.7:1, 0.8:1 or 0.9:1.

[0109] Fluorescent polycarbonate

[0110] The present invention also provides a fluorescent polycarbonate, the fluorescent polycarbonate comprising repeating units represented by formula a;

[0111]

[0112] R2 is defined as described above, and * represents a connection point.

[0113] According to an embodiment of the present invention, the fluorescent polycarbonate further includes repeating units shown in formula b and / or repeating units shown in formula c;

[0114]

[0115] R2, R3, and R5 are defined as described above, and * indicates a connection point.

[0116] According to an embodiment of the present invention, based on the total molar amount of the fluorescent polycarbonate, the molar percentage of the repeating unit shown in Formula a is 10-100% (e.g., 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or 100%); the molar percentage of the repeating unit shown in Formula b is 0-90% (e.g., 0%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, or 90%); and the molar percentage of the repeating unit shown in Formula c is 0-90% (e.g., 0%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, or 90%).

[0117] According to an embodiment of the present invention, the repeating unit represented by formula a is an important source of fluorescence for the fluorescent polycarbonate; the introduction of the repeating unit represented by formula a is beneficial to the clustering of electron-rich groups in the fluorescent polycarbonate, thereby enhancing the fluorescence emission intensity of the fluorescent polycarbonate.

[0118] According to an embodiment of the present invention, the introduction of the repeating unit shown in Formula b can improve the thermal stability and mechanical properties of the fluorescent polycarbonate; the proportion of the repeating unit shown in Formula b can adjust the glass transition temperature, tensile strength, elongation at break, band structure, fluorescence intensity and emission wavelength of the fluorescent polycarbonate.

[0119] According to an embodiment of the present invention, the introduction of the repeating unit shown in Formula c can improve the flexibility of the fluorescent polycarbonate; the proportion of the repeating unit shown in Formula c can control the glass transition temperature, tensile strength, elongation at break, fluorescence intensity and emission wavelength of the fluorescent polycarbonate.

[0120] According to an embodiment of the present invention, the repeating unit represented by formula a is derived from the first monomer and the second monomer; preferably, the repeating unit represented by formula a is obtained by copolymerization of the first monomer and the second monomer.

[0121] According to an embodiment of the present invention, the repeating unit shown in formula b is derived from the second monomer and the third monomer; preferably, the repeating unit shown in formula b is obtained by copolymerization of the second monomer and the third monomer.

[0122] According to an embodiment of the present invention, the repeating unit represented by formula c is derived from the second monomer and the fourth monomer; preferably, the repeating unit represented by formula c is obtained by copolymerization of the second monomer and the fourth monomer.

[0123] According to an embodiment of the present invention, the fluorescent polycarbonate is a copolymer formed from the repeating unit of formula a.

[0124] According to an embodiment of the present invention, the fluorescent polycarbonate is a copolymer formed by the repeating unit of formula a, the repeating unit of formula b, and / or the repeating unit of formula c; exemplaryly, the fluorescent polycarbonate is a copolymer formed by the repeating unit of formula a and the repeating unit of formula b; or, the fluorescent polycarbonate is a copolymer formed by the repeating unit of formula a and the repeating unit of formula c; or, the fluorescent polycarbonate is a copolymer formed by the repeating unit of formula a, the repeating unit of formula b, and the repeating unit of formula c.

[0125] The present invention also provides a fluorescent polycarbonate having the structural formula shown in formula i:

[0126]

[0127] In equation i, R2 is defined as described above, * represents the connection point, and a is selected from integers between 1 and 500.

[0128] The present invention also provides a fluorescent polycarbonate having the structural formula shown in formula ii:

[0129]

[0130] In equation ii, R2 and R3 are defined as described above, * indicates a connection point, a and c are the same or different, and are independent integers selected from 1 to 500.

[0131] The present invention also provides a fluorescent polycarbonate having the structural formula shown in formula iii:

[0132]

[0133] In equation iii, R2 and R5 are defined as described above, * indicates a connection point, a and b are the same or different, and are independent integers selected from 1 to 500.

[0134] The present invention also provides a fluorescent polycarbonate having the structural formula shown in formula iv:

[0135]

[0136] In equation iv, R2, R3, and R5 are defined as described above, * indicates a connection point, a, b, and c are the same or different, and are independent integers selected from 1 to 500.

[0137] According to an embodiment of the present invention, a is an integer between 50 and 500, preferably an integer between 100 and 400, more preferably an integer between 200 and 300, and even more preferably an integer between 220 and 260.

[0138] According to an embodiment of the present invention, b is an integer between 50 and 500, preferably an integer between 100 and 400, more preferably an integer between 200 and 300, and even more preferably an integer between 220 and 260.

[0139] According to an embodiment of the present invention, c is an integer between 50 and 500, preferably an integer between 100 and 400, more preferably an integer between 200 and 300, and even more preferably an integer between 220 and 260.

[0140] Fluorescent polycarbonate meets at least one of the following parameters:

[0141] According to an embodiment of the present invention, the fluorescent polycarbonate has a number-average molecular weight of 5000-50000.

[0142] According to an embodiment of the present invention, the fluorescent polycarbonate has a molecular weight distribution of 1.2-4.0.

[0143] According to an embodiment of the present invention, the intrinsic viscosity of the fluorescent polycarbonate is 0.2-2.0 dL / g.

[0144] According to an embodiment of the present invention, the glass transition temperature of the fluorescent polycarbonate is 0-110°C.

[0145] According to an embodiment of the present invention, the initial decomposition temperature of the fluorescent polycarbonate is 280-380°C.

[0146] According to an embodiment of the present invention, the tensile strength of the fluorescent polycarbonate is 10-60 MPa.

[0147] According to an embodiment of the present invention, the fluorescent polycarbonate has an elongation at break of 10-1500%.

[0148] According to an embodiment of the present invention, the fluorescent polycarbonate can emit fluorescence from purple to orange when irradiated with excitation light; wherein the wavelength of the excitation light is 300nm-480nm, for example 365nm, 380nm, 390nm, 420nm, 430nm or 450nm.

[0149] According to an embodiment of the present invention, the fluorescence emission wavelength of the fluorescent polycarbonate is determined to be 350-600 nm by a fluorescence spectrometer; for example, the fluorescence emission wavelength is 360 nm, 380 nm, 400 nm, 410 nm, 430 nm, 450 nm, 480 nm, 525 nm, 530 nm, 570 nm or 590 nm.

[0150] <Preparation method of fluorescent polycarbonate>

[0151] As mentioned above, the present invention also provides a method for preparing the above-mentioned fluorescent polycarbonate, the method comprising the following steps:

[0152] (1) Under a nitrogen atmosphere, the first monomer and the second monomer are mixed, the first catalyst is added, and the reaction is carried out to prepare the first prepolymer;

[0153] (2) Under a nitrogen atmosphere, the third monomer and / or the fourth monomer are mixed with the second monomer, a second catalyst is added, and the reaction is carried out to prepare the second prepolymer.

[0154] (3) The first prepolymer and the second prepolymer are mixed and polycondensation reaction is carried out under vacuum to prepare the fluorescent polycarbonate.

[0155] As mentioned above, the present invention also provides a method for preparing the above-mentioned fluorescent polycarbonate, the method comprising the following steps:

[0156] (a) Under a nitrogen atmosphere, the first monomer and the second monomer are mixed, the first catalyst is added, and the reaction is carried out to prepare the first prepolymer;

[0157] (b) The first prepolymer is subjected to a polycondensation reaction under vacuum conditions to prepare the fluorescent polycarbonate.

[0158] According to an embodiment of the present invention, in step (1) and step (a), the temperature of the reaction is 90-180°C, for example, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C or 180°C; the reaction time is 1-8 hours, for example, 1.5 hours, 2 hours, 3 hours, 4 hours or 5 hours, 6 hours or 7 hours; and the reaction pressure is atmospheric pressure.

[0159] According to an embodiment of the present invention, in steps (1) and (a), the molar ratio of the first monomer to the second monomer (i.e., the feeding molar ratio) is (1-10):1, preferably (1-4):1, for example, 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1 or 10:1.

[0160] According to an embodiment of the present invention, in step (2), the temperature of the reaction is 110-180°C, for example, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C or 180°C; the reaction time is 1-5 hours, for example, 1 hour, 1.5 hours, 2 hours, 3 hours, 4 hours or 5 hours; and the reaction pressure is atmospheric pressure.

[0161] According to an embodiment of the present invention, in step (2), the ratio of the sum of the molar amounts of the third monomer and / or the fourth monomer to the molar amount of the second monomer (i.e., the molar ratio of the feed) is 1:(1-10), preferably 1:(1.2-2.5), for example 1:1, 1:1.2, 1:1.5, 1:1.8, 1:2, 1:2.2, 1:2.4, 1:2.5, 1:2.8, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9 or 1:10.

[0162] According to an embodiment of the present invention, in step (3) and step (b), the temperature of the reaction is 180-240°C, for example, 180°C, 190°C, 200°C, 210°C, 220°C, 230°C or 240°C; the reaction time is 1-8 hours, for example, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours or 7 hours; the reaction pressure is 5-2000 Pa, preferably 5-500 Pa.

[0163] According to an embodiment of the present invention, in step (3), the molar ratio (i.e., the feeding molar ratio) of the first prepolymer and the second prepolymer is (1-9):(9-1), preferably (4-6):(6-4), for example 4:6, 5:5 or 6:4.

[0164] According to an embodiment of the present invention, in steps (1) and (2), the first catalyst and the second catalyst may be the same or different, and are independently selected from at least one of the following: metal hydrides, metal hydroxides, metal oxides, metal acetylacetone complexes, titanium-based organic compounds, tin-based organic compounds, alkoxy metal compounds, metal carbonates, metal bicarbonates, metal phosphites, inorganic acids, organic acids, tertiary amines, metal halides, alkali metal compounds, and alkaline earth metal compounds; preferably, the first catalyst and the second catalyst may be the same or different, and are independently selected from at least one of the following: lithium acetylacetone, potassium acetylacetone, magnesium acetylacetone, zinc acetylacetone, calcium acetylacetone, tetraethoxytitanium, tetraisopropyl titanate, tetrabutyl titanate, lithium carbonate, sodium carbonate, potassium carbonate, lithium methoxide, sodium methoxide, potassium methoxide, lithium acetate, sodium acetate, potassium acetate, zinc acetate, magnesium acetate, and manganese acetate.

[0165] <Applications of the above-mentioned fluorescent polycarbonate>

[0166] The present invention also provides the application of the above-mentioned fluorescent polycarbonate in the fields of textiles, agriculture, and chemicals.

[0167] According to embodiments of the present invention, the fluorescent polycarbonate is used in cell imaging, optoelectronic displays, biological probes, and anti-counterfeiting printing.

[0168] The present invention will be further described in detail below with reference to specific embodiments. It should be understood that the following embodiments are merely illustrative and explanatory of the present invention and should not be construed as limiting the scope of protection of the present invention. All technologies implemented based on the above content of the present invention are covered within the scope of protection intended by the present invention.

[0169] Unless otherwise specified, the experimental methods used in the following examples are conventional methods; unless otherwise specified, the reagents and materials used in the following examples are commercially available.

[0170] The intrinsic viscosity, thermal properties, thermal stability, mechanical properties, and fluorescence properties in the following examples were all measured according to the following methods.

[0171] Intrinsic viscosity: 0.125 g of the copolymer was dissolved in 25 ml of a mixed solution of phenol and 1,1,2,2-tetrachloroethane in a mass ratio of 1:1, and the viscosity was measured at 25 °C using an automated viscometer.

[0172] Thermal properties: measured by a TA-DSC Q2000 differential scanning calorimeter.

[0173] Thermal stability: measured by a PerkinElmer TGA8000 thermogravimetric analyzer.

[0174] Mechanical properties: measured at 25℃ using a universal testing instrument (Instron 1122, UK) according to the national standard method (refer to ISO 527 (2012)).

[0175] Fluorescence properties: The polymer was hot-pressed into a film at 180-230℃, and the material was characterized by selecting an appropriate excitation wavelength using a HORIBA FluoroMax+ fluorescence spectrometer.

[0176] Example 1

[0177] Fluorescent polycarbonate was synthesized using dimethyl furanate, dimethyl succinate, dimethyl carbonate, 1,4-butanediol, and isosorbide as raw materials.

[0178] (1) In a 250ml four-necked flask under normal pressure and nitrogen atmosphere, add 0.5mol isosorbide, 1.25mol dimethyl carbonate and 0.56g lithium methoxide, and carry out transesterification reaction at 110℃ for 7 hours. When the system no longer bleeds out, pour out the reaction product while it is hot and cool it for later use to obtain prepolymer 1. The transesterification rate of the reaction is 88%.

[0179] (2) In a 250ml four-necked flask under normal pressure and nitrogen atmosphere, add 0.3mol dimethyl furanate, 0.2mol dimethyl succinate and 1mol 1,4-butanediol and 0.17g tetrabutyl titanate, and carry out transesterification reaction at 150℃ for 4 hours. When the system no longer effluxes, pour out the reaction product while it is hot, cool it for later use, and obtain prepolymer 2. The transesterification rate of the reaction is 95%.

[0180] (3) In a 250ml four-necked flask, prepolymer 1 and prepolymer 2 were added in a molar ratio of 1:1. The polycondensation reaction was carried out at 210℃ and under a high vacuum of 5-30Pa. Fluorescent polycarbonate was obtained after about 5 hours.

[0181] The fluorescent polycarbonate has an intrinsic viscosity of 1.13 dl / g, a glass transition temperature of 73.4℃, an initial decomposition temperature of 326℃, a tensile strength of 56.2±1.6MPa, an elongation at break of 20±4%, and a maximum fluorescence emission wavelength of 530nm under excitation light of 430nm, exhibiting green fluorescence.

[0182] Example 1 - Comparative Example

[0183] Fluorescent polyester was synthesized using dimethyl furanate, dimethyl succinate, 1,4-butanediol, and isosorbide as raw materials.

[0184] (1) In a 250ml four-necked flask under normal pressure and nitrogen atmosphere, add 0.5mol isosorbide, 0.25mol dimethyl furanate and 0.25mol dimethyl succinate, 0.17g tetrabutyl titanate, and carry out transesterification reaction at 150℃ for 4 hours. When the system no longer effluxes, pour out the reaction product while it is hot, cool it for later use, and obtain prepolymer 1. The transesterification rate of the reaction is 94%.

[0185] (2) In a 250ml four-necked flask under normal pressure and nitrogen atmosphere, add 0.3mol dimethyl furanate, 0.2mol dimethyl succinate and 1mol 1,4-butanediol and 0.17g tetrabutyl titanate, and carry out transesterification reaction at 150℃ for 4 hours. When the system no longer effluxes, pour out the reaction product while it is hot, cool it for later use, and obtain prepolymer 2. The transesterification rate of the reaction is 95%.

[0186] (3) In a 250ml four-necked flask, prepolymer 1 and prepolymer 2 were added in a molar ratio of 1:1. The polycondensation reaction was carried out at 210℃ and under a high vacuum of 5-30Pa. Fluorescent polycarbonate was obtained after about 5 hours.

[0187] The fluorescent polyester has an intrinsic viscosity of 1.18 dl / g, a glass transition temperature of 52.1℃, an initial decomposition temperature of 318℃, a tensile strength of 38.4±2.3 MPa, and an elongation at break of 78±6%. Under excitation light of 430 nm, it exhibits a maximum fluorescence emission wavelength of 519 nm, displaying green fluorescence. Its fluorescence emission wavelength and intensity are both lower than those of Example 1.

[0188] Example 2

[0189] Fluorescent polycarbonate was synthesized from dimethyl furanate, dimethyl succinate, diethyl carbonate, 1,6-hexanediol, and isosorbide.

[0190] (1) In a 250ml four-necked flask under normal pressure and nitrogen atmosphere, add 0.5mol isosorbide, 1.5mol diethyl carbonate and 0.15g lithium hydroxide, and carry out transesterification reaction at 120℃ for 7 hours. When the system no longer bleeds out, pour out the reaction product while it is hot, cool it for later use, and obtain prepolymer 1. The transesterification rate of the reaction is 94%.

[0191] (2) In a 250ml four-necked flask under normal pressure and nitrogen atmosphere, add 0.4mol of dimethyl furanate, 0.1mol of dimethyl succinate and 1mol of 1,6-hexanediol and 0.21g of titanium dioxide. The transesterification reaction is carried out at 160℃ for 4 hours. When the system no longer effluxes, the reaction product is poured out while hot and cooled for later use to obtain prepolymer 2. The transesterification rate of the reaction is 96%.

[0192] (3) In a 250ml four-necked flask, prepolymer 1 and prepolymer 2 were added in a molar ratio of 1:1. The polycondensation reaction was carried out at 220℃ and under a high vacuum of 30-100Pa. Fluorescent polycarbonate was obtained after about 4 hours.

[0193] The fluorescent polycarbonate has an intrinsic viscosity of 0.87 dl / g, a glass transition temperature of 54.8℃, an initial decomposition temperature of 331℃, a tensile strength of 41.1±4.3MPa, an elongation at break of 28±3%, and a maximum fluorescence emission wavelength of 528nm under 450nm excitation light, exhibiting green fluorescence.

[0194] Example 3

[0195] Fluorescent polycarbonate was synthesized from dimethyl furanate, dimethyl dodecanoate, 1,4-butanediol, and dimethyl carbonate.

[0196] (1) In a 250ml four-necked flask under normal pressure and nitrogen atmosphere, add 0.5mol 1,4-butanediol, 1.25mol dimethyl carbonate and 0.32g lithium methoxide, and carry out transesterification reaction at 110℃ for 7 hours. When the system no longer bleeds out, pour out the reaction product while it is hot, cool it for later use, and obtain prepolymer 1. The transesterification rate of the reaction is 92%.

[0197] (2) In a 250ml four-necked flask under normal pressure and nitrogen atmosphere, add 0.3mol dimethyl furanate, 0.2mol dimethyl dodecanoate, 1mol 1,4-butanediol, and 0.2g zinc acetate. The transesterification reaction is carried out at 160℃ for 4 hours. When the system no longer effluents, the reaction product is poured out while hot and cooled for later use to obtain prepolymer 2. The transesterification rate of the reaction is 94%.

[0198] (3) In a 250ml four-necked flask, prepolymer 1 and prepolymer 2 were added in a molar ratio of 2:1. The polycondensation reaction was carried out at 220℃ and under a high vacuum of 30-50Pa. Fluorescent polycarbonate was obtained after about 5 hours.

[0199] The fluorescent polycarbonate has an intrinsic viscosity of 1.01 dl / g, a glass transition temperature of 7.8℃, an initial decomposition temperature of 311℃, a tensile strength of 11.3±0.4MPa, an elongation at break of 523±46%, and a maximum fluorescence emission wavelength of 396nm under excitation light of 365nm, exhibiting blue fluorescence.

[0200] Example 4

[0201] Fluorescent polycarbonate was synthesized from dimethyl furanate, 1,3-butanediol, dimethyl carbonate, and isosorbide.

[0202] (1) In a 250ml four-necked flask under normal pressure and nitrogen atmosphere, add 0.4mol isosorbide, 2mol dimethyl carbonate and 0.21g magnesium acetate, and carry out transesterification reaction at 115℃ for 7 hours. When the system no longer bleeds out, pour out the reaction product while it is hot and cool it for later use to obtain prepolymer 1. The transesterification rate of the reaction is 90%.

[0203] (2) In a 250ml four-necked flask under normal pressure and nitrogen atmosphere, add 0.4mol dimethyl furanate, 0.88mol 1,3-butanediol and 0.13g tetrabutyl titanate, and carry out transesterification reaction at 170℃ for 5 hours. When the system no longer effluxes, pour out the reaction product while it is hot, cool it for later use, and obtain prepolymer 2. The transesterification rate of the reaction is 97%.

[0204] (3) In a 250ml four-necked flask, prepolymer 1 and prepolymer 2 were added in a molar ratio of 1:4. The polycondensation reaction was carried out at 220℃ and under a high vacuum of 10-50Pa. Fluorescent polycarbonate was obtained after about 4 hours.

[0205] The fluorescent polycarbonate has an intrinsic viscosity of 0.99 dl / g, a glass transition temperature of 85.8℃, an initial decomposition temperature of 324℃, a tensile strength of 43.5±2.6MPa, an elongation at break of 10±2%, and a maximum fluorescence emission wavelength of 525nm under excitation light of 365nm, exhibiting green fluorescence.

[0206] Example 5

[0207] Fluorescent polycarbonate was synthesized using dimethyl terephthalate, 1,3-propanediol, dipropyl carbonate, and 1,4-butanediol as raw materials.

[0208] (1) In a 250ml four-necked flask under normal pressure and nitrogen atmosphere, add 0.5mol 1,4-butanediol, 1mol dipropyl carbonate and 0.18g lithium acetylacetonate. The transesterification reaction is carried out at 115℃ for 2 hours. When the system no longer bleeds out, pour out the reaction product while it is hot and cool it for later use to obtain prepolymer 1. The transesterification rate of the reaction is 96%.

[0209] (2) In a 250ml four-necked flask under normal pressure and nitrogen atmosphere, add 0.4mol dimethyl terephthalate, 1.2mol 1,3-propanediol and 0.21g zinc acetate, and carry out transesterification reaction at 185℃ for 4 hours. When the system no longer effluents, pour out the reaction product while it is hot, cool it for later use, and obtain prepolymer 2. The transesterification rate of the reaction is 93%.

[0210] (3) In a 250ml four-necked flask, prepolymer 1 and prepolymer 2 were added in a molar ratio of 3:2. The polycondensation reaction was carried out at 230℃ and under a high vacuum of 5-10Pa. Fluorescent polycarbonate was obtained after about 4 hours.

[0211] The fluorescent polycarbonate has an intrinsic viscosity of 0.97 dl / g, a glass transition temperature of 69.2℃, an initial decomposition temperature of 311.7℃, a tensile strength of 35.2±3.4MPa, an elongation at break of 266±22%, and a maximum fluorescence emission wavelength of 397nm under excitation light of 365nm, exhibiting blue-violet fluorescence.

[0212] Example 6

[0213] Fluorescent polycarbonate was synthesized using 2,6-naphthalenedicarboxylic acid, diphenyl carbonate, and 1,4-butanediol as raw materials.

[0214] (1) In a 250ml four-necked flask under normal pressure and nitrogen atmosphere, add 0.4mol 1,4-butanediol, 0.4mol diphenyl carbonate and 0.56g lithium acetate, and carry out transesterification reaction at 130℃ for 3 hours. When the system no longer bleeds out, pour out the reaction product while it is hot, cool it for later use, and obtain prepolymer 1. The transesterification rate of the reaction is 97%.

[0215] (2) In a 250ml four-necked flask under normal pressure and nitrogen atmosphere, add 0.4mol 2,6-naphthalenedicarboxylic acid, 1.2mol 1,4-butanediol and 0.19g germanium oxide, and carry out transesterification reaction at 190℃ for 5 hours. When the system no longer effluents, pour out the reaction product while it is hot, cool it for later use, and obtain prepolymer 2. The transesterification rate of the reaction is 93%.

[0216] (3) In a 250ml four-necked flask, prepolymer 1 and prepolymer 2 were added in a molar ratio of 2:1. The polycondensation reaction was carried out at 240℃ and under a high vacuum of 5-20Pa. Fluorescent polycarbonate was obtained after about 4 hours.

[0217] The fluorescent polycarbonate has an intrinsic viscosity of 0.81 dl / g, a glass transition temperature of 85.6℃, an initial decomposition temperature of 322.6℃, a tensile strength of 37.2±3.1MPa, an elongation at break of 21±3%, and a maximum fluorescence emission wavelength of 525nm under excitation light of 365nm, exhibiting green fluorescence.

[0218] Example 7

[0219] Fluorescent polycarbonate was synthesized from dimethyl biphenylene, 1,4-butanediol, diphenyl carbonate, and 1,4-cyclohexanediethanol.

[0220] (1) In a 250ml four-necked flask under normal pressure and nitrogen atmosphere, add 0.3mol 1,4-cyclohexanediethanol, 0.36mol diphenyl carbonate and 0.32g potassium bicarbonate, and carry out transesterification reaction at 130℃ for 4 hours. When the system no longer bleeds out, pour out the reaction product while it is hot, cool it for later use, and obtain prepolymer 1. The transesterification rate of the reaction is 95%.

[0221] (2) In a 250ml four-necked flask under normal pressure and nitrogen atmosphere, add 0.3mol dimethyl biphenyl dicarboxylate, 1.2mol 1,4-butanediol and 0.42g tetraethoxytitanium, and carry out transesterification reaction at 180℃ for 5 hours. When the system no longer bleeds out, pour out the reaction product while it is hot, cool it for later use, and obtain prepolymer 2. The transesterification rate of the reaction is 96%.

[0222] (3) In a 250ml four-necked flask, prepolymer 1 and prepolymer 2 were added in a molar ratio of 3:2. The polycondensation reaction was carried out at 230℃ and under a high vacuum of 5-10Pa. Fluorescent polycarbonate was obtained after about 5 hours.

[0223] The fluorescent polycarbonate has an intrinsic viscosity of 0.78 dl / g, a glass transition temperature of 46.3℃, an initial decomposition temperature of 319.4℃, a tensile strength of 26.2±1.9MPa, an elongation at break of 217±8%, and a maximum fluorescence emission wavelength of 570nm under excitation light of 365nm, exhibiting yellow fluorescence.

[0224] Example 8

[0225] Fluorescent polycarbonate was synthesized from dimethyl furanate, dimethyl succinate, 1,4-butanediol, and diphenyl carbonate.

[0226] (1) In a 250ml four-necked flask under normal pressure and nitrogen atmosphere, add 0.4mol 1,4-butanediol, 0.5mol diphenyl carbonate and 0.15g lithium carbonate, and carry out transesterification reaction at 130℃ for 5 hours. When the system no longer bleeds out, pour out the reaction product while it is hot, cool it for later use, and obtain prepolymer 1. The transesterification rate of the reaction is 94%.

[0227] (2) In a 250ml four-necked flask under normal pressure and nitrogen atmosphere, add 0.3mol dimethyl furanate, 0.2mol dimethyl succinate, 1mol 1,4-butanediol and 0.15g tetrabutyl titanate, and carry out transesterification reaction at 180℃ for 5 hours. When the system no longer effluxes, pour out the reaction product while it is hot, cool it for later use, and obtain prepolymer 2. The transesterification rate of the reaction is 96%.

[0228] (3) In a 250ml four-necked flask, prepolymer 1 and prepolymer 2 were added in a molar ratio of 1:1. The polycondensation reaction was carried out at 220℃ and under a high vacuum of 50-100Pa. Fluorescent polycarbonate was obtained after about 5 hours.

[0229] The fluorescent polycarbonate has an intrinsic viscosity of 1.07 dl / g, a glass transition temperature of 32.1℃, an initial decomposition temperature of 322℃, a tensile strength of 13.2±1.1 MPa, and an elongation at break of 96±5%. Under excitation at 365 nm, it exhibits a maximum fluorescence emission wavelength of 510 nm, displaying green fluorescence. A 50 mg / ml solution prepared by dissolving it in dimethyl sulfoxide exhibits a maximum fluorescence emission wavelength of 445 nm under 365 nm excitation, demonstrating a specific quenching response to iron ions.

[0230] Example 9

[0231] Fluorescent polycarbonate was synthesized from tricyclodecanediethanol and dimethyl carbonate.

[0232] (1) In a 250ml four-necked flask under normal pressure and nitrogen atmosphere, add 0.3mol tricyclodecanediethanol, 1.5mol dimethyl carbonate and 0.64g lithium methoxide, and carry out transesterification reaction at 115℃ for 7 hours. When the system no longer bleeds out, pour out the reaction product while it is hot, cool it for later use, and obtain prepolymer 1. The transesterification rate of the reaction is 91%.

[0233] (2) Add prepolymer 1 to a 250ml four-necked flask and carry out polycondensation reaction at 220-230℃ and 30-50Pa high vacuum. After about 4.5 hours, fluorescent polycarbonate is obtained.

[0234] The fluorescent polycarbonate has an intrinsic viscosity of 0.88 dl / g, a glass transition temperature of 62.3℃, an initial decomposition temperature of 317℃, a tensile strength of 41.3±5.7MPa, an elongation at break of 13±4%, and a maximum fluorescence emission wavelength of 407nm under excitation light of 365nm, exhibiting blue fluorescence.

[0235] Example 10

[0236] Fluorescent polycarbonate was synthesized from dimethyl adipate, dipropyl carbonate, 2,5-furandiethanol, and 1,4-butanediol.

[0237] (1) In a 250ml four-necked flask under normal pressure and nitrogen atmosphere, add 0.5mol 1,4-butanediol, 1mol dipropyl carbonate and 0.20g lithium hydroxide. The transesterification reaction is carried out at 120℃ for 3 hours. When the system no longer bleeds out, pour out the reaction product while it is hot and cool it for later use to obtain prepolymer 1. The transesterification rate of the reaction is 96%.

[0238] (2) In a 250ml four-necked flask under normal pressure and nitrogen atmosphere, add 0.4mol dimethyl adipate, 0.8mol 2,5-furandiethanol, and 0.52g trimethyl antimonate. The transesterification reaction is carried out at 160℃ for 2 hours. When the system no longer effluents, the reaction product is poured out while hot and cooled for later use to obtain prepolymer 2. The transesterification rate of the reaction is 98%.

[0239] (3) In a 250ml four-necked flask, prepolymer 1 and prepolymer 2 were added in a molar ratio of 3:1. The polycondensation reaction was carried out at 230℃ and under a high vacuum of 30-50Pa. Fluorescent polycarbonate was obtained after about 3 hours.

[0240] The fluorescent polycarbonate has an intrinsic viscosity of 1.15 dl / g, a glass transition temperature of 51.5℃, an initial decomposition temperature of 326℃, a tensile strength of 38.7±6.3MPa, an elongation at break of 86.9±5%, and a maximum fluorescence emission wavelength of 597nm under excitation light of 425nm, exhibiting yellow fluorescence.

[0241] Example 11

[0242] Fluorescent polycarbonate was synthesized using dimethyl furanate, dimethyl succinate, diethyl carbonate, 1,6-hexanediol, and isosorbide as raw materials. (1) In a 250ml four-necked flask under normal pressure and nitrogen atmosphere, 0.5mol isosorbide, 1.5mol dimethyl carbonate, and 0.15g lithium hydroxide were added. The transesterification reaction was carried out at 120℃ for 7 hours. When the system no longer discharged liquid, the reaction product was poured out while hot and cooled for later use to obtain prepolymer 1. The transesterification rate of the reaction was 94%.

[0243] (2) In a 250ml four-necked flask under normal pressure and nitrogen atmosphere, add 0.2mol dimethyl furanate, 0.3mol dimethyl succinate and 1mol 1,6-hexanediol and 0.17g titanium dioxide, and carry out transesterification reaction at 150℃ for 4 hours. When the system no longer effluents, pour out the reaction product while it is hot, cool it for later use, and obtain prepolymer 2. The transesterification rate of the reaction is 99%.

[0244] (3) In a 250ml four-necked flask, prepolymer 1 and prepolymer 2 were added in a molar ratio of 1:1. The polycondensation reaction was carried out at 220℃ and under a high vacuum of 30-100Pa. Fluorescent polycarbonate was obtained after about 4 hours.

[0245] The fluorescent polycarbonate has an intrinsic viscosity of 1.02 dl / g, a glass transition temperature of 37.7℃, an initial decomposition temperature of 329℃, a tensile strength of 17.2±1.0 MPa, and an elongation at break of 203±24%. Under excitation light of 450 nm, it exhibits a maximum fluorescence emission wavelength of 528 nm, displaying stronger green fluorescence than that of Example 2. That is, for fluorescent polycarbonates with the same composition, the fluorescence intensity can be freely adjusted at the same wavelength by adjusting the relative content of the first and second monomers.

[0246] Figure 1 The fluorescent polycarbonate described in Example 1 1 HNMR spectroscopy; each structure was well assigned and labeled, indicating that the fluorescent polycarbonate was successfully prepared.

[0247] Figure 2 The fluorescence emission spectra of the fluorescent polycarbonate described in Example 1 and the fluorescent polyester described in Comparative Example 1 are shown; from Figure 2 It can be seen that Example 1 exhibits stronger green fluorescence than Example 1-Comparative, and the maximum emission wavelength is more redshifted.

[0248] Figure 3 The fluorescence emission spectra of the fluorescent polycarbonate described in Examples 2 and 11; from Figure 3 As can be seen, Example 11 exhibits stronger green fluorescence than Example 2. That is, for fluorescent polycarbonates with the same composition, the fluorescence intensity can be freely adjusted at the same wavelength by adjusting the relative contents of the third and fourth monomers.

[0249] Figure 4 The fluorescence emission spectrum of the fluorescent polycarbonate solution described in Example 8 in response to metal ions; from Figure 4 As can be seen, in the detection of 11 metal ions, the solution exhibits a specific quenching response to ferric ions.

[0250] Figure 5 This is a visualization of the response of the fluorescent polycarbonate solution to metal ions described in Example 8; as shown. Figure 5 As shown, the fluorescent polycarbonate solution can achieve visual identification of ferric ions.

[0251] The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A fluorescent polycarbonate, wherein, The monomers for preparing the fluorescent polycarbonate include a first monomer and a second monomer; the first monomer is selected from at least one diester; and the second monomer is selected from at least one polyol.

2. The fluorescent polycarbonate according to claim 1, wherein, The first monomer is selected from at least one diester having the structural formula shown in Formula 1: R1—O—CO—O—R1 Formula 1 In Formula 1, R1 may be the same or different and is independently selected from alkyl groups containing 1-30 carbon atoms or aryl groups containing 6-30 carbon atoms. Preferably, in Formula 1, R1 may be the same or different and is independently selected from alkyl groups containing 1-18 carbon atoms or aryl groups containing 6-18 carbon atoms. Preferably, the first monomer is selected from at least one of dimethyl carbonate, diethyl carbonate, dipropyl carbonate, dibutyl carbonate, and diphenyl carbonate. Preferably, the second monomer is selected from at least one polyol having the structural formula shown in Formula 2: HO—R2—OH formula 2 In Formula 2, R2 is selected from substituted or unsubstituted alkylene groups containing 2-40 carbon atoms, substituted or unsubstituted cycloalkylene groups containing 3-40 carbon atoms, substituted or unsubstituted arylene groups containing 6-40 carbon atoms, substituted or unsubstituted heteroarylene groups containing 4-40 carbon atoms and 1-3 heteroatoms, and substituted or unsubstituted heterocyclic groups containing 3-40 carbon atoms and 1-3 heteroatoms, wherein the heteroatoms are N, O, or S; if substituted, the substituent is an alkyl or hydroxyl group containing 1-10 carbon atoms. Preferably, in Formula 2, R2 is selected from substituted or unsubstituted alkylene groups containing 2-20 carbon atoms, substituted or unsubstituted cycloalkylene groups containing 3-20 carbon atoms, substituted or unsubstituted arylene groups containing 6-20 carbon atoms, substituted or unsubstituted heteroarylene groups containing 4-20 carbon atoms and 1-3 heteroatoms, and substituted or unsubstituted heterocyclic groups containing 3-20 carbon atoms and 1-3 heteroatoms, wherein the heteroatoms are N, O, or S; if substituted, the substituent is an alkyl or hydroxyl group containing 1-10 carbon atoms. Preferably, the second monomer is selected from 1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 1,6-hexanediol, 1,8-octanediol, and isosorbide. Ismannitol Iso-edulol At least one of tricyclodecanediethanol, 2,5-furandiethanol, 1,4-cyclohexanediethanol, 1,3-cyclohexanediethanol and 1,2-cyclohexanediethanol.

3. The fluorescent polycarbonate according to claim 1 or 2, wherein, The monomers used to prepare the fluorescent polycarbonate further include a third monomer and / or a fourth monomer; the third monomer is selected from at least one dicarboxylic acid containing a conjugated structure and / or at least one diester of a dicarboxylic acid containing a conjugated structure; the fourth monomer is selected from at least one aliphatic linear dicarboxylic acid and / or at least one diester of an aliphatic linear dicarboxylic acid. Preferably, the third monomer is selected from at least one dicarboxylic acid having a conjugated structure as shown in Formula 3 and / or at least one diester of a dicarboxylic acid having a conjugated structure as shown in Formula 4: HOOC—R3—COOH Formula 3 R4OOC—R3—COOR4 style 4 In Formula 3, R3 is selected from arylene containing 6-30 carbon atoms or heteroarylene containing 4-30 carbon atoms and 1-3 heteroatoms, wherein the heteroatoms are N, O or S; In Formula 4, R3 is selected from arylene containing 6-30 carbon atoms or heteroarylene containing 4-30 carbon atoms and 1-3 heteroatoms, wherein the heteroatoms are N, O or S; R4 may be the same or different and are independently selected from alkyl containing 1-10 carbon atoms or aryl containing 6-30 carbon atoms. Preferably, in Formula 3, R3 is selected from arylene containing 6-18 carbon atoms or heteroarylene containing 4-18 carbon atoms and 1-2 heteroatoms, wherein the heteroatoms are N, O or S. Preferably, in Formula 4, R3 is selected from arylene containing 6-18 carbon atoms or heteroarylene containing 4-18 carbon atoms and 1-2 heteroatoms, wherein the heteroatoms are N, O or S; R4 may be the same or different and are independently selected from alkyl containing 1-8 carbon atoms or aryl containing 6-18 carbon atoms. Preferably, the third monomer is selected from at least one of terephthalic acid, dimethyl terephthalate, diethyl terephthalate, 1,4-naphthalenedicarboxylic acid, dimethyl 1,4-naphthalenedicarboxylic acid, diethyl 1,4-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, dimethyl 2,6-naphthalenedicarboxylic acid, diethyl 2,6-naphthalenedicarboxylic acid, 2,5-furandicarboxylic acid, dimethyl 2,5-furandicarboxylic acid, phthalic acid, dimethyl phthalate, diethyl phthalate, 4,4'-biphenylenediic acid, dimethyl biphenylenediate, isophthalic acid, dimethyl isophthalate, and diethyl isophthalate. Preferably, the fourth monomer is selected from at least one aliphatic linear dicarboxylic acid having the structure shown in Formula 5 and / or at least one aliphatic linear dicarboxylic acid diester having the structure shown in Formula 6: HOOC—R5—COOH Formula 5 R6OOC—R5—COOR6 style 6 In Formula 5, R5 is selected from alkylene groups that are absent or contain 1-30 carbon atoms; in Formula 6, R5 is selected from alkylene groups that are absent or contain 1-30 carbon atoms; R6 may be the same or different and are independently selected from alkyl groups containing 1-10 carbon atoms or aryl groups containing 6-30 carbon atoms. Preferably, in Formula 5, R5 is selected from alkylene groups that are absent or contain 2-20 carbon atoms. Preferably, in Formula 6, R5 is selected from alkylene groups that are absent or contain 2-20 carbon atoms; R6 may be the same or different and are independently selected from alkyl groups containing 1-8 carbon atoms or aryl groups containing 6-18 carbon atoms. Preferably, the fourth monomer is selected from at least one of succinic acid, dimethyl succinate, oxalic acid, dimethyl oxalate, adipic acid, dimethyl adipic acid, octanoic acid, dimethyl octanoate, sebacic acid, dimethyl sebacic acid, dodecanoic acid, and dimethyl dodecanoate.

4. The fluorescent polycarbonate according to any one of claims 1-3, wherein, In the fluorescent polycarbonate, the ratio of the sum of the molar amounts of the repeating units formed by the third monomer and the repeating units formed by the fourth monomer to the molar amount of the repeating units formed by the second monomer is 0-0.9:1; the sum of the molar amounts of the repeating units formed by the third monomer and the repeating units formed by the fourth monomer being 0 means that no third monomer or fourth monomer is added to the system. Preferably, in the fluorescent polycarbonate, the molar ratio of the repeating unit formed by the third monomer to the repeating unit formed by the fourth monomer is 0-10:10-0; the molar amount of the repeating unit formed by the third monomer is 0, which means that no third monomer is added to the system; the molar amount of the repeating unit formed by the fourth monomer is 0, which means that no fourth monomer is added to the system. Preferably, in the fluorescent polycarbonate, the molar ratio of the repeating unit formed by the first monomer to the repeating unit formed by the second monomer is 0.1-1:

1.

5. A fluorescent polycarbonate comprising repeating units represented by formula a; in, R2 is defined as described above, where * indicates a connection point. Preferably, the fluorescent polycarbonate further includes repeating units shown in formula b and / or repeating units shown in formula c; R2, R3, and R5 are defined as described above, and * indicates a connection point. Preferably, based on the total molar amount of the fluorescent polycarbonate, the molar percentage of the repeating unit shown in formula a is 10-100%; the molar percentage of the repeating unit shown in formula b is 0-90%; and the molar percentage of the repeating unit shown in formula c is 0-90%.

6. A fluorescent polycarbonate having the structural formula shown in formula i: In equation i, R2 is defined as described above, * denotes a connection point, and a is selected from integers between 1 and 500; Alternatively, the fluorescent polycarbonate has the structural formula shown in formula ii: In equation ii, R2 and R3 are defined as described above, * indicates a connection point, a and c are the same or different, and are independent integers selected from 1 to 500; Alternatively, the fluorescent polycarbonate has the structural formula shown in formula iii: In equation iii, R2 and R5 are defined as described above, * indicates a connection point, a and b are the same or different, and are independent integers selected from 1 to 500. Alternatively, the fluorescent polycarbonate has the structural formula shown in formula iv: In equation iv, R2, R3, and R5 are defined as described above, * indicates a connection point, a, b, and c are the same or different, and are independent integers selected from 1 to 500.

7. The fluorescent polycarbonate according to any one of claims 1-6, wherein, The fluorescent polycarbonate satisfies at least one of the following parameters: The fluorescent polycarbonate has a number-average molecular weight of 5000-50000; The fluorescent polycarbonate has a molecular weight distribution of 1.2-4.0; The intrinsic viscosity of the fluorescent polycarbonate is 0.2-2.0 dL / g; The glass transition temperature of the fluorescent polycarbonate is 0-110℃; The initial decomposition temperature of the fluorescent polycarbonate is 280-380℃; The tensile strength of the fluorescent polycarbonate is 10-60 MPa; The fluorescent polycarbonate has an elongation at break of 10-1500%; The fluorescent polycarbonate emits fluorescence ranging from purple to orange when irradiated with excitation light; wherein the wavelength of the excitation light is 300nm-480nm. The fluorescence emission wavelength of the fluorescent polycarbonate was determined to be 350-600 nm using a fluorescence spectrometer.

8. A method for preparing the fluorescent polycarbonate according to any one of claims 1-7, the method comprising the following steps: (a) Under a nitrogen atmosphere, the first monomer and the second monomer are mixed, the first catalyst is added, and the reaction is carried out to prepare the first prepolymer; (b) The first prepolymer is subjected to a polycondensation reaction under vacuum conditions to prepare the fluorescent polycarbonate; Alternatively, the method may include the following steps: (1) Under a nitrogen atmosphere, the first monomer and the second monomer are mixed, the first catalyst is added, and the reaction is carried out to prepare the first prepolymer; (2) Under a nitrogen atmosphere, the third monomer and / or the fourth monomer are mixed with the second monomer, a second catalyst is added, and the reaction is carried out to prepare the second prepolymer. (3) The first prepolymer and the second prepolymer are mixed and polycondensation reaction is carried out under vacuum to prepare the fluorescent polycarbonate.

9. The preparation method according to claim 8, wherein in step (1) and step (a), the reaction temperature is 90-180°C; the reaction time is 1-8 hours; and / or, in step (1) and step (a), the molar ratio of the first monomer to the second monomer is (1-10):

1. Preferably, in step (2), the reaction temperature is 110-180℃; the reaction time is 1-5 hours; and / or, in step (2), the ratio of the sum of the molar amounts of the third monomer and / or the fourth monomer to the molar amount of the second monomer is 1:(1-10). Preferably, in step (3) and step (b), the reaction temperature is 180-240°C; the reaction time is 1-8 hours; the reaction pressure is 5-2000 Pa; and / or, in step (3), the molar ratio of the first prepolymer to the second prepolymer is (1-9):(9-1).

10. The application of the fluorescent polycarbonate according to any one of claims 1-7 in the textile, agricultural, and chemical industries. Preferably, the fluorescent polycarbonate is used in cell imaging, optoelectronic displays, biological probes, and anti-counterfeiting printing.

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