Copolyester in the detection of Fe 3+ Applications and detection of Fe 3+ Method

Abstract

This invention relates to the field of iron ion detection technology, specifically to a copolyester for detecting Fe. 3+ Applications in [the context of the text]. The copolyester contains structural unit A as shown in formula (I) and structural unit B as shown in formula (II), where R [is used in formula (I)]. 11 Selected from groups containing conjugated structures, R 12 Selected from C2-C50 chain alkylene groups, C4-C40 cyclic alkylene groups, or C4-C20 oxygen-containing heterocyclic groups; in formula (II), R 21 Selected from C2-C50 chain alkylene groups, R 22 The copolymer is selected from C2-C50 chain alkylene groups, C4-C40 cyclic alkylene groups, or C4-C20 oxygen-containing heterocyclic groups. The copolyester used in this invention can sensitively detect the presence of iron ions, and has good application prospects in the detection of iron ions in food, pharmaceuticals, soil, water, etc.

Description

Technical Field

[0001] This invention relates to the field of iron ion detection technology, specifically to a copolyester for detecting Fe. 3+ Applications and detection of Fe 3+ The method. Background Technology

[0002] Iron is an essential trace element for living organisms, participating in various forms of cellular biochemical reactions. In the human body, iron is a crucial component of hemoglobin and myoglobin, both responsible for transporting oxygen to all parts of the body, ensuring normal cellular respiration. Besides oxygen transport, iron also participates in the synthesis of purines and collagen, influencing protein and DNA synthesis and immune function. Both insufficient and excessive iron levels in the human body can negatively impact health. Insufficient iron makes it difficult for the body to produce hemoglobin, leading to decreased hemoglobin levels and even iron-deficiency anemia. Excessive iron can cause tissue inflammation, multi-organ damage, and suppressed hematopoiesis. Iron is widely distributed in nature, especially in drinking water; excessive iron ions can disrupt the ion balance in the body, threatening human health. Therefore, developing organic fluorescent compounds with excellent iron recognition capabilities is of great significance.

[0003] Currently, the detection of Fe 3+ The main methods used are atomic spectroscopy, including inductively coupled plasma atomic emission spectrometry (ICP-AES), atomic absorption spectrometry (AAS), and inductively coupled plasma mass spectrometry (ICP-MS). While these methods offer advantages such as high sensitivity and good selectivity, they also suffer from drawbacks such as being time-consuming, requiring large experimental equipment, and involving complex sample processing, thus limiting their widespread use. In contrast, fluorescence detection methods have attracted attention due to their simplicity and high sensitivity. Therefore, the development of highly sensitive Fe... 3+ Fluorescence detection is particularly important. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of existing technologies, such as time-consuming processes, the need for large-scale experimental equipment, and complex sample processing, and to provide a copolyester for detecting Fe. 3+ In its application, this copolyester can sensitively detect the presence of iron ions through obvious fluorescence quenching.

[0005] To achieve the above objectives, the first aspect of the present invention provides a copolyester for detecting Fe 3+ In its application, the copolyester contains structural unit A as shown in formula (I) and structural unit B as shown in formula (II).

[0006]

[0007] In equation (I), R 11 Selected from groups containing conjugated structures, R 12 Selected from C2-C50 chain alkylene groups, C4-C40 cyclic alkylene groups, or C4-C20 oxygen-containing heterocyclic groups; in formula (II), R 21 Selected from C2-C50 chain alkylene groups, R 22 Selected from C2-C50 chain alkylene groups, C4-C40 cyclic alkylene groups, or C4-C20 oxygen-containing heterocyclic groups.

[0008] The second aspect of the present invention provides a method for detecting Fe 3+ A method comprising: a copolyester solution containing a copolyester and a Fe... 3+ The solution is contacted, and then the fluorescence properties are characterized under ultraviolet light excitation; wherein the copolyester is the copolyester described in the first aspect of the present invention.

[0009] Through the above technical solution, the present invention has at least the following beneficial effects:

[0010] In this invention, the above-mentioned copolyester is used to detect iron ions. It has a significant fluorescence quenching effect on iron ions and can sensitively detect the presence of iron ions. It has good application prospects in the detection of iron ions in food, medicine, soil, water and other substances. Attached Figure Description

[0011] Figure 1 These are the fluorescence spectra of four copolyester solutions of different concentrations in Example 1;

[0012] Figure 2 The fluorescence spectra of the five copolyester solutions containing metal ions in Example 1 at an excitation wavelength of 350 nm are shown.

[0013] Figure 3 In Example 1, a copolyester solution with a concentration of 0.02 g / ml was added with 1×10 -4 mol / L Fe 3+ Fe 3+ Comparison of images of copolyester solutions containing ions under an excitation wavelength of 350 nm;

[0014] Figure 4 This is the 1H NMR spectrum of the copolyester in Example 4;

[0015] Figure 5 This is the hydrogen NMR spectrum of the copolyester in Example 5. Detailed Implementation

[0016] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0017] In this invention, unless otherwise specified, "*" in the structure of this invention refers to a connection site.

[0018] The first aspect of the present invention provides a copolyester for detecting Fe 3+ The application of the copolyester is characterized in that the copolyester contains structural unit A as shown in formula (I) and structural unit B as shown in formula (II).

[0019]

[0020] In equation (I), R 11 Selected from groups containing conjugated structures, R 12 Selected from C2-C50 chain alkylene groups, C4-C40 cyclic alkylene groups, or C4-C20 oxygen-containing heterocyclic groups; in formula (II), R 21 Selected from C2-C50 chain alkylene groups, R 22 Selected from C2-C50 chain alkylene groups, C4-C40 cyclic alkylene groups, or C4-C20 oxygen-containing heterocyclic groups.

[0021] The inventors of this invention discovered in their research that the copolyester in this invention has good selectivity for iron ions, and the presence of iron ions can be sensitively detected through obvious fluorescence quenching, showing good application prospects.

[0022] According to a preferred embodiment of the present invention, in formula (I): R 11 Selected from phenylene or naphthylene, preferably phenylene.

[0023] In this invention, "phenylene" refers to a divalent group formed by benzene losing two H atoms, and "naphthylene" refers to a divalent group formed by naphthalene losing two H atoms.

[0024] In this invention, "C2-C50 chain alkylene" refers to alkylene containing 2-50 carbons, which can be straight-chain or branched. Examples of C2-C50 chain alkylene include C2 chain alkylene (e.g., ethylene), C3 chain alkylene (e.g., n-propylene, isopropylene), C4 chain alkylene (e.g., n-butylene, isobutylene), C6 chain alkylene (e.g., n-hexylene, isohexylene), and C8 chain alkylene (e.g., n-octylene). C12 chain alkylene (e.g., dodecaneene), C16 chain alkylene (e.g., hexadecene), C20 chain alkylene (e.g., eicosene), C30 chain alkylene (e.g., triacontylene), C40 chain alkylene (e.g., fortiethane), C50 chain alkylene (e.g., pentadecene), preferably C2-C20 chain alkylene, more preferably C2-C10 chain alkylene, and even more preferably C2-C6 chain alkylene.

[0025] In this invention, "C4-C40 cyclic alkylene" refers to a divalent group formed by the loss of two H atoms in a cyclic alkane having 4-40 carbon atoms. Its cyclic structure can also have alkyl groups, as long as the total number of carbon atoms is satisfied. It is preferably a C4-C20 cyclic alkylene, and more preferably a C10-C20 cyclic alkylene.

[0026] In this invention, "C4-C20 oxygen-containing heterocyclic group" refers to a group in the cyclic structure of a cyclic alkylene group (C4-C20) defined in this invention in which at least one carbon atom is replaced by an oxygen atom. Preferably, the cyclic structure of the oxygen-containing heterocyclic group contains at least two oxygen atoms, and more preferably, it contains two oxygen atoms.

[0027] According to a preferred embodiment of the present invention, in formula (I): R 12 The group is selected from C2-C20 chain alkylene groups, C4-C20 cyclic alkylene groups or C4-C20 oxygen-containing heterocyclic groups, preferably selected from C2-C6 chain alkylene groups or C6-C10 oxygen-containing heterocyclic groups, and more preferably selected from C6-C10 oxygen-containing heterocyclic groups.

[0028] According to a preferred embodiment of the present invention, in formula (I): the cyclic structure containing oxygen-containing heterocyclic group contains at least two oxygen atoms, preferably two oxygen atoms.

[0029] According to a preferred embodiment of the present invention, in formula (II): R 21 The alkylene compounds are selected from C2-C20, preferably from C2-C10.

[0030] According to a preferred embodiment of the present invention, in formula (II): R 22It is selected from C2-C20 chain alkylene groups, C4-C20 cyclic alkylene groups or C4-C20 oxygen-containing heterocyclic groups, preferably selected from C2-C10 chain alkylene groups.

[0031] According to a preferred embodiment of the present invention, in formula (I), R 12 It has any of the following structures:

[0032]

[0033] In this invention, as long as the purpose of this invention can be achieved, the content of structural unit A and structural unit B in the copolyester is not particularly limited and can be selected within a wide range. According to a preferred embodiment of this invention, the molar ratio of structural unit A to structural unit B is 0.1-9:1, for example, 0.1:1, 0.5:1, 0.8:1, 1:1, 1.2:1, 1.5:1, 2:1, 2.5:1, 3:1, 3.5:1, 4:1, 4.5:1, 5:1, 6:1, 7:1, 8:1 or 9:1, or any range of any two of the above ratios.

[0034] In this invention, the size of the copolyester is not particularly limited as long as the purpose of this invention can be achieved. According to a preferred embodiment of this invention, the intrinsic viscosity of the copolyester is 0.2-2 dL / g, for example, 0.2 dL / g, 0.3 dL / g, 0.4 dL / g, 0.5 dL / g, 0.6 dL / g, 0.7 dL / g, 0.8 dL / g, 0.9 dL / g, 1 dL / g, 1.2 dL / g, 1.5 dL / g, 1.8 dL / g, 2 dL / g, or any range of two of the above values.

[0035] The copolyester in this invention has excellent fluorescence properties. According to a preferred embodiment of this invention, the fluorescence emission wavelength of the copolyester is 300-600nm, and preferably, under 365nm ultraviolet light excitation conditions, the fluorescence intensity of the copolyester is 200,000-800,000 CPS.

[0036] The copolyester of this invention can be prepared by conventional polymerization methods in the art, such as a simple two-step melt copolymerization method. The following preparation method is used as an example to illustrate the advantages of this invention, but should not be construed as a limitation of this invention. According to a preferred embodiment of this invention, the preparation method of the copolyester includes:

[0037] (1) In the presence of catalyst A, compound A of formula (IA) and compound B of formula (IB) undergo a first contact reaction to obtain product 1.

[0038] (2) In the presence of catalyst B, compound C of formula (IIC) and compound D of formula (IID) undergo a second contact reaction to obtain product 2;

[0039] (3) Product 1 and Product 2 undergo a polycondensation reaction;

[0040]

[0041] In equations (IA), (IB), (IIC), and (IID), R 11 R 12 R 21 and R 22 The definition and the above-mentioned R of this invention 11 R 12 R 21 and R 22 The definitions correspond to the same;

[0042] In formula (IB), R 111 Alkyl groups selected from H or C1-C10;

[0043] In formula (IID), R 211 Alkyl groups selected from H or C1-C10.

[0044] As can be understood from the present invention, compound A and compound C can each independently be an aliphatic diol, an alicyclic diol, and a heterocyclic diol. Examples of aliphatic diols include ethylene glycol, butanediol, hexanediol, and octanoic acid. Examples of alicyclic diols include 1,2-cyclohexanediethanol, 1,3-cyclohexanediethanol, 1,4-cyclohexanediethanol, 1,2-cyclopentanol, 1,4-cyclohexanol, 1,2-cycloheptanol, tricyclo[5.2.1.0(2,6)]decanediethanol, and 2,2,4,4-tetramethyl-1,3-cyclobutanediol. Examples of heterocyclic diols include isomannitol, isosorbide dinitrate, and isoisodextrin.

[0045] In this invention, the amounts of compound A and compound B can be selected within a wide range. According to a preferred embodiment of this invention, the molar ratio of compound A to compound B is (1-10):1.

[0046] In this invention, the amounts of compound C and compound D can be selected within a wide range. According to a preferred embodiment of this invention, the molar ratio of compound C to compound D is (1-10):1.

[0047] According to a preferred embodiment of the present invention, the molar ratio of product 1 to product 2 is 0.1-9:1.

[0048] According to the present invention, it is understood that the first contact reaction mainly involves esterification and / or transesterification, and catalyst A is only required to promote the esterification and / or transesterification reactions, that is, catalyst A and catalyst B are each independently selected from esterification catalysts and / or transesterification catalysts.

[0049] The esterification catalyst in this invention can be a conventional esterification catalyst in the art, such as one or more of the following: metal acetylacetone complexes, titanium-based organic compounds, tin-based organic compounds, alkoxy metal compounds, metal carbonates, metal bicarbonates, alkoxides, metal phosphites, inorganic acids, organic acids, tertiary amine compounds, and metal acetates.

[0050] The transesterification catalyst in this invention can be a conventional transesterification catalyst in the art, such as one or more of the following: metal hydrides, metal hydroxides, metal acetylacetone complexes, titanium-based organic compounds, tin-based organic compounds, alkoxy metal compounds, metal carbonates, metal bicarbonates, alkoxides, metal phosphites, inorganic acids, organic acids, tertiary amine compounds, and metal acetates.

[0051] Specifically, in this invention, the following metal acetylacetone complexes can be listed: lithium acetylacetone, potassium acetylacetone, magnesium acetylacetone, zinc acetylacetone, etc.; the following titanium-based organic compounds can be listed: tetraethoxytitanium, tetraisopropyl titanate, tetrabutyl titanate, etc.; the following alkoxides can be listed: lithium methoxide, sodium methoxide, potassium methoxide, etc.; the following metal acetates can be listed: lithium acetate, sodium acetate, potassium acetate, zinc acetate, magnesium acetate, manganese acetate, etc.; the following tin-based organic compounds can be listed: stannous chloride, stannous chloride, etc.; and the following organic acids can be listed: p-toluenesulfonic acid, m-toluenesulfonic acid, benzenesulfonic acid, etc.

[0052] In this invention, there is no particular limitation on the amount of catalyst A. The following ranges are provided as examples and do not represent limitations on this invention. According to a preferred embodiment of this invention, based on the total mass of compound A and compound B, the mass of catalyst A is 0.01-0.8 wt%, for example, 0.01 wt%, 0.04 wt%, 0.06 wt%, 0.1 wt%, 0.12 wt%, 0.15 wt%, 0.2 wt%, 0.3 wt%, 0.4 wt%, 0.5 wt%, 0.6 wt%, 0.7 wt%, or 0.8 wt%.

[0053] In this invention, there is no particular limitation on the amount of catalyst B. The following ranges are provided as examples and do not represent limitations on this invention. According to a preferred embodiment of this invention, based on the total mass of compound C and compound D, the mass of catalyst B is 0.01-0.8 wt%, for example, 0.01 wt%, 0.04 wt%, 0.06 wt%, 0.1 wt%, 0.12 wt%, 0.15 wt%, 0.2 wt%, 0.3 wt%, 0.4 wt%, 0.5 wt%, 0.6 wt%, 0.7 wt%, or 0.8 wt%.

[0054] In this invention, the reaction conditions for the first contact in step (1) are not specifically limited. According to a preferred embodiment of the invention, the conditions for the first contact reaction include: a reaction temperature of 160-180°C; wherein, as those skilled in the art know, small molecules will be generated in the first contact reaction. In order to promote the forward reaction during the first contact reaction, the small molecules will continue to condense and distill out. When no liquid is distilled out of the system, it is taken as the reaction endpoint. The reaction time is generally 5-10 hours; in addition, in order to avoid the influence of air, water vapor, etc. on the reaction, the first contact reaction can be carried out under an inert atmosphere.

[0055] In this invention, the reaction conditions for the second contact in step (2) are not specifically limited. According to a preferred embodiment of the invention, the conditions for the second contact reaction include: a reaction temperature of 160-180°C; wherein, as those skilled in the art know, small molecules will be generated in the second contact reaction. In order to promote the forward reaction during the second contact reaction, the small molecules are continuously condensed and distilled out. When no liquid is distilled out of the system, it is taken as the reaction endpoint. The reaction time is generally 5-10 hours; in addition, in order to avoid the influence of air, water vapor, etc. on the reaction, the first contact reaction can be carried out under an inert atmosphere.

[0056] According to a preferred embodiment of the present invention, the conditions for the polycondensation reaction include: a reaction temperature of 220-280°C, preferably a vacuum degree of less than 200 Pa, and the reaction time of the polycondensation can be selected according to the reaction temperature and the vacuum degree of the reaction, preferably 2-20 hours.

[0057] The second aspect of the present invention provides a method for detecting Fe 3+ A method comprising: a copolyester solution containing a copolyester and a Fe... 3+ The solution is contacted, and then the fluorescence properties are characterized under ultraviolet light excitation; wherein the copolyester is the copolyester described in the first aspect of the present invention.

[0058] In this invention, the copolyester solution containing copolyester exhibits fluorescence under ultraviolet light excitation conditions, which is similar to that containing Fe. 3+When a solution containing copolyester is contacted under ultraviolet light excitation, the presence of iron ions can be sensitively detected through significant fluorescence quenching. This is particularly true for solutions containing copolyester and solutions containing Fe. 3+ There are no restrictions on the contact method between the copolyester-containing solution and the Fe-containing solution, as long as the copolyester-containing solution can contact the Fe-containing solution. 3+ Simply mix the solutions thoroughly.

[0059] In this invention, the copolyester solution containing copolyester refers to a copolyester solution prepared by copolyester and solvent. Preferably, the concentration of the copolyester solution is 0.002-0.2 g / mL. The type of solvent is not particularly limited, as long as it can dissolve the copolyester. In one embodiment, the solvent in the copolyester solution is selected from at least one of trifluoroacetic acid, pentafluoropropionic acid, and hexafluoroisopropanol. In this invention, trifluoroacetic acid is used as an example to illustrate the advantages of the invention, but it does not represent a limitation of the invention.

[0060] According to a preferred embodiment of the present invention, the ultraviolet light excitation conditions include an ultraviolet wavelength of 300-600 nm. In this invention, 350 nm is used as an example to illustrate the advantages of the present invention, but it does not represent a limitation of the present invention.

[0061] In this invention, Fe is contained 3+ The source of the solution is not specifically limited, including but not limited to at least one of wastewater, soil, food and pharmaceuticals.

[0062] In this invention, the solution may contain other metal cations. The copolyester in this invention exhibits excellent specificity for iron ion detection and is not affected by the presence of other metal cations. According to a preferred embodiment of this invention, the Fe-containing... 3+ The solution also contains Ca 2+ Zn 2+ K + and Na + At least one of them.

[0063] According to the present invention, it is understood that when Fe is present 3+ When the solution originates from at least one of soil, food, and pharmaceuticals, the analyte element in the sample is introduced into the test solution in an ionic state in a manner well known to those skilled in the art to form an Fe-containing solution. 3+ The solution.

[0064] According to a preferred embodiment of the present invention, the Fe-containing 3+ Fe in solution 3+ The concentration is not less than 1×10 - 5 mol / L.

[0065] The present invention will be described in detail below through embodiments. In the following embodiments,

[0066] The intrinsic viscosity was determined by the following method: 0.125 g of copolyester was dissolved in 25 mL of a mixed solvent of phenol and 1,1,2,2-tetrachloroethane (mass ratio 1:1) at 25 ± 0.1 °C, and the viscosity was measured using an Uberrod thermostat viscometer.

[0067] The fluorescence emission wavelength and fluorescence intensity were measured using the following method. A HORIBA fluorescence spectrometer was used to characterize the fluorescence emission wavelength and fluorescence intensity of the copolyester. During the experiment, the incident light excitation wavelength was fixed at 350 nm, and the slit size was 5 nm. Solution samples were prepared by dissolving an appropriate amount of copolyester in trifluoroacetic acid solvent and then tested. Solid samples were prepared by pressing the copolyester sample into a film of the same thickness under the same pressure and then testing.

[0068] The detection limit is determined by the concentration at which fluorescence emission cannot be detected.

[0069] Example 1

[0070] 0.5 mol of dimethyl terephthalate, 1 mol of ethylene glycol, and 0.16 g of tetrabutyl titanate were added to a four-necked flask and reacted at 179 °C under a nitrogen atmosphere until no liquid distilled out. The product was poured off while hot and kept for later use to obtain ester 1, the mass of which was m1 (g).

[0071] 0.5 mol succinic acid, 1 mol ethylene glycol, and 0.12 g tetrabutyl titanate were added to a four-necked flask and reacted at 179 °C under a nitrogen atmosphere until no liquid was discharged from the system. The product was poured off while hot for later use, and esterified compound 2 was obtained. Its mass was m2 (g).

[0072] Esterified compound 1 (34 wt% m1(g)) and esterified compound 2 (14 wt% m2(g)) were added to a four-necked flask and polycondensed at 270 °C and 80 Pa to obtain a high molecular weight poly(terephthalic acid-ethylene glycol-succinic acid) copolyester.

[0073] The copolyester has an intrinsic viscosity of 0.6 dL / g, a fluorescence emission wavelength of 410 nm, and a fluorescence intensity of 320,000 CPS.

[0074] The copolyester was dissolved in trifluoroacetic acid to prepare four groups of copolyester solutions with different concentrations. The fluorescence spectra of the four groups of copolyester solutions with different concentrations are shown below. Figure 1 As shown.

[0075] The copolyester was dissolved in trifluoroacetic acid to prepare a copolyester solution with a concentration of 0.02 g / ml. 1×10 -4 mol / L Fe 3+ Ca2+ Zn 2+ K + Na + Five groups of copolyester solutions containing metal ions were obtained by dissolving the above copolyester solution. The fluorescence properties of the five groups of copolyester solutions containing metal ions were characterized at an excitation wavelength of 350 nm. The fluorescence spectra of the five groups of copolyester solutions containing metal ions at an excitation wavelength of 350 nm are shown below. Figure 2 As shown, the results indicate that only concentrations of 1×10 -4 mol / L Fe 3+ It can trigger the quenching of copolyester solutions.

[0076] A 0.02 g / ml copolyester solution was added with 1×10 -4 mol / L Fe 3+ Fe 3+ The image comparison of the copolyester solution containing ions at an excitation wavelength of 350 nm is shown below. Figure 3 As shown, Figure 3 In the image, the left side shows a photograph of a copolyester solution with a concentration of 0.02 g / ml under an excitation wavelength of 350 nm, and the right side shows a photograph containing Fe. 3+ An image of an ionic copolyester solution under an excitation wavelength of 350 nm, obtained by... Figure 3 Instructions for adding Fe 3+ The fluorescence emission phenomenon disappeared in the copolyester solution after ionization.

[0077] Example 2

[0078] 0.5 mol of dimethyl phthalate, 1.1 mol of butanediol, and 0.19 g of manganese acetylacetonate were added to a four-necked flask and reacted at 178 °C under a nitrogen atmosphere until no liquid distilled out. The product was poured off while hot and kept for later use to obtain ester 1, the mass of which was m1 (g).

[0079] 0.5 mol adipic acid, 1.1 mol butanediol, and 0.17 g manganese acetylacetonate were added to a four-necked flask and reacted at 176 °C under a nitrogen atmosphere until no liquid was dispensed from the system. The product was poured off while hot for later use, yielding ester 2, whose mass was m2 (g).

[0080] 22 wt% m1 (g) of esterified compound 1 and 16 wt% m2 (g) of esterified compound 2 were added to a four-necked flask and polycondensed at 275 °C and 12 Pa to obtain a high molecular weight poly(phthalic acid-butanediol-adipic acid) copolyester.

[0081] The copolyester has an intrinsic viscosity of 0.7 dL / g, a fluorescence emission wavelength of 460 nm, and a fluorescence intensity of 400,000 CPS.

[0082] The copolyester was dissolved in trifluoroacetic acid to prepare a copolyester solution with a concentration of 0.002 g / ml. 1×10 -4 mol / L Fe 3+ Ca 2+ Zn 2+ K + Na + Five groups of copolyester solutions containing metal ions were obtained by dissolving the above copolyester solution. The fluorescence properties of the five groups of copolyester solutions containing metal ions were characterized at an excitation wavelength of 350 nm. The results showed that only the solution with a concentration of 1×10⁻⁶ metal ions was effective. -4 mol / L Fe 3+ It can trigger the quenching of copolyester solutions.

[0083] Example 3

[0084] 0.7 mol of dimethyl isophthalate, 1.3 mol of hexanediol, and 0.31 g of lithium acetate were added to a four-necked flask and reacted at 175 °C under a nitrogen atmosphere until no liquid distilled out. The product was poured off while hot and kept for later use to obtain ester 1, the mass of which was m1 (g).

[0085] 0.3 mol of octanoic acid, 0.8 mol of hexanediol, and 0.18 g of lithium acetate were added to a four-necked flask and reacted at 180 °C under a nitrogen atmosphere until no liquid was discharged from the system. The product was poured off while hot and kept for later use to obtain ester 2, the mass of which was m2 (g).

[0086] 24 wt% m1(g) of esterified compound 1 and 17 wt% m2(g) of esterified compound 2 were added to a four-necked flask and polycondensed at 280 °C and 15 Pa to obtain a high molecular weight poly(isophthalic acid-hexanediol-octanedioic acid) copolyester.

[0087] The copolyester has an intrinsic viscosity of 0.65 dL / g, a fluorescence emission wavelength of 490 nm, and a fluorescence intensity of 530,000 CPS.

[0088] The copolyester was dissolved in trifluoroacetic acid to prepare a copolyester concentration of 0.2 g / ml. 1×10 -4 mol / L Fe 3+ Ca 2+ Zn 2+ K + Na + Five groups of copolyester solutions containing metal ions were obtained by dissolving the above copolyester solution. The fluorescence properties of the five groups of copolyester solutions containing metal ions were characterized at an excitation wavelength of 350 nm. The results showed that only the solution with a concentration of 1×10⁻⁶ metal ions was effective. -4 mol / L Fe 3+ It can trigger the quenching of copolyester solutions.

[0089] Example 4

[0090] 0.9 mol terephthalic acid, 2.0 mol butanediol, and 0.31 g zinc acetate were added to a four-necked flask and reacted at 173 °C under a nitrogen atmosphere until no liquid distilled out. The product was poured off while hot and kept for later use to obtain ester 1, the mass of which was m1 (g).

[0091] 0.1 mol succinic acid, 0.2 mol butanediol, and 0.10 g tetrabutyl titanate were added to a four-necked flask and reacted at 170 °C under a nitrogen atmosphere until no liquid was discharged from the system. The product was poured off while hot for later use, and ester 2 was obtained. Its mass was m2 (g).

[0092] 25 wt% m1 (g) of esterified compound 1 and 25 wt% m2 (g) of esterified compound 2 were added to a four-necked flask and polycondensed at 265 °C and 8 Pa to obtain a high molecular weight poly(terephthalic acid-butanediol-succinic acid) copolyester.

[0093] The proton NMR spectrum of the copolyester is as follows: Figure 4 As shown.

[0094] The copolyester has an intrinsic viscosity of 0.8 dL / g, a fluorescence emission wavelength of 420 nm, and a fluorescence intensity of 600,000 CPS.

[0095] The copolyester was dissolved in trifluoroacetic acid to prepare a copolyester solution with a concentration of 0.2 g / ml. 1×10 - 5 mol / L Fe 3+ Ca 2+ Zn 2+ K + Na + Five groups of copolyester solutions containing metal ions were obtained by dissolving the above copolyester solution. The fluorescence properties of the five groups of copolyester solutions containing metal ions were characterized at an excitation wavelength of 350 nm. The results showed that only the solution with a concentration of 1×10⁻⁶ metal ions was effective. -5 mol / L Fe 3+ It can trigger the quenching of copolyester solutions.

[0096] Example 5

[0097] 0.5 mol terephthalic acid, 1.1 mol isosorbide, and 0.11 g tetrabutyl titanate were added to a four-necked flask and reacted at 175 °C under a nitrogen atmosphere until no liquid distilled out. The product was poured off while hot and kept for later use to obtain ester 1, whose mass was m1 (g).

[0098] 0.5 mol succinic acid, 1.2 mol ethylene glycol, and 0.10 g tetrabutyl titanate were added to a four-necked flask and reacted at 175 °C under a nitrogen atmosphere until no liquid was discharged from the system. The product was poured off while hot for later use, and esterified compound 2 was obtained. Its mass was m2 (g).

[0099] 50 wt% m1 (g) of esterified compound 1 and 50 wt% m2 (g) of esterified compound 2 were added to a four-necked flask and polycondensed at 275 °C and 10 Pa to obtain a high molecular weight poly(terephthalic acid-isosorbitol-succinic acid-ethylene glycol) copolyester.

[0100] The proton NMR spectrum of the copolyester is as follows: Figure 5 As shown.

[0101] The copolyester has an intrinsic viscosity of 0.63 dL / g, a fluorescence emission wavelength of 520 nm, and a fluorescence intensity of 620,000 CPS.

[0102] Fluorescent copolyester was dissolved in trifluoroacetic acid to prepare a copolyester solution with a concentration of 0.2 g / ml. 1×10 -5 mol / L Fe 3+ Ca 2+ Zn 2+ K + Na + Five groups of copolyester solutions containing metal ions were obtained by dissolving the above copolyester solution. The fluorescence properties of the five groups of copolyester solutions containing metal ions were characterized at an excitation wavelength of 350 nm. The results showed that only solutions with a concentration of 1×10⁻⁶ metal ions showed fluorescence at a concentration of 1×10⁻⁶ metal ions. -5 mol / L Fe 3+ It can trigger the quenching of copolyester solutions.

[0103] Example 6

[0104] 0.5 mol terephthalic acid, 1.1 mol isosorbide, and 0.11 g tetrabutyl titanate were added to a four-necked flask and reacted at 175 °C under a nitrogen atmosphere until no liquid distilled out. The product was poured off while hot and kept for later use to obtain ester 1, and its mass m1 (g) was weighed.

[0105] 0.5 mol succinic acid, 1.2 mol ethylene glycol, and 0.1 g tetrabutyl titanate were added to a four-necked flask and reacted at 175 °C under a nitrogen atmosphere until no liquid was discharged from the system. The product was poured off while hot and kept for later use to obtain ester 2, and its mass was weighed as m2 (g).

[0106] 10 wt% m1(g) of esterified compound 1 and 100 wt% m2(g) of esterified compound 2 were added to a four-necked flask and polycondensed at 275 °C and 10 Pa to obtain a high molecular weight poly(terephthalic acid-isosorbitol-succinic acid-ethylene glycol) copolyester.

[0107] The copolyester has an intrinsic viscosity of 0.62 dL / g, a fluorescence emission wavelength of 380 nm, and a fluorescence intensity of 300,000 CPS.

[0108] Fluorescent copolyester was dissolved in trifluoroacetic acid to prepare a copolyester solution with a concentration of 0.2 g / ml. 1×10 -2 mol / L Fe 3+ Ca 2+ Zn 2+ K + Na + Five groups of copolyester solutions containing metal ions were obtained by dissolving the above copolyester solution. The fluorescence properties of the five groups of copolyester solutions containing metal ions were characterized at an excitation wavelength of 350 nm. The results showed that only solutions with a concentration of 1×10⁻⁶ metal ions showed good fluorescence performance. -2 mol / L Fe 3+ It can trigger the quenching of copolyester solutions.

[0109] Example 7

[0110] 0.5 mol terephthalic acid, 1.1 mol isosorbide, and 0.11 g tetrabutyl titanate were added to a four-necked flask and reacted at 175 °C under a nitrogen atmosphere until no liquid distilled out. The product was poured off while hot and kept for later use to obtain ester 1, and its mass m1 (g) was weighed.

[0111] 0.5 mol succinic acid, 1.2 mol ethylene glycol, and 0.10 g tetrabutyl titanate were added to a four-necked flask and reacted at 175 °C under a nitrogen atmosphere until no liquid was discharged from the system. The product was poured off while hot for later use, and esterified compound 2 was obtained. Its mass was measured as m2 (g).

[0112] 100 wt% m1 (g) of esterified compound 1 and 10 wt% m2 (g) of esterified compound 2 were added to a four-necked flask and polycondensed at 275 °C and 10 Pa to obtain a high molecular weight poly(terephthalic acid-isosorbitol-succinic acid-ethylene glycol) copolyester.

[0113] The copolyester has an intrinsic viscosity of 0.63 dL / g, a fluorescence emission wavelength of 400 nm, and a fluorescence intensity of 305,000 CPS.

[0114] Fluorescent copolyester was dissolved in trifluoroacetic acid to prepare a copolyester solution with a concentration of 0.2 g / ml. 1×10 -2 mol / L Fe 3+ Ca 2+ Zn 2+ K + Na +Five groups of copolyester solutions containing metal ions were obtained by dissolving the above copolyester solution. The fluorescence properties of the five groups of copolyester solutions containing metal ions were characterized at an excitation wavelength of 350 nm. The results showed that only solutions with a concentration of 1×10⁻⁶ metal ions showed good fluorescence performance. -2 mol / L Fe 3+ It can trigger the quenching of copolyester solutions.

[0115] Example 8

[0116] 0.5 mol of p-naphthalenedicarboxylic acid, 1.1 mol of isosorbide, and 0.11 g of tetrabutyl titanate were added to a four-necked flask and reacted at 175 °C under a nitrogen atmosphere until no liquid distilled out. The product was poured off while hot and kept for later use to obtain ester 1, and its mass m1 (g) was weighed.

[0117] 0.5 mol succinic acid, 1.2 mol ethylene glycol, and 0.10 g tetrabutyl titanate were added to a four-necked flask and reacted at 175 °C under a nitrogen atmosphere until no liquid was discharged from the system. The product was poured off while hot for later use, and esterified compound 2 was obtained. Its mass was measured as m2 (g).

[0118] 50 wt% m1 (g) of esterified compound 1 and 50 wt% m2 (g) of esterified compound 2 were added to a four-necked flask and polycondensed at 275 °C and 10 Pa to obtain a high molecular weight poly(p-naphthalenedicarboxylic acid-isosorbitol-succinic acid-ethylene glycol) copolyester.

[0119] The copolyester has an intrinsic viscosity of 0.63 dL / g, a fluorescence emission wavelength of 405 nm, and a fluorescence intensity of 310,000 CPS.

[0120] Fluorescent copolyester was dissolved in trifluoroacetic acid to prepare a copolyester solution with a concentration of 0.2 g / ml. 1×10 -3 mol / L Fe 3+ Ca 2+ Zn 2+ K + Na + Five groups of copolyester solutions containing metal ions were obtained by dissolving the above copolyester solution. The fluorescence properties of these five copolyester solutions were characterized at an excitation wavelength of 350 nm. The results showed that only solutions with a concentration of 1×10⁻⁶ metal ions exhibited good fluorescence. -3 mol / L Fe 3+ It can trigger the quenching of copolyester solutions.

[0121] The intrinsic viscosity, fluorescence emission wavelength, fluorescence intensity, and effect on Fe of the copolyester in the examples are described. 3+ The detection limits are shown in Table 1.

[0122] Table 1

[0123]

[0124] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A copolyester for detecting Fe 3+ The application of [the technology] is characterized by, The copolyester contains structural unit A as shown in formula (I) and structural unit B as shown in formula (II). In equation (I), R 11 Selected from groups containing conjugated structures, R 12 Selected from C2-C50 chain alkylene groups, C4-C40 cyclic alkylene groups, or C4-C20 oxygen-containing heterocyclic groups; In equation (II), R 21 Selected from C2-C50 chain alkylene groups, R 22 Selected from C2-C50 chain alkylene groups, C4-C40 cyclic alkylene groups, or C4-C20 oxygen-containing heterocyclic groups.

2. The application according to claim 1, characterized in that, In formula (I): R 11 Selected from phenylene or naphthylene; and / or R 12 Selected from C2-C20 chain alkylene groups, C4-C20 cyclic alkylene groups, or C4-C20 oxygen-containing heterocyclic groups; and / or The cyclic structure of an oxygen-containing subheterocyclic group contains at least two oxygen atoms.

3. The application according to claim 2, characterized in that, In formula (I): R 11 Selected from phenylene; and / or R 12 Selected from C2-C6 chain alkylene groups or C6-C10 oxygen-containing heterocyclic groups; and / or The cyclic structure of the oxygen-containing subheterocyclic group contains two oxygen atoms.

4. The application according to claim 3, characterized in that, In formula (I): R 12 Selected from oxygen-containing subheterocyclic groups of C6-C10.

5. The application according to claim 1, characterized in that, In formula (II): R 21 Selected from C2-C20 chain alkylene groups; and / or R 22 Selected from C2-C20 chain alkylene groups, C4-C20 cyclic alkylene groups, or C4-C20 oxygen-containing heterocyclic groups.

6. The application according to claim 1, characterized in that, In formula (II): R 21 Selected from C2-C10 chain alkylene groups; and / or R 22 Selected from C2-C10 chain alkylene groups.

7. The application according to claim 1, characterized in that, The molar ratio of structural unit A to structural unit B is 0.1-9:1; and / or The intrinsic viscosity of the copolyester is 0.2-2 dL / g.

8. The application according to claim 1, characterized in that, The copolyester has a fluorescence emission wavelength of 300-600 nm; and / or Under 365nm ultraviolet light excitation, the fluorescence intensity of the copolyester is 200,000-800,000 CPS.

9. The application according to any one of claims 1-8, characterized in that, The method for preparing the copolyester includes: (1) In the presence of catalyst A, compound A of formula (IA) and compound B of formula (IB) undergo a first contact reaction to obtain product 1. (2) In the presence of catalyst B, compound C of formula (IIC) and compound D of formula (IID) undergo a second contact reaction to obtain product 2; (3) Product 1 and Product 2 undergo a polycondensation reaction; In equations (IA), (IB), (IIC), and (IID), R 11 R 12 R 21 and R 22 The definition and any one of claims 1-9 R 11 R 12 R 21 and R 22 The definitions correspond to the same; In formula (IB), R 111 Alkyl groups selected from H or C1-C10; In formula (IID), R 211 Alkyl groups selected from H or C1-C10.

10. The application according to claim 9, characterized in that, The molar ratio of compound A to compound B is (1-10):1; and / or The molar ratio of compound C to compound D is (1-10):1; and / or The molar ratio of product 1 to product 2 is 0.1-9:

1.

11. The application according to claim 9, characterized in that, Catalyst A and catalyst B are each independently selected from esterification catalysts and / or transesterification catalysts; and / or Based on the total mass of compounds A and B, the mass of catalyst A is 0.01-0.8 wt%; and / or Based on the total mass of compounds C and D, the mass of catalyst B is 0.01-0.8 wt%.

12. The application according to claim 11, characterized in that, The esterification catalyst comprises one or more of the following: metal acetylacetone complexes, titanium-based organic compounds, tin-based organic compounds, alkoxy metal compounds, metal carbonates, metal bicarbonates, alkoxides, metal phosphites, inorganic acids, organic acids, tertiary amine compounds, and metal acetates; and / or The transesterification catalyst comprises one or more of the following: metal hydrides, metal hydroxides, metal acetylacetone complexes, titanium-based organic compounds, tin-based organic compounds, alkoxy metal compounds, metal carbonates, metal bicarbonates, alkoxides, metal phosphites, inorganic acids, organic acids, tertiary amine compounds, and metal acetates.

13. The application according to claim 9, characterized in that, In step (1), the conditions for the first contact reaction include: a reaction temperature of 160-180°C; and / or In step (2), the conditions for the second contact reaction include: a reaction temperature of 160-180°C; and / or In step (3), the conditions for the polycondensation reaction include: a reaction temperature of 220-280℃; and / or a vacuum degree of less than 200Pa; and / or a reaction time of 2-20 hours.

14. A method for detecting Fe 3+ The method is characterized by, The method includes: Copolyester solution containing copolyester and Fe 3+ The solution was contacted, and then the fluorescence properties were characterized under ultraviolet light excitation. The copolyester is any one of the copolyesters described in claims 1-13.

15. The method according to claim 14, characterized in that, The concentration of the copolyester solution is 0.002-0.2 g / mL; and / or The solvent in the copolyester solution is selected from at least one of trifluoroacetic acid, pentafluoropropionic acid, and hexafluoroisopropanol; and / or The conditions for ultraviolet light excitation include an ultraviolet wavelength of 300-600 nm.

16. The method according to claim 14 or 15, characterized in that, The Fe-containing 3+ The source of the solution includes at least one of wastewater, soil, food, and pharmaceuticals; and / or The Fe-containing 3+ The solution also contains Ca 2+ Zn 2+ K + and Na + At least one of them; and / or The Fe-containing 3+ Fe in solution 3+ The concentration is not less than 1×10 -5 mol / L.

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