A photochromic multi-component copolyester, a photochromic biodegradable polyester film and preparation and application thereof

Abstract

The application discloses a photochromic multi-component copolyester, a photochromic biodegradable polyester film and preparation and application thereof. The copolyester comprises a first repeating unit shown in formula (I) and a second repeating unit shown in formula (II); the molar ratio of the first repeating unit to the second repeating unit is (5-95):(95-5). The application introduces a diaryethene photochromic structural unit and a polylactone segment into a polyester molecular main chain, can synthesize a block or random copolymer as required, cooperatively gives the polyester intrinsic photochromic characteristics and biodegradability, and can precisely control the mechanical properties and degradation rate of the material. The application also provides a photochromic biodegradable polyester film prepared from the polyester, the film has adjustable mechanical properties, fast and stable light response, excellent film-forming property, can realize reversible photochromism and controllable degradation.

Description

Technical Field

[0001] This invention relates to the field of polyester films, and more particularly to a photochromic multi-component copolyester, a photochromic biodegradable polyester film, and their preparation and application. Background Technology

[0002] Photochromic films with biodegradability typically possess environmentally friendly and biocompatible characteristics and have important applications in multiple fields. However, existing technologies provide few implementation examples, and the preparation steps are usually numerous and the raw materials are complex.

[0003] Polyester materials such as polylactic acid and polycaprolactone are biodegradable and important sustainable materials; however, their structures are relatively simple and their functionality is limited. Existing technologies also exist to design functional and intelligent materials based on these materials. This process often requires the addition of suitable raw materials or chemical modification, making the preparation process relatively complex and potentially degrading the material's performance.

[0004] Diarylethylene and azobenzene structural units can be used to construct suitable photochromic materials, both exhibiting similar photoresponse capabilities. Existing azobenzene materials are relatively limited in variety and exhibit poor thermal stability in their photoresponse. Diarylethylene materials, on the other hand, offer a wider variety, faster response, and greater stability, making them more attractive. However, they are typically more expensive, have poor film-forming properties, and exhibit inferior and difficult-to-tunable mechanical properties. Summary of the Invention

[0005] In view of this, this application provides a photochromic multi-component copolyester, a photochromic biodegradable polyester film, and their preparation and application. The polyester prepared in this application can be synthesized into block or random copolymers as needed, with a uniform structure and no phase separation, possessing both intrinsic photochromic properties and biodegradability; the film prepared from it has tunable mechanical properties, rapid and stable light response, and excellent film-forming properties, enabling reversible photochromism and controllable degradation.

[0006] This application provides a photochromic multi-component copolyester, comprising a first repeating unit as shown in formula (I) and a second repeating unit as shown in formula (II):

[0007] Formula (I); Formula (II);

[0008] The molar ratio of the first repeating unit shown in formula (I) to the second repeating unit shown in formula (II) is (5~95):(95~5);

[0009] R1~R4 and R5~R8 can be independently selected from hydrogen, halogen, substituted or unsubstituted C1~C10 alkyl sulfonyl, substituted or unsubstituted C1~C10 alkyl, substituted or unsubstituted C1~C20 alkoxy, substituted or unsubstituted C6~C20 aryl, substituted or unsubstituted C1~C20 heteroaryl, or any two adjacent R1~R4 are fused with the carbon atom of the benzene ring to which they are attached, and / or any two adjacent R5~R8 are fused with the carbon atom of the benzene ring to which they are attached, to form a substituted or unsubstituted C6~C20 fused ring.

[0010] R9, R 10 Each is independently selected from hydrogen, substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C6-C20 aryl; or, R9, R 10 It forms substituted or unsubstituted C5-C20 polycyclic rings with the carbon atoms it is attached to;

[0011] R x For (CR) a R b ) q Where q is an integer from 1 to 10, and R a R b It can be independently selected from hydrogen, substituted or unsubstituted C1 to C10 alkyl groups;

[0012] The substituents are one or more of C1-C6 alkyl groups and C2-C6 alkenyl groups.

[0013] In some specific implementations, R1~R4 and R5~R8 are each independently selected from hydrogen, fluorine, bromine, substituted or unsubstituted C1~C6 alkylsulfonyl, substituted or unsubstituted C1~C6 alkyl, substituted or unsubstituted C1~C10 alkoxy, C2~C6 carbamate, substituted or unsubstituted C6~C12 aryl, substituted or unsubstituted C4~C10 heteroaryl; or, any two adjacent R1~R4 are fused with the carbon atom of the benzene ring to which they are attached, and / or any two adjacent R5~R8 are fused with the carbon atom of the benzene ring to which they are attached, to form one of the substituted or unsubstituted naphthalene ring or piperine ring;

[0014] R9, R 10 Each is independently selected from hydrogen, substituted or unsubstituted C1-C6 alkyl, substituted or unsubstituted C6-C12 aryl; or, R9, R 10 It forms substituted or unsubstituted C5-C6 cycloalkyl groups with the carbon atoms it is attached to;

[0015] R x For (CR) a R b )q Where q is an integer from 1 to 6, and R a R b Each is independently selected from hydrogen, substituted or unsubstituted C1~C4 alkyl groups;

[0016] The substituents are one or more of C1-C4 alkyl and C2-C4 alkenyl groups.

[0017] In some specific implementations, R1~R4 and R5~R8 are each independently selected from hydrogen, fluorine, bromine, methanesulfonyl, substituted or unsubstituted C1~C4 alkyl, substituted or unsubstituted C1~C6 alkoxy, C2~C4 carbamate, phenyl, biphenyl; or, any two adjacent R1~R4 are fused with the carbon atom of the benzene ring to which they are attached, and / or any two adjacent R5~R8 are fused with the carbon atom of the benzene ring to which they are attached, to form an unsubstituted pepper ring;

[0018] R9, R 10 Each is independently selected from hydrogen, methyl, ethyl, propyl, butyl, phenyl; or, R9, R 10 It fuses with the carbon atoms it is attached to to form cyclopentyl and cyclohexyl groups;

[0019] R x For (CR) a R b ) q Where q is an integer from 1 to 4, R a R b Each is independently selected from one or more of hydrogen, methyl, and ethyl;

[0020] The substituents are one or more of methyl, ethyl, and vinyl groups.

[0021] In some specific implementations, the multi-component copolyester includes the structures shown in formulas (1) to (17):

[0022] Equation (1); Equation (2);

[0023] Equation (3); Equation (4);

[0024] Equation (5); Equation (6); Equation (7); Equation (8); Equation (9); Equation (10); Equation (11); Equation (12); Equation (13); Equation (14); Equation (15); Equation (16); Equation (17).

[0025] In some specific implementations, the number-average molecular weight of the photochromic multi-component copolyester is 0.8 million to 70,000.

[0026] Furthermore, this application also provides a method for preparing the above-mentioned multi-component copolyester, comprising the following steps:

[0027] The catalyst, co-catalyst, and compounds of formula (III), (IV) and (V) were mixed in an inert atmosphere to carry out a polymerization reaction to obtain the photochromic multi-component copolyester of formula (I).

[0028] Equation (III) Formula (IV) Formula (V).

[0029] In some specific implementations, the catalyst is selected from triethylboron or the asymmetric Schiff base chromium shown in formula (VI);

[0030] Formula (VI);

[0031] The catalyst used is either a phosphononitrile base or a bis(triphenylphosphine)ammonium chloride.

[0032] In some specific implementations, the molar ratio of the catalyst, co-catalyst, and compounds of formula (III), (IV) and (V) is 1:(0.5~2):(50~500):(100~4000):(25~1000).

[0033] The polymerization reaction was carried out under anhydrous and oxygen-free conditions;

[0034] The polymerization reaction temperature is 60℃~100℃;

[0035] The polymerization reaction takes 6 to 360 hours.

[0036] Furthermore, this application also provides a photochromic biodegradable polyester film, which is made from the above-mentioned multi-component copolyester and polylactone.

[0037] In some specific implementations, the molar ratio of the multi-component copolyester and the polylactone is (0.5~1.5):(1.5~0.5).

[0038] The photochromic multi-component copolyester provided in this application includes a first repeating unit as shown in formula (I) and a second repeating unit as shown in formula (II); the molar ratio of the first repeating unit to the second repeating unit is (5~95):(95~5). This application introduces diarylene-based photochromic structural units and polylactone segments into the polyester molecular backbone, enabling the synthesis of block or random copolymers as needed. This synergistically endows the polyester with intrinsic photochromic properties and biodegradability, while allowing for precise control of the material's mechanical properties and degradation rate. This application also provides a photochromic biodegradable polyester film prepared from the aforementioned polyester. The film exhibits adjustable mechanical properties, rapid and stable light response, and excellent film-forming properties, achieving reversible photochromism and controllable degradation. It is suitable for fields with stringent requirements for light response performance, mechanical properties, and environmental friendliness, such as information storage and intelligent anti-counterfeiting.

[0039] Experimental results show that the film thickness of this application is adjustable, ranging from 0.02 mm to 10 mm, with tensile strength ranging from 5 MPa to 45 MPa and elongation at break ranging from 3% to 600%. The photochromic response time of the film is <5 s, and the color change can be maintained under light-protected conditions. It has certain thermal stability and can achieve cycle stability of >20 times in air. Furthermore, the degradation cycle of the prepared film in the natural environment is 120 days to 720 days. Attached Figure Description

[0040] Figure 1 This is the 1H NMR spectrum of the block copolyester prepared in Example 12;

[0041] Figure 2 This is the 1H NMR spectrum of the random copolyester prepared in Example 21;

[0042] Figure 3 The degradation curve of the film prepared in Example 12 is shown.

[0043] Figure 4 This describes the information storage and elimination process of the thin film prepared in Example 33;

[0044] Figure 5 This refers to the information storage and elimination process of the thin film prepared in Example 37. Detailed Implementation

[0045] It should be understood that the expression “one or more of…” individually includes each of the objects described after the expression, as well as various different combinations of two or more of the described objects, unless otherwise understood from the context and usage. The expression “and / or” combined with three or more described objects should be understood to have the same meaning, unless otherwise understood from the context.

[0046] The terms “including,” “having,” or “containing,” including the use of their grammatical synonyms, should generally be understood as open-ended and non-restrictive, for example, not excluding other unstated elements or steps, unless otherwise specifically stated or understood from the context.

[0047] It should be understood that the order of steps or the sequence of actions is not important as long as this application remains operational. Furthermore, two or more steps or actions can be performed simultaneously.

[0048] This application provides a photochromic multi-component copolyester, comprising a first repeating unit as shown in formula (I) and a second repeating unit as shown in formula (II):

[0049] Formula (I); Formula (II);

[0050] The molar ratio of the first repeating unit shown in formula (I) to the second repeating unit shown in formula (II) is (5~95):(95~5), preferably (20~80):(80~20), more preferably 25:75, 27:73, 40:60, 42:58, 44:56, 45:55, 47:53, 48:52, 50:50, 51:49, 52:48, 53:47, 54:46, 60:40, 61:39, 67:33 or 70:30; in some specific implementations, m=5~400, preferably m=50~350; n=20~800, preferably n=100~600;

[0051] R1~R4 and R5~R8 can be independently selected from hydrogen, halogen, substituted or unsubstituted C1~C10 alkyl sulfonyl, substituted or unsubstituted C1~C10 alkyl, substituted or unsubstituted C1~C20 alkoxy, substituted or unsubstituted C6~C20 aryl, substituted or unsubstituted C1~C20 heteroaryl, or any two adjacent R1~R4 are fused with the carbon atom of the benzene ring to which they are attached, and / or any two adjacent R5~R8 are fused with the carbon atom of the benzene ring to which they are attached, to form a substituted or unsubstituted C6~C20 fused ring.

[0052] In this application, the halogen refers to fluorine, chlorine, bromine, or iodine; the alkylsulfonyl group refers to an alkyl-SO2- group; the alkyl group refers to a straight-chain or branched aliphatic hydrocarbon group; the alkoxy group refers to an alkyl-O- group; the aryl group refers to an aromatic group containing at least one benzene ring; the heteroaryl group refers to an aromatic group containing at least one heteroatom in the aromatic ring, with the remainder being carbon atoms, wherein the heteroatom is preferably oxygen, nitrogen, or sulfur, and the heteroaryl group is a substituted or unsubstituted C4~C10 group. The heteroaryl group is more preferably 2-thienyl, 3-thienyl, 2-furanyl, 3-pyrroleyl, indolyl, benzothienyl, benzofuranyl, thiazolyl, isothiazolyl, benzothiazolyl, imidazolyl, carbazoleyl, pyrazolyl, triazolyl, pyridyl, pyrazinyl, quinolinyl, purinyl, or oxazolyl, and most preferably one of 2-thienyl, 3-thienyl, 2-furanyl, 3-pyrroleyl, thiazolyl, isothiazolyl, thiazolyl, isothiazolyl, oxazolyl, pyridyl, and pyrazinyl; the piperidine ring refers to an aromatic ring system formed by the fusion of a benzene ring and an oxygen-containing five-membered ring.

[0053] R9, R 10 Each is independently selected from hydrogen, substituted or unsubstituted C1-C10 alkyl, or substituted or unsubstituted C6-C20 aryl;

[0054] R x For (CR) a R b ) q Where q is an integer from 1 to 10, and R a R b It can be independently selected from hydrogen, substituted or unsubstituted C1 to C10 alkyl groups;

[0055] The substituents are one or more of C1-C6 alkyl groups and C2-C6 alkenyl groups.

[0056] In some specific implementations, preferably, R1~R4 and R5~R8 are each independently selected from hydrogen, fluorine, bromine, substituted or unsubstituted C1~C6 alkylsulfonyl, substituted or unsubstituted C1~C6 alkyl, substituted or unsubstituted C1~C10 alkoxy, C2~C6 carbamate, substituted or unsubstituted C6~C12 aryl, and substituted or unsubstituted C4~C10 heteroaryl; or, any two adjacent R1~R4 are fused with the carbon atom of the benzene ring to which they are attached, and / or any two adjacent R5~R8 are fused with the carbon atom of the benzene ring to which they are attached, to form a substituted or unsubstituted naphthalene ring or a piperine ring; R9, R 10 Each is independently selected from hydrogen, substituted or unsubstituted C1-C6 alkyl, substituted or unsubstituted C6-C12 aryl; or, R9, R 10 It forms a substituted or unsubstituted C5-C6 cycloalkyl group with the carbon atom it is attached to; Rx For (CR) a R b ) q Where q is an integer from 1 to 6, and R a R b Each is independently selected from hydrogen, substituted or unsubstituted C1-C4 alkyl groups; the substituted substituents are one or more of C1-C4 alkyl and C2-C4 alkenyl groups.

[0057] In some specific implementations, more preferably, R1~R4 and R5~R8 are each independently selected from hydrogen, fluorine, bromine, methanesulfonyl, substituted or unsubstituted C1~C4 alkyl, substituted or unsubstituted C1~C6 alkoxy, C2~C4 carbamate, phenyl, and biphenyl; or, any two adjacent R1~R4 are fused with the carbon atom of the benzene ring to which they are attached, and / or any two adjacent R5~R8 are fused with the carbon atom of the benzene ring to which they are attached, to form an unsubstituted naphthalene ring or a piperine ring; R9, R 10 Each is independently selected from hydrogen, methyl, ethyl, propyl, butyl, phenyl; or, R9, R 10 It fuses with the carbon atoms it is attached to to form cyclopentyl and cyclohexyl groups; R x For (CR) a R b ) q Where q is an integer from 1 to 4, R a R b Each is independently selected from one or more of hydrogen, methyl, and ethyl; the substituents are one or more of methyl, ethyl, and vinyl.

[0058] In some specific implementations, the multi-component copolyester includes the structures shown in formulas (1) to (17):

[0059] Equation (1); Equation (2);

[0060] Equation (3); Equation (4);

[0061] Equation (5); Equation (6); Equation (7); Equation (8); Equation (9); Equation (10); Equation (11); Equation (12); Equation (13); Equation (14); Equation (15); Equation (16); Equation (17).

[0062] In some specific implementations, the number average molecular weight of the photochromic multi-component copolyester is 0.8 million to 70,000; preferably 10,000 to 68,000, more preferably 10,000, 11,000, 12,000, 14,000, 15,000, 17,000, 18,000, 22,000, 25,000, 26,000, 30,000, 31,000, 35,000, 40,000, 45,000, 48,000, 59,000, or 68,000.

[0063] Furthermore, this application also provides a method for preparing the above-mentioned multi-component copolyester, comprising the following steps:

[0064] The catalyst, co-catalyst, and compounds of formula (III), (IV) and (V) were mixed in an inert atmosphere to carry out a polymerization reaction to obtain the photochromic multi-component copolyester of formula (I).

[0065] Equation (III) Formula (IV) Formula (V).

[0066] In this application, compounds of formulas (III), (IV), and (V) are used as monomers and are mixed with a catalyst and a co-catalyst in an inert atmosphere to carry out a polymerization reaction. The specific preparation process is as follows:

[0067] This application first synthesizes the acid anhydride compound shown in formula (III) according to the method described in references (Bioorg. Med. Chem. Lett. 20 (2010) 734–737 or J. Mater. Chem. C, 2017, 5, 2135--2141); in a typical synthetic process, R... a R b All are independently selected from hydrogen synthesis methods: benzoylformic acid and phenylacetic acid undergo a condensation reaction under acetic anhydride reflux conditions.

[0068] This application does not specifically limit the epoxy compound monomer in formula (IV), and any epoxy compound commonly used in the art can be used, such as one of propylene oxide, butyl oxide, hexane oxide, cyclohexane oxide, 4-vinylcyclohexane oxide, limonene oxide, and styrene oxide, preferably one of propylene oxide, butyl oxide, hexane oxide, and cyclohexane oxide; this application also does not specifically limit the source of the epoxy compound shown in formula (IV), which can be a commercially available epoxy compound or a synthetic epoxy compound, preferably a commercially available epoxy compound.

[0069] In this application, the compound of formula (V) is a cyclic lactone, preferably one of lactide, valproic acid lactone, and caprolactone; this application does not have specific restrictions on the source of the cyclic lactone, but preferably commercially available cyclic lactones.

[0070] In some specific implementations, the catalyst is selected from triethylboron or the asymmetric Schiff base chromium shown in formula (VI); block copolyesters preferably use triethylboron as the catalyst, and random copolyesters preferably use asymmetric Schiff base chromium as the catalyst.

[0071] In some specific implementations, the catalyst is selected from triethylboron or the asymmetric Schiff base chromium shown in formula (VI);

[0072] Formula (VI);

[0073] This application does not specifically limit the source of the catalyst; it can be commercially available triethylboron or a post-synthesized catalyst, with the triethylboron preferably being a commercially available product. The asymmetric Schiff base chromium is synthesized according to the method of Chinese Patent CN 114478635 B. A typical synthesis method includes the following steps:

[0074] 3,5-Di-tert-butylcatechol was reacted with 1-N-Boc-1,2-cyclohexanediamine in an organic solvent to prepare a Boc-protected intermediate. The Boc protecting group of the intermediate was removed with trifluoroacetic acid to obtain a diamine intermediate containing a free amino group. The diamine intermediate was then condensed with substituted salicylaldehyde in an alcohol solvent to prepare an asymmetric Schiff base ligand. Under an inert atmosphere, the asymmetric Schiff base ligand was coordinated with one of chromium dichloride, chromium dibromide, chromium diacetate, or chromium dinitrochloride in an organic solvent, while being exposed to air for oxidation. After post-treatment and purification, the asymmetric Schiff base chromium was obtained.

[0075] In some specific implementations, the co-catalyst is either a phosphononitrile base or bis(triphenyl)phosphonium chloride; when triethylboron is used as the catalyst, the co-catalyst is preferably a phosphononitrile base, and when an asymmetric Schiff base chromium is used as the catalyst, the co-catalyst is preferably bis(triphenyl)phosphonium chloride.

[0076] In some specific implementations, the molar ratio of the catalyst, co-catalyst, and compounds represented by formulas (III), (IV), and (V) is 1:(0.5~2):(50~500):(100~4000):(25~1000), preferably 1:(0.5~1):(300~500):(1000~4000):(400~800); the polymerization reaction is carried out under anhydrous and oxygen-free conditions; the polymerization reaction temperature is 60℃~100℃, preferably 70℃~90℃, more preferably 80℃; the polymerization reaction time is 6h~360h, preferably 30h~200h, more preferably 36h, 48h, or 120h. This application employs a one-pot method to synthesize the photochromic multi-component copolyester. In some specific implementations, the specific steps are as follows: a catalyst, a co-catalyst, a purified anhydride of formula (III), a dried epoxy compound of formula (IV), and a dried cyclic lactone of formula (V) are mixed in an inert atmosphere and subjected to a polymerization reaction. After the reaction is completed, an organic solvent is added to dissolve the mixture, and the mixture is precipitated with ethanol and dried to obtain the multi-component copolyester. In some specific implementations, the organic solvent includes dichloromethane, trichloromethane, ethyl acetate, tetrahydrofuran, acetone, toluene, and preferably dichloromethane.

[0077] Furthermore, this application also provides a photochromic biodegradable polyester film, which is made from the above-mentioned multi-component copolyester and polylactone.

[0078] In this application, the structure and source of the photochromic multi-component copolyester are as described above and will not be repeated here. The polylactone is preferably one of polycaprolactone, polylactide, and polyvalve lactone. This application does not have specific restrictions on the source of the polylactone, but commercially available polylactone products are preferred. In some specific implementations, the molar ratio of the multi-component copolyester to the polylactone is (0.5~1.5):(1.5~0.5), preferably 1:1.

[0079] In this application, the prepared film exhibits photochromic properties with a response time of <5s. The color change is maintained under light-protected conditions, and it possesses certain thermal stability, achieving a cycle stability of >20 times in air. The film thickness, tensile strength, and corresponding elongation at break can be adjusted according to actual needs. The prepared polyester film is biodegradable, with a degradation period of 120–720 days in natural environments.

[0080] This application does not impose specific limitations on the preparation method of the film. In some specific implementations, the following steps are included: dissolving the multi-component copolyester and polylactone in an organic solvent, then mixing the multi-component copolyester solution and the polylactone solution, followed by ultrasonic degassing and spin coating, and drying to obtain the film.

[0081] In some specific implementations, this application prepares the thin film according to the following steps:

[0082] The multi-component copolyester is dissolved in an organic solvent to obtain a multi-component copolyester solution, i.e., solution 1; an equimolar amount of polylactone is dissolved in an organic solvent to obtain a polylactone solution, i.e., solution 2; solutions 1 and 2 are mixed in a certain proportion and then ultrasonically degassed. The degassed solution is then dropped onto the center of the substrate surface, and a film is formed by spin coating and drying to obtain the multi-component copolyester film; in some specific implementations, the organic solvent is one of chloroform, ethyl acetate, tetrahydrofuran, and acetone, preferably chloroform; the concentration of the multi-component copolyester solution is preferably 1 kg / L; the ratio of the multi-component copolyester solution to the polylactone solution is (1~10): The ratio of the substrate is (1~10), preferably 1:(1~5), more preferably 1:1, 1:2, 1:3 or 1:4; the ultrasonic degassing time is 5min~25min, preferably 15~25min; the spin coating speed is 500~5000rpm, preferably 500~2000rpm; the spin coating time is 5s~300s, preferably 10~60s; the spin coating acceleration is 100rpm / s~200rpm / s, preferably 100~150rpm / s; this application does not have specific restrictions on the type of substrate, any substrate commonly used in the art is acceptable, such as silicon wafers, glass sheets, metal sheets, or polytetrafluoroethylene sheets.

[0083] The photochromic multi-component copolyester provided in this application includes a first repeating unit as shown in formula (I) and a second repeating unit as shown in formula (II); the molar ratio of the first repeating unit to the second repeating unit is (5~95):(95~5). This application introduces diarylene-based photochromic structural units and polylactone segments into the polyester molecular backbone, enabling the synthesis of block or random copolymers as needed. This synergistically endows the polyester with intrinsic photochromic properties and biodegradability, while allowing for precise control of the material's mechanical properties and degradation rate. This application also provides a photochromic biodegradable polyester film prepared from the aforementioned polyester. The film exhibits adjustable mechanical properties, rapid and stable light response, and excellent film-forming properties, achieving reversible photochromism and controllable degradation. It is suitable for fields with stringent requirements for light response performance, mechanical properties, and environmental friendliness, such as information storage and intelligent anti-counterfeiting.

[0084] Experimental results show that the film thickness of this application is adjustable, ranging from 0.02 mm to 10 mm, with tensile strength ranging from 5 MPa to 45 MPa and elongation at break ranging from 3% to 600%. The photochromic response time of the film is <5 s, and the color change can be maintained under light-protected conditions. It has certain thermal stability and can achieve cycle stability of >20 times in air. Furthermore, the degradation cycle of the prepared film in the natural environment is 120 days to 720 days.

[0085] The present application is further illustrated below with reference to embodiments. The scope of protection of the present application is not limited to the following embodiments.

[0086] Example 1

[0087] Under anhydrous and oxygen-free conditions, 0.01 mL of triethylboron (1 mol / L tetrahydrofuran solution), 0.01 mmol of phosphononitrile base tBu-P1, 2 mmol of cyclic anhydride, 6 mmol of caprolactone, and 4 mL of propylene oxide were mixed. The resulting mixture was stirred at 80 °C for 48 h. 3 mL of chloroform was added to the resulting reaction solution to dissolve the polymer. The polymer was then precipitated with excess ethanol, filtered, and vacuum dried for 48 h to obtain a photochromic multi-component copolyester with the structure shown in formula (1).

[0088] In this embodiment, the polyester obtained in this embodiment was characterized by proton nuclear magnetic resonance spectroscopy, wherein the ratio of alternating acid anhydride / epoxy polyester segments to polycaprolactone segments (m:n) was 25:75, and the number average molecular weight of the polyester was 48,000 by gel permeation chromatography using polystyrene as a standard.

[0089] Example 2

[0090] Under anhydrous and oxygen-free conditions, 0.01 mL of triethylboron (1 mol / L tetrahydrofuran solution), 0.01 mmol of phosphononitrile base tBu-P1, 4 mmol of cyclic anhydride, 4 mmol of caprolactone, and 4 mL of propylene oxide were mixed. The resulting mixture was stirred at 80 °C for 48 h. 3 mL of chloroform was added to the resulting reaction solution to dissolve the polymer. The polymer was then precipitated with excess ethanol, filtered, and vacuum dried for 48 h to obtain a photochromic multi-component copolyester with the structure shown in formula (1).

[0091] In this embodiment, the polyester obtained in this embodiment was characterized by proton nuclear magnetic resonance spectroscopy, wherein the ratio of alternating acid anhydride / epoxy polyester segments to polycaprolactone segments (m:n) was 53:47, and the number average molecular weight of the polyester was 31,000 by gel permeation chromatography using polystyrene as a standard.

[0092] Example 3

[0093] Under anhydrous and oxygen-free conditions, 0.01 mL of triethylboron (1 mol / L tetrahydrofuran solution), 0.01 mmol of phosphononitrile base tBu-P1, 4 mmol of cyclic anhydride, 2 mmol of caprolactone, and 3 mL of propylene oxide were mixed. The resulting mixture was stirred at 80 °C for 36 h. 3 mL of chloroform was added to the resulting reaction solution to dissolve the polymer. The polymer was then precipitated with excess ethanol, filtered, and vacuum dried for 48 h to obtain a photochromic multi-component copolyester with the structure shown in formula (1).

[0094] In this embodiment, the polyester obtained in this embodiment was characterized by proton nuclear magnetic resonance spectroscopy, wherein the ratio of acid anhydride / epoxy alternating polyester segments to polycaprolactone segments (m:n) was 70:30, and the number average molecular weight of the polyester was 40,000 by gel permeation chromatography using polystyrene as a standard.

[0095] Example 4

[0096] Under anhydrous and oxygen-free conditions, 0.01 mmol of asymmetric Schiff base chromium, 0.01 mmol of bis(triphenylphosphine) ammonium chloride, 4 mmol of cyclic anhydride, 4 mmol of caprolactone, and 4 mL of cyclohexane oxide were mixed. The resulting mixture was stirred at 80 °C for 120 h. 3 mL of chloroform was added to the resulting reaction solution to dissolve the polymer. The polymer was then precipitated with excess ethanol, filtered, and vacuum dried for 48 h to obtain a photochromic multi-component copolyester with the structure shown in formula (2).

[0097] In this embodiment, the polyester obtained in this embodiment was characterized by proton nuclear magnetic resonance spectroscopy, wherein the ratio of alternating acid anhydride / epoxy polyester segments to polylactone segments (m:n) was 51:49, and the number average molecular weight of the polyester was 30,000 by gel permeation chromatography using polystyrene as a standard.

[0098] Example 5

[0099] Under anhydrous and oxygen-free conditions, 0.01 mmol of asymmetric Schiff base chromium, 0.01 mmol of bis(triphenylphosphine) ammonium chloride, 2 mmol of cyclic anhydride, 6 mmol of caprolactone, and 4 mL of cyclohexane oxide were mixed. The resulting mixture was stirred at 80 °C for 120 h. 3 mL of chloroform was added to the resulting reaction solution to dissolve the polymer. The polymer was then precipitated with excess ethanol, filtered, and vacuum dried for 48 h to obtain a photochromic multi-component copolyester with the structure shown in formula (3).

[0100] In this embodiment, the polyester obtained in this embodiment was characterized by proton nuclear magnetic resonance spectroscopy, wherein the ratio of alternating acid anhydride / epoxy polyester segments to polylactone segments (m:n) was 27:73, and the number average molecular weight of the polyester was 35,000 by gel permeation chromatography using polystyrene as a standard.

[0101] Example 6

[0102] This embodiment uses the technical solution of Example 2 to prepare polyester. The difference is that in this embodiment, valproic acid is used instead of caprolactone in Example 2. The structure is shown in formula (3).

[0103] In this embodiment, the polyester obtained in this embodiment was characterized by proton nuclear magnetic resonance spectroscopy, wherein the ratio of alternating acid anhydride / epoxy polyester segments to polylactone segments (m:n) was 60:40, and the number average molecular weight of the polyester was 15,000 by gel permeation chromatography using polystyrene as a standard.

[0104] Example 7

[0105] This embodiment uses the technical solution of Example 2 to prepare polyester. The difference is that in this embodiment, epoxide butane is used instead of epoxide propylene oxide, and lactide is used instead of caprolactone in Example 2. The structure is shown in formula (4).

[0106] In this embodiment, the polyester obtained in this embodiment was characterized by proton nuclear magnetic resonance spectroscopy, wherein the ratio of alternating anhydride / epoxy polyester segments to polylactone segments (m:n) was 50:50, and the number average molecular weight of the polyester was 26,000 by gel permeation chromatography using polystyrene as a standard.

[0107] Example 8

[0108] This embodiment uses the technical solution of Example 2 to prepare polyester. The difference is that in this embodiment, trimethoxy-substituted acid anhydride is used instead of acid anhydride in Example 2, and epoxide butane is used instead of epoxide propylene oxide in Example 2. The structure is shown in formula (5).

[0109] In this embodiment, the polyester obtained in this embodiment was characterized by proton nuclear magnetic resonance spectroscopy, wherein the ratio of alternating acid anhydride / epoxy polyester segments to polylactone segments (m:n) was 52:48, and the number average molecular weight of the polyester was 68,000 by gel permeation chromatography using polystyrene as a standard.

[0110] Example 9

[0111] This embodiment uses the technical solution of Example 2 to prepare polyester. The difference is that in this embodiment, trimethoxy-substituted acid anhydride is used instead of acid anhydride in Example 2, epoxide is used instead of propylene oxide in Example 2, and lactide is used instead of caprolactone in Example 2. The structure is shown in formula (6).

[0112] The invention utilizes proton nuclear magnetic resonance spectroscopy to characterize the polyester obtained in this embodiment, wherein the ratio (m:n) of alternating anhydride / epoxy polyester segments to polylactone segments is 50:50, and using polystyrene as a standard, the number-average molecular weight of the polyester is 22,000 as analyzed by gel permeation chromatography.

[0113] Example 10

[0114] The present invention uses the technical solution of Example 2 to prepare polyester. The difference is that in this example, trimethoxy-substituted acid anhydride is used instead of acid anhydride in Example 2, epoxide hexane is used instead of epoxide propylene oxide in Example 2, and the ratio of acid anhydride monomer to catalyst is adjusted to 200:1. The structure is shown in formula (7).

[0115] In this embodiment, the polyester obtained was characterized using 1H NMR spectroscopy. The ratio (m:n) of the alternating anhydride / epoxy polyester segments to the polylactone segments was 45:55. Using polystyrene as a standard, the number-average molecular weight of the polyester was determined to be 14,000 by gel permeation chromatography.

[0116] Example 11

[0117] This embodiment uses the technical solution of Example 4 to prepare polyester. The difference is that in this embodiment, the anhydride is replaced by a piperon ring instead of the anhydride in Example 4, and the cyclopentane oxide is replaced by cyclohexane oxide in Example 4. The structure is shown in formula (8).

[0118] In this embodiment, polystyrene was used as a standard, and the polyester obtained in this embodiment was characterized by proton nuclear magnetic resonance spectroscopy. The ratio of alternating anhydride / epoxy polyester segments to polylactone segments (m:n) was 50:50. The number average molecular weight of the polyester was 22,000 as analyzed by gel permeation chromatography.

[0119] Example 12

[0120] This embodiment uses the technical solution of Example 2 to prepare polyester. The difference is that in this embodiment, a piperon ring is used to replace the acid anhydride in Example 2, and the structure is shown in formula (9).

[0121] Figure 1 The 1H NMR spectrum of the block copolyester prepared in Example 12 is as follows. Figure 1 As shown, the ratio of alternating anhydride / epoxy polyester segments to polylactone segments (m:n) is 67:33, and the number-average molecular weight of the polyester is 59,000, as analyzed by gel permeation chromatography using polystyrene as a standard.

[0122] Example 13

[0123] This embodiment uses the technical solution of Example 2 to prepare polyester. The difference is that this embodiment uses a double pepper ring to replace the acid anhydride in Example 2, and the ratio of acid anhydride monomer to catalyst is adjusted to 200:1. The structure is shown in formula (10).

[0124] In this embodiment, the polyester obtained in this embodiment was characterized by proton nuclear magnetic resonance spectroscopy, wherein the ratio of alternating anhydride / epoxy polyester segments to polylactone segments (m:n) was 40:60, and the number average molecular weight of the copolyester was 17,000 by gel permeation chromatography using polystyrene as a standard.

[0125] Example 14

[0126] This embodiment uses the technical solution of Example 2 to prepare polyester. The difference is that this embodiment uses 3,5-dibromosubstituted anhydride instead of the anhydride in Example 2, and the ratio of anhydride monomer to catalyst is adjusted to 200:1. The structure is shown in formula (11).

[0127] In this embodiment, the polyester obtained in this embodiment was characterized by proton nuclear magnetic resonance spectroscopy, wherein the ratio of acid anhydride / epoxy alternating polyester segments to polylactone segments (m:n) was 42:58, and the number average molecular weight of the copolyester was 11,000 by gel permeation chromatography using polystyrene as a standard.

[0128] Example 15

[0129] This embodiment uses the technical solution of Example 2 to prepare polyester. The difference is that 3,3'-dibromosubstituted anhydride is used instead of the anhydride in Example 2, and the ratio of anhydride monomer to catalyst is adjusted to 200:1. The structure is shown in formula (12).

[0130] In this embodiment, the polyester obtained in this embodiment was characterized by proton nuclear magnetic resonance spectroscopy, wherein the ratio of alternating acid anhydride / epoxy polyester segments to polylactone segments (m:n) was 48:52, and the number average molecular weight of the polyester was 10,000 by gel permeation chromatography using polystyrene as a standard.

[0131] Example 16

[0132] This embodiment uses the technical solution of Example 2 to prepare polyester. The difference is that in this embodiment, 4,4'-dibromosubstituted anhydride is used instead of the anhydride in Example 2, and the ratio of anhydride monomer to catalyst is adjusted to 200:1. The structure is shown in formula (13).

[0133] In this embodiment, the polyester obtained in this embodiment was characterized by proton nuclear magnetic resonance spectroscopy, wherein the ratio of acid anhydride / epoxy alternating polyester segments to polylactone segments (m:n) was 44:56, and the number average molecular weight of the copolyester was 12,000 by gel permeation chromatography using polystyrene as a standard.

[0134] Example 17

[0135] This embodiment uses the technical solution of Example 2 to prepare polyester. The difference is that in this embodiment, phenyl-substituted anhydride is used instead of the anhydride in Example 2, and the ratio of anhydride monomer to catalyst is adjusted to 200:1. The structure is shown in formula (14).

[0136] In this embodiment, the polyester obtained in this embodiment was characterized by proton nuclear magnetic resonance spectroscopy, wherein the ratio of acid anhydride / epoxy alternating polyester segments to polylactone segments (m:n) was 51:49, and the number average molecular weight of the copolyester was 18,000 by gel permeation chromatography using polystyrene as a standard.

[0137] Example 18

[0138] This embodiment uses the technical solution of Example 4 to prepare polyester. The difference is that this embodiment uses a naphthalene ring to replace the acid anhydride in Example 4, and the structure is shown in formula (15).

[0139] In this embodiment, the polyester obtained in this embodiment was characterized by proton nuclear magnetic resonance spectroscopy, wherein the ratio of alternating acid anhydride / epoxy polyester segments to polylactone segments (m:n) was 50:50, and the number average molecular weight of the polyester was 25,000 by gel permeation chromatography using polystyrene as a standard.

[0140] Example 19

[0141] This embodiment uses the technical solution of Example 2 to prepare polyester. The difference is that in this embodiment, hexamethoxy-substituted acid anhydride is used instead of acid anhydride in Example 2, and epoxide butane is used instead of epoxide propylene oxide in Example 2. The reaction time is adjusted to 96h, and the structure is shown in formula (16).

[0142] In this embodiment, the polyester obtained in this embodiment was characterized by proton nuclear magnetic resonance spectroscopy, wherein the ratio of alternating acid anhydride / epoxy polyester segments to polylactone segments (m:n) was 61:39, and the number average molecular weight of the polyester was 18,000 by gel permeation chromatography using polystyrene as a standard.

[0143] Example 20

[0144] This embodiment uses the technical solution of Example 4 to prepare polyester. The difference is that 4-vinylcyclohexane is used instead of cyclohexane in Example 4, and the reaction temperature is set to 100°C and the reaction time is 240h. The structure is shown in formula (17).

[0145] In this embodiment, the polyester obtained in this embodiment was characterized by proton nuclear magnetic resonance spectroscopy. This polymer is a random copolymer of anhydride / epoxy alternating polyester and polylactone with a segment ratio (m:n) of 54:46. Using polystyrene as a standard, the number average molecular weight of the polyester was analyzed by gel permeation chromatography and found to be 45,000.

[0146] Example 21

[0147] This embodiment uses the technical solution of Example 4 to prepare polyester. The difference is that propylene oxide is used instead of cyclohexane oxide in Example 4. The ratio of catalyst to co-catalyst is adjusted to 2:1. The reaction temperature is set to 100℃ and the reaction time is 360h. The structure is shown in formula (1).

[0148] The 1H NMR spectrum of the random copolyester prepared in Example 21 is as follows. Figure 2 As shown, this polymer is a random copolymer of anhydride / epoxy alternating polyester and polylactone, with a segment ratio (m:n) of 47:53. Using polystyrene as a standard, the number average molecular weight of the polyester was 26,000 by gel permeation chromatography.

[0149] Example 22

[0150] The multi-component copolyester prepared in Example 1 was dissolved in a chloroform solution with a concentration of 1 kg / L. After degassing by sonication for 15 min, 0.1 mL of the solution was dropped onto the center of a silicon wafer substrate. The solution was then spin-coated at an acceleration from 200 rpm / s to 1200 rpm for 30 s to form a film. The film was then dried in a 25°C fume hood for 48 h to obtain the multi-component copolyester film. The resulting film was yellowish-white, with a tensile strength of 8 MPa and an elongation at break of 150%. It turned red under ultraviolet light irradiation (312 nm–405 nm) with a response time < 5 s, and reverted to yellowish-white under light irradiation (≥450 nm) with a response time < 5 s.

[0151] Example 23

[0152] The multi-component copolyester prepared in Example 3 was dissolved in a chloroform solution with a concentration of 1 kg / L. After degassing by sonication for 15 min, 0.1 mL of the solution was dropped onto the center of a silicon wafer substrate. The solution was then spin-coated at an acceleration from 200 rpm / s to 1200 rpm for 30 s to form a film. The film was then dried in a fume hood at 25°C for 48 h to obtain the multi-component copolyester film. The resulting film was yellowish-white, with a tensile strength of 28 MPa and an elongation at break of 3%. It turned red under ultraviolet light irradiation (312 nm–405 nm) with a response time < 5 s, and reverted to yellowish-white under light irradiation (≥450 nm) with a response time < 5 s.

[0153] Example 24

[0154] The multi-component copolyester prepared in Example 4 was dissolved in a chloroform solution with a concentration of 1 kg / L. After degassing by sonication for 15 min, 0.1 mL of the solution was dropped onto the center of a silicon wafer substrate. The solution was then spin-coated at an acceleration from 200 rpm / s to 1200 rpm for 30 s to form a film. The film was then dried in a 25°C fume hood for 48 h to obtain the multi-component copolyester film. The resulting film was yellowish-white, with a tensile strength of 27 MPa and an elongation at break of 4%. It turned red under ultraviolet light irradiation (312 nm–405 nm) with a response time < 5 s, and reverted to yellowish-white under light irradiation (≥450 nm) with a response time < 5 s.

[0155] Example 25

[0156] The multi-component copolyester prepared in Example 5 was dissolved in a chloroform solution with a concentration of 1 kg / L. After degassing by sonication for 15 min, 0.1 mL of the solution was dropped onto the center of a silicon wafer substrate. The solution was then spin-coated at an acceleration from 200 rpm / s to 1200 rpm for 30 s to form a film. The film was then dried in a fume hood at 25°C for 48 h to obtain the multi-component copolyester film. The resulting film was yellowish-white, with a tensile strength of 10 MPa and an elongation at break of 240%. It turned red under ultraviolet light irradiation in the 312 nm–405 nm range with a response time < 5 s, and reverted to yellowish-white under light irradiation at ≥ 450 nm with a response time < 5 s.

[0157] Example 26

[0158] The multi-component copolyester prepared in Example 8 was dissolved in a chloroform solution with a concentration of 1 kg / L. After degassing by sonication for 15 min, 0.1 mL of the solution was dropped onto the center of a silicon wafer substrate. The solution was then spin-coated at an acceleration from 200 rpm / s to 1200 rpm for 30 s to form a film. The film was then dried in a fume hood at 25°C for 48 h to obtain the multi-component copolyester film. The resulting film was yellow, with a tensile strength of 40 MPa and an elongation at break of 5%. Under ultraviolet light irradiation in the 312 nm–405 nm range, it turned purplish-red with a response time < 5 s. Under irradiation with 650 nm light, it reverted to yellowish-white with a response time < 5 s.

[0159] Example 27

[0160] The multi-component copolyester prepared in Example 12 was dissolved in a chloroform solution with a concentration of 1 kg / L. After degassing by sonication for 15 min, 0.1 mL of the solution was dropped onto the center of a silicon wafer substrate. The solution was then spin-coated at an acceleration from 200 rpm / s to 1200 rpm for 30 s to form a film. The film was then dried in a 25°C fume hood for 48 h to obtain the multi-component copolyester film. The resulting film was yellow-green, with a tensile strength of 37 MPa and an elongation at break of 3%. It turned red under ultraviolet light irradiation (312 nm–405 nm) with a response time < 5 s, and reverted to yellow-green under light irradiation (450 nm–650 nm) with a response time < 5 s.

[0161] Example 28

[0162] The multi-component copolyester prepared in Example 20 was dissolved in a chloroform solution with a concentration of 1 kg / L. After degassing by sonication for 15 min, 0.1 mL of the solution was dropped onto the center of a silicon wafer substrate. The solution was then spin-coated at an acceleration from 200 rpm / s to 1200 rpm for 30 s to form a film. The film was then dried in a 25°C fume hood for 48 h to obtain the multi-component copolyester film. The resulting film was yellowish-green, with a tensile strength of 39 MPa and an elongation at break of 3%. It turned red under ultraviolet light irradiation (312 nm–405 nm) with a response time < 5 s, and reverted to yellow under light irradiation (450 nm–650 nm) with a response time < 5 s.

[0163] Example 29

[0164] The multi-component copolyester prepared in Example 21 was dissolved in a chloroform solution with a concentration of 1 kg / L. After degassing by sonication for 15 min, 0.1 mL of the solution was dropped onto the center of a silicon wafer substrate. The solution was then spin-coated at an acceleration from 200 rpm / s to 1200 rpm for 30 s to form a film. The film was then dried in a 25°C fume hood for 48 h to obtain the multi-component copolyester film. The resulting film was yellowish-white, with a tensile strength of 18 MPa and an elongation at break of 5%. It turned red under ultraviolet light irradiation (312 nm–405 nm) with a response time < 5 s, and returned to yellowish-white under light irradiation (450 nm–650 nm) with a response time < 5 s.

[0165] Example 30

[0166] The multi-component copolyester prepared in Example 2 was dissolved in chloroform solution to obtain solution 1 with a concentration of 1 kg / L. Commercially available PCL (molecular weight approximately 80 kDa) was dissolved in chloroform to obtain solution 2 with a concentration of 1 kg / L. Solution 1 and solution 2 were mixed in a 1:2 ratio and stirred thoroughly. After ultrasonication for 25 min to remove bubbles, 0.1 mL of the solution was dropped onto the center of a silicon wafer substrate. The mixture was then spin-coated at an acceleration from 200 rpm / s to 2000 rpm for 30 s to form a film. After film formation, it was placed in a fume hood at 25°C for 48 h to air dry, thus obtaining the multi-component copolyester film. The resulting film was yellowish-white, with a tensile strength of 20 MPa and an elongation at break of 500%. Under ultraviolet light irradiation of 312 nm to 405 nm, it turned red with a response time of <5 s. Under light irradiation of ≥450 nm, it returned to yellowish-white with a response time of <5 s.

[0167] Example 31

[0168] The multi-component copolyester prepared in Example 6 was dissolved in chloroform solution to obtain solution 1 with a concentration of 1 kg / L. Commercially available PCL (molecular weight approximately 80 kDa) was dissolved in chloroform to obtain solution 2 with a concentration of 1 kg / L. Solution 1 and solution 2 were mixed in a 1:3 ratio and stirred thoroughly. After ultrasonication for 25 min to remove bubbles, 0.1 mL of the solution was dropped onto the center of a silicon wafer substrate. The mixture was then spin-coated at an acceleration from 200 rpm / s to 1200 rpm for 30 s to form a film. After film formation, it was placed in a fume hood at 25°C for 48 h to air dry, thus obtaining the multi-component copolyester film. The resulting film was yellowish-white, with a tensile strength of 26 MPa and an elongation at break of 500%. Under ultraviolet light irradiation of 312 nm to 405 nm, it turned red with a response time of <5 s. Under light irradiation of ≥450 nm, it returned to yellowish-white with a response time of <5 s.

[0169] Example 32

[0170] The polyester multi-component copolyester prepared in Example 7 was dissolved in chloroform solution to obtain solution 1 with a concentration of 1 kg / L. Commercially available PLLA (molecular weight approximately 80 kDa) was dissolved in chloroform to obtain solution 2 with a concentration of 1 kg / L. Solution 1 and solution 2 were mixed in a 1:4 ratio and stirred thoroughly. After ultrasonication for 25 min to remove bubbles, 0.1 mL of the solution was dropped onto the center of a silicon wafer substrate. Spin-coating was performed at an acceleration from 200 rpm / s to 2000 rpm for 60 s to form a film. After film formation, the film was placed in a fume hood at 25°C for 48 h to air dry, thus obtaining the multi-component copolyester film. The resulting film was yellowish-white, with a tensile strength of 45 MPa and an elongation at break of 7%. Under ultraviolet light irradiation of 312 nm to 405 nm, it turned red with a response time of <5 s. Under light irradiation of ≥450 nm, it returned to yellowish-white with a response time of <5 s.

[0171] Example 33

[0172] The polyester multi-component copolyester prepared in Example 8 was dissolved in chloroform solution to obtain solution 1 with a concentration of 1 kg / L. Commercially available PCL (molecular weight approximately 80 kDa) was dissolved in chloroform to obtain solution 2 with a concentration of 1 kg / L. Solution 1 and solution 2 were mixed in a 2:3 ratio and stirred thoroughly. After ultrasonication for 25 min to remove bubbles, 0.1 mL of the solution was dropped onto the center of a silicon wafer substrate. Spin-coating was performed at an acceleration from 200 rpm / s to 2000 rpm for 30 s to form a film. After film formation, the film was placed in a fume hood at 25°C for 48 h to air dry, thus obtaining the multi-component copolyester film. The resulting film was yellow, with a tensile strength of 22 MPa and an elongation at break of 600%. Under ultraviolet light irradiation of 312 nm to 405 nm, it turned purplish-red with a response time of <5 s. Under irradiation of 650 nm light, it turned back to yellow with a response time of <5 s.

[0173] Example 34

[0174] The polyester multi-component copolyester prepared in Example 9 was dissolved in chloroform solution to obtain solution 1 with a concentration of 1 kg / L. Commercially available PLLA (molecular weight approximately 80 kDa) was dissolved in chloroform to obtain solution 2 with a concentration of 1 kg / L. Solution 1 and solution 2 were mixed in a 1:1 ratio and stirred thoroughly. After ultrasonication for 25 min to remove bubbles, 0.1 mL of the solution was dropped onto the center of a silicon wafer substrate. Spin-coating was performed at an acceleration from 200 rpm / s to 2000 rpm / s for 60 s to form a film. After film formation, the film was placed in a fume hood at 25°C for 48 h to air dry, thus obtaining the multi-component copolyester film. The resulting film was yellow, with a tensile strength of 40 MPa and an elongation at break of 8%. Under ultraviolet light irradiation of 312 nm to 405 nm, it turned purplish-red with a response time < 5 s. Under irradiation of 650 nm light, it turned back to yellow with a response time < 5 s.

[0175] Example 35

[0176] The polyester multi-component copolyester prepared in Example 10 was dissolved in chloroform solution to obtain solution 1 with a concentration of 1 kg / L. Commercially available PCL (molecular weight approximately 80 kDa) was dissolved in chloroform to obtain solution 2 with a concentration of 1 kg / L. Solution 1 and solution 2 were mixed in a 1:2 ratio and stirred thoroughly. After ultrasonication for 25 min to remove bubbles, 0.1 mL of the solution was dropped onto the center of a silicon wafer substrate. Spin-coating was performed at an acceleration from 200 rpm / s to 2000 rpm for 30 s to form a film. After film formation, the film was placed in a fume hood at 25°C for 48 h to air dry, thus obtaining the multi-component copolyester film. The resulting film was yellow, with a tensile strength of 24 MPa and an elongation at break of 600%. Under ultraviolet light irradiation of 312 nm to 405 nm, it turned purplish-red with a response time of <5 s. Under irradiation of 450 nm light, it turned back to yellow with a response time of <5 s.

[0177] Example 36

[0178] The multi-component copolyester prepared in Example 11 was dissolved in chloroform solution to obtain solution 1 with a concentration of 1 kg / L. Commercially available PCL (molecular weight approximately 80 kDa) was dissolved in chloroform to obtain solution 2 with a concentration of 1 kg / L. Solution 1 and solution 2 were mixed in a 1:3 ratio and stirred thoroughly. After ultrasonication for 25 min to remove bubbles, 0.1 mL of the solution was dropped onto the center of a silicon wafer substrate. The mixture was then spin-coated at an acceleration from 200 rpm / s to 2000 rpm for 30 s to form a film. After film formation, it was placed in a fume hood at 25°C for 48 h to air dry, thus obtaining the multi-component copolyester film. The resulting film was yellowish-white, with a tensile strength of 28 MPa and an elongation at break of 550%. It turned red under ultraviolet light irradiation in the 312 nm to 405 nm range with a response time < 5 s, and returned to yellowish-white under light irradiation ≥ 450 nm with a response time < 5 s.

[0179] Example 37

[0180] The multi-component copolyester prepared in Example 12 was dissolved in chloroform solution to obtain solution 1 with a concentration of 1 kg / L. Commercially available PCL (molecular weight approximately 80 kDa) was dissolved in chloroform to obtain solution 2 with a concentration of 1 kg / L. Solution 1 and solution 2 were mixed in a 2:3 ratio and stirred thoroughly. After ultrasonication for 25 min to remove bubbles, 0.1 mL of the solution was dropped onto the center of a silicon wafer substrate. The mixture was then spin-coated at an acceleration from 200 rpm / s to 2000 rpm for 30 s to form a film. After film formation, it was placed in a fume hood at 25°C for 48 h to air dry, thus obtaining the multi-component copolyester film. The resulting film was yellow-green, with a tensile strength of 32 MPa and an elongation at break of 640%. Under ultraviolet light irradiation of 312 nm to 405 nm, it turned red with a response time of <5 s. Under light irradiation of ≥450 nm, it reverted to yellow-green with a response time of <5 s.

[0181] Example 38

[0182] The multi-component copolyester prepared in Example 13 was dissolved in chloroform solution to obtain solution 1 with a concentration of 1 kg / L. Commercially available PCL (molecular weight approximately 80 kDa) was dissolved in chloroform to obtain solution 2 with a concentration of 1 kg / L. Solution 1 and solution 2 were mixed in a 1:4 ratio and stirred thoroughly. After ultrasonication for 25 min to remove bubbles, 0.1 mL of the solution was dropped onto the center of a silicon wafer substrate. The mixture was then spin-coated at 200 rpm for 60 s with an acceleration of 200 rpm. After film formation, the film was dried in a 25°C fume hood for 48 h to obtain the multi-component copolyester film. The resulting film was yellow, with a tensile strength of 31 MPa and an elongation at break of 600%. It turned red under ultraviolet light irradiation (312 nm–405 nm) with a response time < 5 s, and reverted to yellow under light irradiation (≥450 nm) with a response time < 5 s.

[0183] Example 39

[0184] The multi-component copolyester prepared in Example 14 was dissolved in chloroform solution to obtain solution 1 with a concentration of 1 kg / L. Commercially available PCL (molecular weight approximately 80 kDa) was dissolved in chloroform to obtain solution 2 with a concentration of 1 kg / L. Solution 1 and solution 2 were mixed in a 1:4 ratio and stirred thoroughly. After ultrasonication for 25 min to remove bubbles, 0.1 mL of the solution was dropped onto the center of a silicon wafer substrate. The mixture was then spin-coated at an acceleration from 200 rpm / s to 2000 rpm for 60 s to form a film. After film formation, it was placed in a fume hood at 25°C for 48 h to air dry, thus obtaining the multi-component copolyester film. The resulting film was light yellow, with a tensile strength of 30 MPa and an elongation at break of 600%. Under ultraviolet light irradiation of 312 nm to 405 nm, it turned light red with a response time of <5 s. Under light irradiation of ≥450 nm, it returned to light yellow with a response time of <5 s.

[0185] Example 40

[0186] The multi-component copolyester prepared in Example 15 was dissolved in chloroform solution to obtain solution 1 with a concentration of 1 kg / L. Commercially available PCL (molecular weight approximately 80 kDa) was dissolved in chloroform to obtain solution 2 with a concentration of 1 kg / L. Solution 1 and solution 2 were mixed in a 1:4 ratio and stirred thoroughly. After ultrasonication for 25 min to remove bubbles, 0.1 mL of the solution was dropped onto the center of a silicon wafer substrate. The mixture was then spin-coated at an acceleration from 200 rpm / s to 2000 rpm for 30 s to form a film. After film formation, it was placed in a fume hood at 25°C for 48 h to air dry, thus obtaining the multi-component copolyester film. The resulting film was yellow-green, with a tensile strength of 33 MPa and an elongation at break of 600%. Under ultraviolet light irradiation of 312 nm to 405 nm, it turned light red with a response time of <5 s. Under light irradiation of ≥450 nm, it returned to yellow-green with a response time of <5 s.

[0187] Example 41

[0188] The multi-component copolyester prepared in Example 16 was dissolved in chloroform to obtain solution 1 with a concentration of 1 kg / L. Commercially available PCL (molecular weight approximately 80 kDa) was dissolved in chloroform to obtain solution 2 with a concentration of 1 kg / L. Solution 1 and solution 2 were mixed in a 1:4 ratio and stirred thoroughly. After ultrasonication for 25 min to remove bubbles, 0.1 mL of the solution was dropped onto the center of a silicon wafer substrate. The mixture was then spin-coated at an acceleration from 200 rpm / s to 2000 rpm for 60 s to form a film. After film formation, it was placed in a fume hood at 25°C for 48 h to air dry, thus obtaining the multi-component copolyester film. The resulting film was yellowish-white, with a tensile strength of 32 MPa and an elongation at break of 600%. It turned red under ultraviolet light irradiation in the range of 312 nm to 405 nm with a response time < 5 s, and returned to yellowish-white under light irradiation at a concentration ≥ 450 nm with a response time < 5 s.

[0189] Example 42

[0190] The multi-component copolyester prepared in Example 17 was dissolved in chloroform to obtain solution 1 with a concentration of 1 kg / L. Commercially available PCL (molecular weight approximately 80 kDa) was dissolved in chloroform to obtain solution 2 with a concentration of 1 kg / L. Solution 1 and solution 2 were mixed in a 1:4 ratio and stirred thoroughly. After ultrasonication for 25 min to remove bubbles, 0.1 mL of the solution was dropped onto the center of a silicon wafer substrate. The mixture was then spin-coated at an acceleration from 200 rpm / s to 2000 rpm for 60 s to form a film. After film formation, it was placed in a fume hood at 25°C for 48 h to air dry, thus obtaining the multi-component copolyester film. The resulting film was yellow, with a tensile strength of 25 MPa and an elongation at break of 600%. It turned red under ultraviolet light irradiation in the 312 nm to 405 nm range with a response time < 5 s, and reverted to yellow under light irradiation at ≥ 450 nm with a response time < 5 s.

[0191] Example 43

[0192] The multi-component copolyester prepared in Example 18 was dissolved in chloroform solution to obtain solution 1 with a concentration of 1 kg / L. Commercially available PCL (molecular weight approximately 80 kDa) was dissolved in chloroform to obtain solution 2 with a concentration of 1 kg / L. Solution 1 and solution 2 were mixed in a 1:3 ratio and stirred thoroughly. After ultrasonication for 25 min to remove bubbles, 0.1 mL of the solution was dropped onto the center of a silicon wafer substrate. The mixture was then spin-coated at an acceleration from 200 rpm / s to 2000 rpm for 30 s to form a film. After film formation, it was placed in a fume hood at 25°C for 48 h to air dry, thus obtaining the multi-component copolyester film. The resulting film was yellow, with a tensile strength of 19 MPa and an elongation at break of 450%. It turned red under ultraviolet light irradiation in the 312 nm to 405 nm range with a response time < 5 s, and reverted to yellow under light irradiation at ≥ 450 nm with a response time < 5 s.

[0193] Example 44

[0194] The multi-component copolyester prepared in Example 19 was dissolved in chloroform to obtain solution 1 with a concentration of 1 kg / L. Commercially available PCL (molecular weight approximately 80 kDa) was dissolved in chloroform to obtain solution 2 with a concentration of 1 kg / L. Solution 1 and solution 2 were mixed in a 1:3 ratio and stirred thoroughly. After ultrasonication for 25 min to remove bubbles, 0.1 mL of the solution was dropped onto the center of a silicon wafer substrate. The mixture was then spin-coated at an acceleration from 200 rpm / s to 2000 rpm for 30 s to form a film. After film formation, it was placed in a fume hood at 25°C for 48 h to air dry, thus obtaining the multi-component copolyester film. The resulting film was yellow, with a tensile strength of 29 MPa and an elongation at break of 550%. It turned purple under ultraviolet light irradiation (312–405 nm) with a response time < 5 s, and reverted to yellow under light irradiation (450–650 nm) with a response time < 5 s.

[0195] Experimental Example 1

[0196] The multi-component copolyester films prepared in Examples 22-44 above can degrade in the natural environment, and the degradation period varies depending on the composition. Figure 3 This is the degradation curve of the film in Example 12, as shown below. Figure 3 As shown, the membrane containing PCL segments has a similar degradation cycle to commercial PCL, degrading within 180 to 720 days when buried in natural soil and within 90 to 360 days under composting conditions (in 1 mol / L sodium hydroxide aqueous solution); the membrane containing PLLA segments degrades within 120 to 360 days when buried in natural soil and within 30 to 180 days under composting conditions (in 1 mol / L sodium hydroxide aqueous solution).

[0197] Application Example 1

[0198] Figure 4 This is a schematic diagram of the information storage and elimination process of the thin film prepared in Example 33, as shown below. Figure 4 As shown, a corresponding magenta pattern can be written using 405nm blue-violet light via the overlay method. The pattern is then exposed to 450nm or 650nm light, which completely erases it. The pattern can then be rewritten using 365nm ultraviolet light, and can be erased using 450nm or 650nm light.

[0199] Application Example 2

[0200] Figure 5 This is a schematic diagram of the information storage and elimination process of the thin film prepared in Example 37, as shown below. Figure 5As shown, a corresponding red pattern can be written using 405nm blue-violet light via the overlay method. The written pattern can be erased under 450nm blue light, but not under 650nm red light.

[0201] The above description is merely a preferred embodiment of this application, but the scope of protection of this application is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in this application, based on the technical solution and application concept of this application, should be included within the scope of protection of this application.

Claims

1. A photochromic multi-component copolyester, characterized in that, Including the first repeating unit shown in equation (I) and the second repeating unit shown in equation (II): Formula (I); Formula (II); The molar ratio of the first repeating unit shown in formula (I) to the second repeating unit shown in formula (II) is (5~95):(95~5); R1~R4 and R5~R8 can be independently selected from hydrogen, halogen, substituted or unsubstituted C1~C10 alkyl sulfonyl, substituted or unsubstituted C1~C10 alkyl, substituted or unsubstituted C1~C20 alkoxy, substituted or unsubstituted C6~C20 aryl, substituted or unsubstituted C1~C20 heteroaryl, or any two adjacent R1~R4 are fused with the carbon atom of the benzene ring to which they are attached, and / or any two adjacent R5~R8 are fused with the carbon atom of the benzene ring to which they are attached, to form a substituted or unsubstituted C6~C20 fused ring. R9, R 10 Each is independently selected from hydrogen, substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C6-C20 aryl; or, R9, R 10 It forms substituted or unsubstituted C5-C20 polycyclic rings with the carbon atoms it is attached to; R x For (CR) a R b ) q Where q is an integer from 1 to 10, and R a R b It can be independently selected from hydrogen, substituted or unsubstituted C1 to C10 alkyl groups; The substituents are one or more of C1-C6 alkyl groups and C2-C6 alkenyl groups.

2. The photochromic multi-component copolyester according to claim 1, characterized in that, R1-R4 and R5-R8 are each independently selected from hydrogen, fluorine, bromine, substituted or unsubstituted C1-C6 alkylsulfonyl, substituted or unsubstituted C1-C6 alkyl, substituted or unsubstituted C1-C10 alkoxy, C2-C6 carbamate, substituted or unsubstituted C6-C12 aryl, substituted or unsubstituted C4-C10 heteroaryl; or, any two adjacent R1-R4 are fused with the carbon atom of the benzene ring to which they are attached, and / or any two adjacent R5-R8 are fused with the carbon atom of the benzene ring to which they are attached, to form one of the substituted or unsubstituted naphthalene ring or piperine ring; R9, R 10 Each is independently selected from hydrogen, substituted or unsubstituted C1-C6 alkyl, substituted or unsubstituted C6-C12 aryl; or, R9, R 10 It forms substituted or unsubstituted C5-C6 cycloalkyl groups with the carbon atoms it is attached to; R x For (CR) a R b ) q Where q is an integer from 1 to 6, and R a R b Each is independently selected from hydrogen, substituted or unsubstituted C1~C4 alkyl groups; The substituents are one or more of C1-C4 alkyl and C2-C4 alkenyl groups.

3. The photochromic multi-component copolyester according to claim 2, characterized in that, R1-R4 and R5-R8 are each independently selected from hydrogen, fluorine, bromine, methanesulfonyl, substituted or unsubstituted C1-C4 alkyl, substituted or unsubstituted C1-C6 alkoxy, C2-C4 carbamate, phenyl, biphenyl; or, any two adjacent R1-R4 are fused with the carbon atom of the benzene ring to which they are attached, and / or any two adjacent R5-R8 are fused with the carbon atom of the benzene ring to which they are attached, to form an unsubstituted pepper ring; R9, R 10 Each is independently selected from hydrogen, methyl, ethyl, propyl, butyl, phenyl; or, R9, R 10 It fuses with the carbon atoms it is attached to to form cyclopentyl and cyclohexyl groups; R x For (CR) a R b ) q Where q is an integer from 1 to 4, R a R b Each is independently selected from one or more of hydrogen, methyl, and ethyl; The substituents are one or more of methyl, ethyl, and vinyl groups.

4. The photochromic multi-component copolyester according to any one of claims 1 to 3, characterized in that, The multi-component copolyester includes the structures shown in formulas (1) to (17): Equation (1); Equation (2); Equation (3); Equation (4); Equation (5); Equation (6); Equation (7); Equation (8); Equation (9); Equation (10); Equation (11); Equation (12); Equation (13); Equation (14); Equation (15); Equation (16); Equation (17).

5. The copolyester according to claim 1, characterized in that, The number-average molecular weight of the photochromic multi-component copolyester is 0.8 million to 70,000.

6. A method for preparing the multi-component copolyester as described in claim 1, characterized in that, Includes the following steps: The catalyst, co-catalyst, and compounds of formula (III), (IV) and (V) were mixed in an inert atmosphere to carry out a polymerization reaction to obtain the photochromic multi-component copolyester of formula (I). Equation (III) Formula (IV) Formula (V).

7. The preparation method according to claim 6, characterized in that, The catalyst is selected from triethylboron or the asymmetric Schiff base chromium shown in formula (VI); Formula (VI); The catalyst used is either a phosphononitrile base or a bis(triphenylphosphine)ammonium chloride.

8. The preparation method according to claim 6, characterized in that, The molar ratio of the catalyst, co-catalyst, and compounds of formula (III), (IV) and (V) is 1:(0.5~2):(50~500):(100~4000):(25~1000). The polymerization reaction was carried out under anhydrous and oxygen-free conditions; The polymerization reaction temperature is 60℃~100℃; The polymerization reaction takes 6 to 360 hours.

9. A photochromic biodegradable polyester film, characterized in that, It is prepared from the multi-component copolyester and polylactone as described in any one of claims 1 to 5.

10. The thin film according to claim 9, characterized in that, The molar ratio of the multi-component copolyester and polylactone is (0.5~1.5):(1.5~0.5).

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