Photochromic spandex fiber based on sulfydryl-alkene click reaction and preparation method
The spiroxazine compound was grafted into polyurethane fibers through thiol-ene click reaction, and the photochromic spandex fiber was prepared by electrospinning method, which solved the difficulty of introducing photochromic compounds in the prior art and realized the unique light of spandex fibers Discoloration effect and chemical stability.
Patent Information
- Application Number
- CN202411789455.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-06
- Publication Date
- 2025-02-14
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
The prior art is difficult to introduce photochromic compounds into spandex fibers through chemical grafting reactions through simple and efficient synthesis methods to achieve the photochromic effect of clothing and apparel.
The thiol-ene click reaction was used to introduce the spirooxazine compound into the polyurethane fibers through chemical grafting reaction, and the phototripleted spandex fibers were prepared by electrospinning.
The photochromic effect of spandex fiber is achieved, and the spiroazine compound is evenly dispersed in the fiber matrix, the chemical bonds are firmly bonded, and have photochemical stability and fatigue resistance.
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Figure CN119433747A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of spandex fibers, in particular to a photochromic spandex fiber based on a mercapto-ene click reaction and a preparation method thereof. Background Art
[0002] Polyurethane fiber, the main component of spandex, is an elastic fiber with the advantages of high elongation at break, low modulus and high elastic recovery rate. Spandex fiber can be used in clothing and accessories that require high stretchability and comfort, such as professional sportswear, fitness wear, basketball uniforms, tights, rowing suits, underwear, performance costumes and other clothing.
[0003] In order to expand the practical application of spandex materials, functional modification of polyurethane fibers to give them new functions is a hot research topic. In recent years, color-changing materials have been added to clothing and accessories to give them unique color-changing effects, which meets the consumers' pursuit of novel, unique and avant-garde trends in clothing and accessories, and is becoming more and more popular with the public. The polyurethane fibers grafted with photochromic compounds can be made into photochromic clothing and accessories, which has broad application prospects. Common photochromic compounds mainly include spirooxazine compounds, spiropyran compounds, phenoxynaphthoquinones, etc., but how to introduce these photochromic compounds into spandex fibers through chemical grafting reactions through simple and efficient synthesis methods has become a research difficulty. Summary of the invention
[0004] In view of the deficiencies in the prior art, the present invention provides a photochromic spandex fiber based on a mercapto-ene click reaction and a preparation method thereof, so that the spandex fiber has a unique photochromic effect.
[0005] To achieve the above object, the present invention provides the following technical solution: a photochromic spandex fiber based on thiol-ene click reaction, wherein the preparation method of the photochromic spandex fiber based on thiol-ene click reaction comprises the following steps: (1) Add deionized water, 2,7-dihydroxynaphthalene and sodium hydroxide to a flask, stir to dissolve, place in an ice water bath, add sodium nitrite, stir to react for 1-2 h, slowly add concentrated sulfuric acid dropwise, react for 3-4 h, filter the solvent, wash the product with deionized water until neutral, and obtain 1-nitroso-2,7-dihydroxynaphthalene with the molecular formula C 10 H4NO3.
[0006] (2) Add ethanol solvent, 1-(8-bromooctyl)-3,3-dimethyl-2-methyleneindoline and 1-nitroso-2,7-dihydroxynaphthalene to a flask, stir and dissolve, then add in nitrogen atmosphere to carry out cyclization reaction, remove the solvent by vacuum distillation, and wash the product with ether to obtain a bromospirooxazine compound with the molecular formula C 29 H33 NO2Br.
[0007] (3) nitrogen is introduced into the flask, and an ethanol solvent, a bromospirooxazine compound and potassium thioacetate are added to carry out a nucleophilic substitution reaction, and the solvent is removed by distillation under reduced pressure. The mixed product is extracted by adding dichloromethane solvent and dilute hydrochloric acid. The dichloromethane organic phase is taken and distilled under reduced pressure, and the crude product is placed in an ethanol solvent for recrystallization to obtain a mercaptospirooxazine compound with a molecular formula of C 29 H 34 N2O2S.
[0008] (4) Nitrogen is introduced into the flask, 4,4'-diphenylmethane diisocyanate and polytetramethylene glycol are added, and the reaction is carried out at 80-90 °C for 1-3 h. The temperature is then reduced to 60-70 °C, and 1,4-butanediol is added and the reaction is carried out for 1-2 h. Acetone is added to adjust the viscosity of the solution, and a capping agent, hydroxyethyl methacrylate, is added and the reaction is carried out for 2-3 h. Triethylamine is added for neutralization, and deionized water is added. After high-speed emulsification, a terminal olefin polyurethane emulsion is obtained.
[0009] (5) Adding a mercapto spirooxazine compound to the olefin-terminated polyurethane emulsion to carry out a mercapto-ene click reaction, distilling the solution under reduced pressure to remove the solvent, and washing the product with deionized water and ethanol to obtain a spirooxazine compound-grafted polyurethane.
[0010] (6) The spirooxazine compound grafted polyurethane is placed in an N,N-dimethylacetamide solvent and stirred evenly to form a spinning solution. The photochromic spandex fiber based on the thiol-ene click reaction is obtained by electrospinning.
[0011] Preferably, in the step (2), the mass ratio of 1-(8-bromooctyl)-3,3-dimethyl-2-methyleneindoline to 1-nitroso-2,7-dihydroxynaphthalene is 100:110-130.
[0012] Preferably, the temperature of the cyclization reaction in step (2) is 20-40°C, and the reaction time is 6-12 h.
[0013] Preferably, the mass ratio of the bromospirooxazine compound to potassium thioacetate in step (2) is 100:55-80.
[0014] Preferably, the temperature of the nucleophilic substitution reaction in step (3) is 50-70° C., and the reaction time is 6-12 h.
[0015] Preferably, in the step (4), the mass ratio of 4,4'-diphenylmethane diisocyanate, polytetramethylene ether glycol, 1,4-butanediol and hydroxyethyl methacrylate is 40-60:100:3-6:2-4.
[0016] Preferably, in the step (5), the mass ratio of the solid content of the terminal olefin polyurethane emulsion to the mercapto spirooxazine compound is 100:5-25.
[0017] Preferably, the thiol-ene click reaction in step (5) is carried out under ultraviolet light for 4-10 h at a reaction temperature of 50-70°C.
[0018] Compared with the prior art, the present invention has the following beneficial technical effects: The photochromic spandex fiber based on the mercapto-ene click reaction is prepared by a cyclization reaction between 1-(8-bromooctyl)-3,3-dimethyl-2-methyleneindoline and 1-nitroso-2,7-dihydroxynaphthalene to obtain a bromospirooxazine compound containing a bromine atom in the side chain, and the bromine atom undergoes a nucleophilic substitution reaction with potassium thioacetate to generate a mercapto group, thereby obtaining a mercaptospirooxazine compound.
[0019] The photochromic spandex fiber based on mercapto-ene click reaction is prepared by first polymerizing 4,4'-diphenylmethane diisocyanate and polytetramethylene ether diol to generate terminal isocyanate polyurethane, and then using hydroxyethyl methacrylate as a capping agent to obtain terminal olefin polyurethane emulsion, thereby introducing olefin functional groups at the chain ends of the polyurethane.
[0020] The photochromic spandex fiber based on thiol-ene click reaction is based on a simple and efficient thiol-ene click reaction, so that the olefinic group at the end of the polyurethane chain and the thiol group of the thiol spirooxazine compound undergo a rapid click reaction, thereby grafting the spirooxazine compound into the molecular chain of the polyurethane through chemical bond connection to obtain the spirooxazine compound grafted polyurethane, and further obtaining the spandex fiber through electrostatic spinning. The spirooxazine compound is uniformly dispersed in the spandex fiber matrix, and the chemical bond is also very strong. Under ultraviolet light irradiation, the carbon-oxygen single bond in the molecular structure of the spirooxazine compound absorbs energy, the bond breaks, causing the electronic valence state to be rearranged, the molecule to open the ring, and a conjugated system is formed. The molecular structure is closed again under light protection, so that different light absorbance is obtained and different color changes are presented. In addition, the spirooxazine compound has the advantages of photochemical stability and fatigue resistance, so that the spandex fiber has a unique photochromic effect. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 It is the reaction formula of 1-(8-bromooctyl)-3,3-dimethyl-2-methyleneindoline and 1-nitroso-2,7-dihydroxynaphthalene; Figure 2 It is the reaction formula of bromospirooxazine compound and potassium thioacetate. DETAILED DESCRIPTION
[0022] To achieve the above object, the present invention provides the following specific implementation methods and examples: A method for preparing photochromic spandex fiber based on mercapto-ene click reaction comprises the following steps: (1) Add deionized water, 2,7-dihydroxynaphthalene and sodium hydroxide to a flask, stir to dissolve, place in an ice water bath, add sodium nitrite, stir to react for 1-2 h, slowly add concentrated sulfuric acid dropwise, react for 3-4 h, filter the solvent, wash the product with deionized water until neutral, and obtain 1-nitroso-2,7-dihydroxynaphthalene with the molecular formula C 10 H4NO3.
[0023] (2) Add ethanol solvent, 1-(8-bromooctyl)-3,3-dimethyl-2-methyleneindoline and 1-nitroso-2,7-dihydroxynaphthalene in a mass ratio of 100:110-130 to a flask, stir and dissolve, then add in a nitrogen atmosphere to carry out a cyclization reaction at a reaction temperature of 20-40 °C for a reaction time of 6-12 h. Remove the solvent by distillation under reduced pressure, and wash the product with ether to obtain a bromospirooxazine compound with a molecular formula of C 29 H 33 NO2Br.
[0024] (3) nitrogen is introduced into the flask, and an ethanol solvent, a bromospirooxazine compound and potassium thioacetate in a mass ratio of 100:55-80 are added to carry out a nucleophilic substitution reaction. The reaction temperature is 50-70°C and the reaction time is 6-12 h. The solvent is removed by distillation under reduced pressure. The mixed product is extracted by adding dichloromethane solvent and dilute hydrochloric acid. The dichloromethane organic phase is taken and distilled under reduced pressure. The crude product is placed in an ethanol solvent for recrystallization to obtain a mercaptospirooxazine compound with a molecular formula of C 29 H 34 N2O2S.
[0025] (4) Nitrogen is introduced into the flask, 4,4'-diphenylmethane diisocyanate and polytetramethylene glycol are added, and the reaction is carried out at 80-90°C for 1-3 h. The temperature is then reduced to 60-70°C, and 1,4-butanediol is added and the reaction is carried out for 1-2 h. Acetone is added to adjust the viscosity of the solution, and then a capping agent, hydroxyethyl methacrylate, is added, wherein the mass ratio of 4,4'-diphenylmethane diisocyanate, polytetramethylene glycol, 1,4-butanediol and hydroxyethyl methacrylate is 40-60:100:3-6:2-4. The reaction is carried out for 2-3 h, and triethylamine is added for neutralization. Deionized water is added, and after high-speed emulsification, a terminal olefin polyurethane emulsion is obtained.
[0026] (5) Adding a mercapto spirooxazine compound to a terminal olefin polyurethane emulsion, controlling the mass ratio of the solid content in the emulsion to the mercapto spirooxazine compound to be 100:5-25, carrying out a mercapto-ene click reaction under ultraviolet light for 4-10 h at a reaction temperature of 50-70 °C, distilling the solution under reduced pressure to remove the solvent, and washing the product with deionized water and ethanol to obtain a spirooxazine compound grafted polyurethane.
[0027] (6) The spirooxazine compound grafted polyurethane is placed in an N,N-dimethylacetamide solvent and stirred evenly to form a spinning solution. The photochromic spandex fiber based on the thiol-ene click reaction is obtained by electrospinning. Example 1
[0028] (1) Add deionized water, 2,7-dihydroxynaphthalene and sodium hydroxide to a flask, stir to dissolve, place in an ice water bath, add sodium nitrite, stir to react for 1 h, slowly add concentrated sulfuric acid dropwise, react for 3 h, filter the solvent, wash the product with deionized water until neutral, and obtain 1-nitroso-2,7-dihydroxynaphthalene with the molecular formula C 10 H4NO3.
[0029] (2) Add ethanol solvent, 1-(8-bromooctyl)-3,3-dimethyl-2-methyleneindoline and 1-nitroso-2,7-dihydroxynaphthalene in a mass ratio of 100:110 into a flask, stir and dissolve, then add in a nitrogen atmosphere to carry out a cyclization reaction at a reaction temperature of 20 °C for 6 h. Remove the solvent by distillation under reduced pressure, and wash the product with ether to obtain a bromospirooxazine compound with a molecular formula of C 29 H 33 NO2Br.
[0030] (3) Nitrogen was introduced into the flask, and an ethanol solvent, a bromospirooxazine compound and potassium thioacetate in a mass ratio of 100:55 were added to carry out a nucleophilic substitution reaction. The reaction temperature was 50 °C and the reaction time was 6 h. The solvent was removed by distillation under reduced pressure. The mixed product was extracted by adding dichloromethane solvent and dilute hydrochloric acid. The dichloromethane organic phase was taken and distilled under reduced pressure. The crude product was placed in an ethanol solvent for recrystallization to obtain a mercaptospirooxazine compound with a molecular formula of C 29 H 34 N2O2S.
[0031] (4) Nitrogen was introduced into the flask, and 4,4'-diphenylmethane diisocyanate and polytetramethylene glycol were added. The reaction was carried out at 80°C for 1 h. The temperature was then reduced to 60°C, and 1,4-butanediol was added. The reaction was carried out for 1 h. Acetone was added to adjust the viscosity of the solution. The end-capping agent hydroxyethyl methacrylate was added, wherein the mass ratio of 4,4'-diphenylmethane diisocyanate, polytetramethylene glycol, 1,4-butanediol and hydroxyethyl methacrylate was 40:100:3:2. The reaction was carried out for 2 h. Triethylamine was added for neutralization, and deionized water was added. After high-speed emulsification, a terminal olefin polyurethane emulsion was obtained.
[0032] (5) Adding a mercapto spirooxazine compound to a terminal olefin polyurethane emulsion, controlling the mass ratio of the solid content in the emulsion to the mercapto spirooxazine compound to be 100:5, carrying out a mercapto-ene click reaction under ultraviolet light for 4 h at a reaction temperature of 50 °C, distilling the solution under reduced pressure to remove the solvent, and washing the product with deionized water and ethanol to obtain a spirooxazine compound-grafted polyurethane.
[0033] (6) The spirooxazine compound grafted polyurethane is placed in an N,N-dimethylacetamide solvent and stirred evenly to form a spinning solution. The photochromic spandex fiber based on the thiol-ene click reaction is obtained by electrospinning. Example 2
[0034] (1) Add deionized water, 2,7-dihydroxynaphthalene and sodium hydroxide to a flask, stir to dissolve, place in an ice water bath, add sodium nitrite, stir to react for 2 h, slowly add concentrated sulfuric acid dropwise, react for 3 h, filter the solvent, wash the product with deionized water until neutral, and obtain 1-nitroso-2,7-dihydroxynaphthalene with the molecular formula C 10 H4NO3.
[0035] (2) Add ethanol solvent, 1-(8-bromooctyl)-3,3-dimethyl-2-methyleneindoline and 1-nitroso-2,7-dihydroxynaphthalene in a mass ratio of 100:105 into a flask, stir and dissolve, then add in a nitrogen atmosphere to carry out a cyclization reaction at a reaction temperature of 40 °C and a reaction time of 12 h. Remove the solvent by distillation under reduced pressure, and wash the product with ether to obtain a bromospirooxazine compound with a molecular formula of C 29 H 33 NO2Br.
[0036] (3) Nitrogen was introduced into the flask, and an ethanol solvent, a bromospirooxazine compound and potassium thioacetate in a mass ratio of 100:65 were added to carry out a nucleophilic substitution reaction. The reaction temperature was 70 °C and the reaction time was 8 h. The solvent was removed by distillation under reduced pressure. The mixed product was extracted with dichloromethane solvent and dilute hydrochloric acid. The dichloromethane organic phase was taken and distilled under reduced pressure. The crude product was placed in an ethanol solvent for recrystallization to obtain a mercaptospirooxazine compound with a molecular formula of C 29 H 34 N2O2S.
[0037] (4) Nitrogen was introduced into the flask, and 4,4'-diphenylmethane diisocyanate and polytetramethylene glycol were added. The reaction was carried out at 80 °C for 2 h. The temperature was then reduced to 65 °C, and 1,4-butanediol was added. The reaction was carried out for 2 h. Acetone was added to adjust the viscosity of the solution, and then hydroxyethyl methacrylate as a capping agent was added. The mass ratio of 4,4'-diphenylmethane diisocyanate, polytetramethylene glycol, 1,4-butanediol and hydroxyethyl methacrylate was 45:100:4:2.5. The reaction was carried out for 2.5 h. Triethylamine was added for neutralization, and deionized water was added. After high-speed emulsification, a terminal olefin polyurethane emulsion was obtained.
[0038] (5) Adding a mercapto spirooxazine compound to a terminal olefin polyurethane emulsion, controlling the mass ratio of the solid content in the emulsion to the mercapto spirooxazine compound to be 100:10, carrying out a mercapto-ene click reaction under ultraviolet light for 6 h at a reaction temperature of 70 °C, distilling the solution under reduced pressure to remove the solvent, and washing the product with deionized water and ethanol to obtain a spirooxazine compound-grafted polyurethane.
[0039] (6) The spirooxazine compound grafted polyurethane is placed in an N,N-dimethylacetamide solvent and stirred evenly to form a spinning solution. The photochromic spandex fiber based on the thiol-ene click reaction is obtained by electrospinning. Example 3
[0040] (1) Add deionized water, 2,7-dihydroxynaphthalene and sodium hydroxide to a flask, stir to dissolve, place in an ice water bath, add sodium nitrite, stir to react for 1.5 h, slowly add concentrated sulfuric acid dropwise, react for 3.5 h, filter the solvent, and wash the product with deionized water until it is neutral to obtain 1-nitroso-2,7-dihydroxynaphthalene, with the molecular formula C 10 H4NO3.
[0041] (2) Add ethanol solvent, 1-(8-bromooctyl)-3,3-dimethyl-2-methyleneindoline and 1-nitroso-2,7-dihydroxynaphthalene in a mass ratio of 100:122 to a flask, stir and dissolve, then add in a nitrogen atmosphere to carry out a cyclization reaction at a reaction temperature of 30 °C for 8 h. Distill under reduced pressure to remove the solvent, and wash the product with ether to obtain a bromospirooxazine compound with a molecular formula of C 29 H 33 NO2Br.
[0042] (3) Nitrogen was introduced into the flask, and an ethanol solvent, a bromospirooxazine compound and potassium thioacetate in a mass ratio of 100:72 were added to carry out a nucleophilic substitution reaction. The reaction temperature was 60 °C and the reaction time was 8 h. The solvent was removed by distillation under reduced pressure. The mixed product was extracted with dichloromethane solvent and dilute hydrochloric acid. The dichloromethane organic phase was taken and distilled under reduced pressure. The crude product was placed in an ethanol solvent for recrystallization to obtain a mercaptospirooxazine compound with a molecular formula of C 29 H 34 N2O2S.
[0043] (4) Nitrogen was introduced into the flask, and 4,4'-diphenylmethane diisocyanate and polytetramethylene glycol were added. The reaction was carried out at 85 °C for 2 h. The temperature was then reduced to 65 °C, and 1,4-butanediol was added. The reaction was carried out for 1.5 h. Acetone was added to adjust the viscosity of the solution. The end-capping agent hydroxyethyl methacrylate was added. The mass ratio of 4,4'-diphenylmethane diisocyanate, polytetramethylene glycol, 1,4-butanediol and hydroxyethyl methacrylate was 52:100:5:3.5. The reaction was carried out for 2.5 h. Triethylamine was added for neutralization. Deionized water was added, and a terminal olefin polyurethane emulsion was obtained after high-speed emulsification.
[0044] (5) Adding a mercapto spirooxazine compound to a terminal olefin polyurethane emulsion, controlling the mass ratio of the solid content in the emulsion to the mercapto spirooxazine compound to be 100:20, carrying out a mercapto-ene click reaction under ultraviolet light for 6 h at a reaction temperature of 60 °C, distilling the solution under reduced pressure to remove the solvent, and washing the product with deionized water and ethanol to obtain a spirooxazine compound-grafted polyurethane.
[0045] (6) The spirooxazine compound grafted polyurethane is placed in an N,N-dimethylacetamide solvent and stirred evenly to form a spinning solution. The photochromic spandex fiber based on the thiol-ene click reaction is obtained by electrospinning. Example 4
[0046] (1) Add deionized water, 2,7-dihydroxynaphthalene and sodium hydroxide to a flask, stir to dissolve, place in an ice water bath, add sodium nitrite, stir to react for 2 h, slowly add concentrated sulfuric acid dropwise, react for 4 h, filter the solvent, wash the product with deionized water until neutral, and obtain 1-nitroso-2,7-dihydroxynaphthalene with the molecular formula C 10 H4NO3.
[0047] (2) Add ethanol solvent, 1-(8-bromooctyl)-3,3-dimethyl-2-methyleneindoline and 1-nitroso-2,7-dihydroxynaphthalene in a mass ratio of 100:130 into a flask, stir and dissolve, then add in a nitrogen atmosphere to carry out a cyclization reaction at a reaction temperature of 40 °C and a reaction time of 12 h. Remove the solvent by distillation under reduced pressure, and wash the product with ether to obtain a bromospirooxazine compound with a molecular formula of C 29 H 33 NO2Br.
[0048] (3) Nitrogen was introduced into the flask, and an ethanol solvent, a bromospirooxazine compound and potassium thioacetate in a mass ratio of 100:80 were added to carry out a nucleophilic substitution reaction. The reaction temperature was 70 °C and the reaction time was 12 h. The solvent was removed by distillation under reduced pressure. The mixed product was extracted with dichloromethane solvent and dilute hydrochloric acid. The dichloromethane organic phase was taken and distilled under reduced pressure. The crude product was placed in an ethanol solvent for recrystallization to obtain a mercaptospirooxazine compound with a molecular formula of C 29 H 34 N2O2S.
[0049] (4) Nitrogen was introduced into the flask, and 4,4'-diphenylmethane diisocyanate and polytetramethylene glycol were added. The reaction was carried out at 90 °C for 3 h. The temperature was then lowered to 70 °C, and 1,4-butanediol was added. The reaction was carried out for 2 h. Acetone was added to adjust the viscosity of the solution. The end-capping agent hydroxyethyl methacrylate was added, wherein the mass ratio of 4,4'-diphenylmethane diisocyanate, polytetramethylene glycol, 1,4-butanediol and hydroxyethyl methacrylate was 60:100:6:4. The reaction was carried out for 3 h. Triethylamine was added for neutralization, and deionized water was added. After high-speed emulsification, a terminal olefin polyurethane emulsion was obtained.
[0050] (5) Adding a mercapto spirooxazine compound to a terminal olefin polyurethane emulsion, controlling the mass ratio of the solid content in the emulsion to the mercapto spirooxazine compound to be 100:25, carrying out a mercapto-ene click reaction under ultraviolet light for 10 h at a reaction temperature of 70 °C, distilling the solution under reduced pressure to remove the solvent, and washing the product with deionized water and ethanol to obtain a spirooxazine compound grafted polyurethane.
[0051] (6) The spirooxazine compound grafted polyurethane is placed in an N,N-dimethylacetamide solvent and stirred evenly to form a spinning solution. The photochromic spandex fiber based on the thiol-ene click reaction is obtained by electrospinning.
[0052] Comparative Example 1 (1) Add deionized water, 2,7-dihydroxynaphthalene and sodium hydroxide to a flask, stir to dissolve, place in an ice water bath, add sodium nitrite, stir to react for 2 h, slowly add concentrated sulfuric acid dropwise, react for 3 h, filter the solvent, wash the product with deionized water until neutral, and obtain 1-nitroso-2,7-dihydroxynaphthalene with the molecular formula C 10 H4NO3.
[0053] (2) Add ethanol solvent, 1-(8-bromooctyl)-3,3-dimethyl-2-methyleneindoline and 1-nitroso-2,7-dihydroxynaphthalene in a mass ratio of 100:102 to a flask, stir and dissolve, then add in a nitrogen atmosphere to carry out a cyclization reaction at a reaction temperature of 20 °C and a reaction time of 8 h. Remove the solvent by distillation under reduced pressure, and wash the product with ether to obtain a bromospirooxazine compound with a molecular formula of C 29 H 33 NO2Br.
[0054] (3) Nitrogen was introduced into the flask, and an ethanol solvent, a bromospirooxazine compound and potassium thioacetate in a mass ratio of 100:45 were added to carry out a nucleophilic substitution reaction. The reaction temperature was 70 °C and the reaction time was 12 h. The solvent was removed by distillation under reduced pressure. The mixed product was extracted with dichloromethane solvent and dilute hydrochloric acid. The dichloromethane organic phase was taken and distilled under reduced pressure. The crude product was placed in an ethanol solvent for recrystallization to obtain a mercaptospirooxazine compound with a molecular formula of C 29 H 34 N2O2S.
[0055] (4) Nitrogen was introduced into the flask, and 4,4'-diphenylmethane diisocyanate and polytetramethylene glycol were added. The reaction was carried out at 90 °C for 1 h. The temperature was then reduced to 65 °C, and 1,4-butanediol was added. The reaction was carried out for 1 h. Acetone was added to adjust the viscosity of the solution. The end-capping agent hydroxyethyl methacrylate was added. The mass ratio of 4,4'-diphenylmethane diisocyanate, polytetramethylene glycol, 1,4-butanediol and hydroxyethyl methacrylate was 32:100:2:1.5. The reaction was carried out for 2.5 h. Triethylamine was added for neutralization. Deionized water was added, and a terminal olefin polyurethane emulsion was obtained after high-speed emulsification.
[0056] (5) Adding a mercapto spirooxazine compound to a terminal olefin-based polyurethane emulsion, controlling the mass ratio of the solid content in the emulsion to the mercapto spirooxazine compound to be 100:2, carrying out a mercapto-ene click reaction under ultraviolet light for 8 h at a reaction temperature of 60 °C, distilling the solution under reduced pressure to remove the solvent, and washing the product with deionized water and ethanol to obtain a spirooxazine compound-grafted polyurethane.
[0057] (6) The spirooxazine compound grafted polyurethane is placed in an N,N-dimethylacetamide solvent and stirred evenly to form a spinning solution. The photochromic spandex fiber based on the thiol-ene click reaction is obtained by electrospinning.
[0058] Comparative Example 2 (1) Add deionized water, 2,7-dihydroxynaphthalene and sodium hydroxide to a flask, stir to dissolve, place in an ice water bath, add sodium nitrite, stir to react for 2 h, slowly add concentrated sulfuric acid dropwise, react for 4 h, filter the solvent, wash the product with deionized water until neutral, and obtain 1-nitroso-2,7-dihydroxynaphthalene with the molecular formula C 10 H4NO3.
[0059] (2) Add ethanol solvent, 1-(8-bromooctyl)-3,3-dimethyl-2-methyleneindoline and 1-nitroso-2,7-dihydroxynaphthalene in a mass ratio of 100:138 to a flask, stir to dissolve, and then add in a nitrogen atmosphere to carry out a cyclization reaction at a reaction temperature of 30 °C for 6 h. Remove the solvent by distillation under reduced pressure, and wash the product with ether to obtain a bromospirooxazine compound with a molecular formula of C 29 H 33 NO2Br.
[0060] (3) Nitrogen was introduced into the flask, and an ethanol solvent, a bromospirooxazine compound and potassium thioacetate in a mass ratio of 100:90 were added to carry out a nucleophilic substitution reaction. The reaction temperature was 70 °C and the reaction time was 6 h. The solvent was removed by distillation under reduced pressure. The mixed product was extracted with dichloromethane solvent and dilute hydrochloric acid. The dichloromethane organic phase was taken and distilled under reduced pressure. The crude product was placed in an ethanol solvent for recrystallization to obtain a mercaptospirooxazine compound with a molecular formula of C 29 H 34 N2O2S.
[0061] (4) Nitrogen was introduced into the flask, and 4,4'-diphenylmethane diisocyanate and polytetramethylene glycol were added. The reaction was carried out at 85 °C for 3 h. The temperature was then reduced to 65 °C, and 1,4-butanediol was added. The reaction was carried out for 2 h. Acetone was added to adjust the viscosity of the solution. The end-capping agent hydroxyethyl methacrylate was added, wherein the mass ratio of 4,4'-diphenylmethane diisocyanate, polytetramethylene glycol, 1,4-butanediol and hydroxyethyl methacrylate was 68:100:7:4.5. The reaction was carried out for 2.5 h. Triethylamine was added for neutralization, and deionized water was added. After high-speed emulsification, a terminal olefin polyurethane emulsion was obtained.
[0062] (5) Adding a mercapto spirooxazine compound to the terminal olefin polyurethane emulsion, controlling the mass ratio of the solid content in the emulsion to the mercapto spirooxazine compound to be 100:32, carrying out a mercapto-ene click reaction under ultraviolet light for 8 h at a reaction temperature of 60 °C, distilling the solution under reduced pressure to remove the solvent, and washing the product with deionized water and ethanol to obtain a spirooxazine compound-grafted polyurethane.
[0063] (6) The spirooxazine compound grafted polyurethane is placed in an N,N-dimethylacetamide solvent and stirred evenly to form a spinning solution. The photochromic spandex fiber based on the thiol-ene click reaction is obtained by electrospinning.
[0064] The absorption coefficient K and scattering coefficient S of the photochromic spandex fiber based on the thiol-ene click reaction were tested using a CS-820N colorimeter, and the K / S value was calculated. The fiber was then irradiated under a 20 W UV lamp for 10 min, and its absorption coefficient K and scattering coefficient S were tested, and the K / S value was calculated.
[0065]
Claims
1. A photochromic spandex fiber based on mercapto-ene click reaction, characterized in that: The preparation method of the photochromic spandex fiber based on the mercapto-ene click reaction comprises the following steps: (1) Add deionized water, 2,7-dihydroxynaphthalene and sodium hydroxide to a flask, stir to dissolve, place in an ice water bath, add sodium nitrite, stir to react for 1-2 h, slowly add concentrated sulfuric acid dropwise, react for 3-4 h, and obtain 1-nitroso-2,7-dihydroxynaphthalene, with the molecular formula C 10 H4NO3; (2) Add ethanol solvent, 1-(8-bromooctyl)-3,3-dimethyl-2-methyleneindoline and 1-nitroso-2,7-dihydroxynaphthalene to the flask, stir and dissolve, then add in nitrogen atmosphere to carry out cyclization reaction to obtain a bromospirooxazine compound with the molecular formula C 29 H 33 NO2Br; (3) Nitrogen is introduced into the flask, and ethanol solvent, bromospirooxazine compound and potassium thioacetate are added to carry out a nucleophilic substitution reaction to obtain a mercaptospirooxazine compound with the molecular formula C 29 H 34 N2O2S; (4) nitrogen is introduced into the flask, 4,4'-diphenylmethane diisocyanate and polytetramethylene glycol are added, the reaction is carried out at 80-90°C for 1-3 h, the temperature is lowered to 60-70°C, 1,4-butanediol is added, the reaction is carried out for 1-2 h, acetone is added to adjust the viscosity of the solution, and hydroxyethyl methacrylate as a blocking agent is added, the reaction is carried out for 2-3 h, triethylamine is added for neutralization, deionized water is added, and after high-speed emulsification, a terminal olefin polyurethane emulsion is obtained; (5) adding a mercapto spirooxazine compound to the olefin-terminated polyurethane emulsion to carry out a mercapto-ene click reaction to obtain a spirooxazine compound-grafted polyurethane; (6) The spirooxazine compound grafted polyurethane is placed in an N,N-dimethylacetamide solvent and stirred evenly to form a spinning solution. The photochromic spandex fiber based on the thiol-ene click reaction is obtained by electrospinning.
2. The photochromic spandex fiber based on the mercapto-ene click reaction according to claim 1, characterized in that: In the step (2), the mass ratio of 1-(8-bromooctyl)-3,3-dimethyl-2-methyleneindoline to 1-nitroso-2,7-dihydroxynaphthalene is 100:110-130.
3. The photochromic spandex fiber based on the mercapto-ene click reaction according to claim 1, characterized in that: The temperature of the cyclization reaction in step (2) is 20-40°C, and the reaction time is 6-12 h.
4. The photochromic spandex fiber based on the mercapto-ene click reaction according to claim 1, characterized in that: In the step (2), the mass ratio of the bromospirooxazine compound to potassium thioacetate is 100:55-80.
5. The photochromic spandex fiber based on mercapto-ene click reaction according to claim 1, characterized in that: The temperature of the nucleophilic substitution reaction in step (3) is 50-70°C, and the reaction time is 6-12 h.
6. The photochromic spandex fiber based on mercapto-ene click reaction according to claim 1, characterized in that: In the step (4), the mass ratio of 4,4'-diphenylmethane diisocyanate, polytetramethylene ether glycol, 1,4-butanediol and hydroxyethyl methacrylate is 40-60:100:3-6:2-4.
7. The photochromic spandex fiber based on mercapto-ene click reaction according to claim 1, characterized in that: In the step (5), the mass ratio of the solid content of the terminal olefin polyurethane emulsion to the mercapto spirooxazine compound is 100:5-25.
8. The photochromic spandex fiber based on mercapto-ene click reaction according to claim 1, characterized in that: The thiol-ene click reaction in step (5) is irradiated with ultraviolet light for 4-10 h at a reaction temperature of 50-70°C.