Fluorescent nylon material as well as preparation method and application thereof

Abstract

The invention discloses a fluorescent nylon material and a preparation method and application thereof, and relates to the technical field of high polymer material preparation, the structural formula of the fluorescent nylon material comprises a structural unit derived from 1, 3, 6, 8-tetraaminopyrene and a structural unit derived from a nylon monomer. According to the fluorescent nylon material provided by the invention, the monomer compound and the nylon monomer are copolymerized, and the fluorescent compound can be uniformly dispersed in a nylon matrix, so that the nylon material is endowed with fluorescent performance. The fluorescent nylon material has the characteristics of high brightness, good stability, rich color and the like; the fluorescence quantum yield can reach 85% or above; the fluorescent property is excellent, and bright-colored fluorescence can be emitted under the excitation of ultraviolet light; the nylon has physical and mechanical properties similar to those of common nylon. According to the fluorescent nylon material and the preparation method thereof provided by the invention, a new possibility is provided for expanding the application of the nylon material in the special field.

Description

Technical Field

[0001] This invention relates to the field of polymer material preparation technology, and more specifically, to a fluorescent nylon material, its preparation method, and its application. Background Technology

[0002] Traditional nylon materials do not fluoresce under ultraviolet light, thus limiting their application in certain specialized fields requiring fluorescence indication. Typically, fluorescent compounds are added to nylon resin, followed by melt blending and extrusion molding to produce fluorescent nylon materials. However, blending methods often fail to achieve high dispersion, or the fluorescent compounds may degrade or decompose during melt blending.

[0003] The fluorescence quantum yield of fluorescent nylon materials is typically influenced by various factors, such as molecular structure, aggregation state, and environmental conditions. While there are methods to enhance the fluorescence quantum yield of fluorescent nylon materials, these include: optimizing molecular structure: designing molecular structures with high fluorescence quantum yields can improve the fluorescence quantum yield of fluorescent nylon materials. For example, molecules with larger conjugated systems can be selected to increase the probability of electronic transitions and the efficiency of fluorescence emission. Reducing aggregation states: Fluorescent nylon materials are often prone to aggregation, which reduces the fluorescence quantum yield. To reduce aggregation states, methods such as using surfactants, polymer additives, or changing the synthesis conditions of the nylon material can be employed. Adding luminescent agents: adding luminescent agents to fluorescent nylon materials can enhance their fluorescence quantum yield. For example, rare earth elements or other luminescent agents with high fluorescence quantum yields can be added. Increasing ambient temperature: increasing ambient temperature can promote molecular motion in fluorescent nylon materials, thereby increasing the probability of electronic transitions and the efficiency of fluorescence emission. Changing environmental conditions: altering environmental conditions (such as humidity, pressure, atmosphere, etc.) can affect the fluorescence quantum yield of fluorescent nylon materials. For example, the fluorescence quantum yield of fluorescent nylon materials may be increased in the presence of an inert gas or under low humidity conditions. However, no specific fluorescent nylon material currently exhibits a high quantum yield. Summary of the Invention

[0004] To address the problems existing in the prior art, this invention provides a fluorescent nylon material, its preparation method, and its applications. This invention provides a blue-green fluorescent nylon material with high quantum yield, possessing the excellent mechanical properties of nylon itself, which can greatly satisfy its application in flexible displays.

[0005] One of the objectives of this invention is to provide a fluorescent nylon material.

[0006] The fluorescent nylon material of the present invention comprises a structural formula derived from... Structural units and structural units derived from nylon monomers.

[0007] In a preferred embodiment of the present invention:

[0008] The fluorescent nylon material is derived from... The content of the structural unit is 0.005-5 wt%, preferably 0.01-2 wt%, and more preferably 0.01-0.5 wt%.

[0009] In a preferred embodiment of the present invention:

[0010] The structural formula of the structural unit derived from nylon monomer is:

[0011]

[0012] Wherein, R1, R2, and R3 may be the same or different, R1, R2, and R4 may be the same or different, and R3 and R4 are different, and are independently one of C4-C18 aromatic hydrocarbon group, C4-C18 straight-chain hydrocarbon group, and C4-C18 branched alkane group; 0≤x≤1, 0≤y≤1, 0≤z≤1, x+y+z=1; preferably,

[0013] R1 is -(CH2)4-, -(CH2)6-, or -(CH2) 10 One of them; and / or,

[0014] R2 is one of -(CH2)2-, -(CH2)4-, or -(CH2)8-; and / or,

[0015] R3 is -(CH2)5- or -(CH2) 10 -; and / or,

[0016] R4 is -(CH2)5- or -(CH2) 10 -

[0017] In a preferred embodiment of the present invention:

[0018] The relative viscosity of the fluorescent nylon material is 1.6-4.0, preferably 2.2-3.0.

[0019] A second objective of this invention is to provide a method for preparing fluorescent nylon material as described in one objective of this invention.

[0020] The method for preparing the fluorescent nylon material of the present invention includes:

[0021] The fluorescent nylon material is prepared by polymerizing and optionally polycondensing raw materials, including monomer compounds, nylon monomers, optionally initiators and / or additives, under a protective gas atmosphere and by heating.

[0022] In a preferred embodiment of the present invention:

[0023] The weight of the monomer compound is 0.01-10 wt% of the total weight of the monomer compound and the nylon monomer, preferably 0.1-2 wt%, more preferably 0.1-0.5 wt%; and / or,

[0024] When the initiator is included, the weight ratio of the initiator to the nylon monomer is (0.001-20):100, preferably (1-3):100; and / or,

[0025] When the additive is included, the weight ratio of the additive to the nylon monomer is (0.01-10):100, preferably (0.01-3):100.

[0026] In the method of this invention, the amount of monomer compound added has a significant impact on the fluorescence properties of the nylon material. By adjusting the amount of monomer compound, the fluorescence properties of nylon can be precisely controlled. Furthermore, to obtain even better fluorescence effects, the nylon material can be surface-treated or other functional additives can be added.

[0027] In a preferred embodiment of the present invention:

[0028] The monomeric compound is

[0029] In a preferred embodiment of the present invention:

[0030] The nylon monomer is at least one of caprolactam, laurolactam, hexamethylenediamine, aminocaproic acid, aminoundecanoic acid, aminododecanoic acid, nylon 66 salt, nylon 610 salt, and nylon 612 salt.

[0031] In a preferred embodiment of the present invention:

[0032] The initiator is water.

[0033] Taking water-induced ring-opening of nylon 6 as an example, the preparation method of the present invention can specifically adopt the following scheme:

[0034] The monomer compound, nylon 6 monomer caprolactam, and initiator water are added to the reactor, and an inert gas is introduced to remove oxygen for 30 minutes. The temperature is raised to 180-260℃ to carry out the polymerization reaction, and the reaction pressure is controlled at 1-20 atmospheres for 0.5-7 hours. Then the pressure is slowly reduced while maintaining the reaction temperature at 180-260℃. To further increase the molecular weight of polyamide, polycondensation is carried out under high vacuum. The vacuum degree is gradually controlled to below 200 Pa, and the reaction is continued for 0.5 hours.

[0035] In a preferred embodiment of the present invention:

[0036] To regulate the mechanical and thermal properties of the fluorescent nylon material, various additives can be added in situ for copolymerization. The additives are maleic anhydride copolymers and / or imidazolic anhydride copolymers, preferably maleic anhydride copolymers, more preferably at least one of maleic anhydride styrene copolymers, maleic anhydride vinyl ether copolymers, and maleic anhydride olefin copolymers, and even more preferably maleic anhydride styrene copolymers and / or maleic anhydride-1-hexene copolymers. By adding additives such as maleic anhydride copolymers and imidazolic anhydride copolymers, the molecular weight of the fluorescent nylon material can be increased, and its fluorescent properties can be enhanced.

[0037] In a preferred embodiment of the present invention:

[0038] The protective gas is nitrogen; and / or,

[0039] The polymerization reaction is carried out at a temperature of 180-260℃, and / or for a reaction time of 0.5-7 h, and / or at a reaction pressure of 0.1-20 atmospheres; and / or

[0040] The vacuum degree of the polycondensation reaction is below 200 Pa. The reaction time of the polycondensation reaction is not particularly limited. Those skilled in the art can extend or shorten the reaction time according to the molecular weight requirements of the final product.

[0041] A third objective of this invention is to provide an application of a fluorescent nylon material as described in one objective of this invention or a fluorescent nylon material prepared by the method described in another objective of this invention in a flexible display.

[0042] The present invention has the following advantages:

[0043] The fluorescent nylon material provided by this invention uses a monomer compound copolymerized with nylon monomers. The fluorescent compound can be uniformly dispersed in the nylon matrix, thereby endowing the nylon material with fluorescent properties. The fluorescent nylon material of this invention features high brightness, good stability, and rich colors; its fluorescence quantum yield can reach over 85%; it exhibits excellent fluorescence properties, emitting bright fluorescence under ultraviolet light excitation; and it possesses physical and mechanical properties similar to ordinary nylon, such as high strength, abrasion resistance, and corrosion resistance. The preparation method of this invention is simple, feasible, and suitable for large-scale production. Therefore, the fluorescent nylon material and its preparation method provided by this invention offer new possibilities for expanding the application of nylon materials in specialized fields. Attached Figure Description

[0044] Figure 1 This is the fluorescence spectrum of the fluorescent nylon material prepared in Example 1 of the present invention. Detailed Implementation

[0045] The following provides a detailed description of specific embodiments of the present invention. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the invention. The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values; these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0046] The raw materials used in the embodiments and comparative examples of this invention are all commercially available products.

[0047] The test methods in the embodiments and comparative examples of this invention are as follows:

[0048] Optical performance testing was performed using an FLS 980 steady-state and transient fluorescence spectrometer from Edinburgh, UK. Xenon lamps were used as the excitation source for steady-state fluorescence spectroscopy, LED lasers or supercontinuum lasers were used for fluorescence lifetime testing, and microsecond lamps were used for both steady-state and transient phosphorescence spectroscopy, with gated operation. P928P PMT detectors were used for all tests. Total photoluminescence quantum yield and phosphorescence quantum yield were measured using the FLS 980 with an integrating sphere accessory. The excitation wavelength for steady-state fluorescence / phosphorescence spectroscopy, phosphorescence lifetime, and total / phosphorescence quantum yield tests was 365 nm.

[0049] Tensile strength was measured according to ASTM D638 method at a tensile speed of 50 mm / min; elongation at break is the ratio of displacement at break to original length, expressed as a percentage.

[0050] Relative viscosity test: Weigh 0.25g of sample and place it in a 25ml volumetric flask. Add concentrated sulfuric acid (until the mark). After the sample is completely dissolved, add concentrated sulfuric acid to the mark in the volumetric flask, then shake well for measurement. Pipette 10ml of the prepared solution into an Ubbelohde viscometer (4-1.0-1.1). Vertically install the viscometer in a constant temperature water bath at 25±0.5℃ for 20min. The time it takes for the solution to flow through both marks on the viscometer is the flow time. Measure each sample three times (with an error not exceeding ±0.2s) and take the average value.

[0051]

Example 1

[0052] 130g of caprolactam and 20g of aminocaproic acid were added to a 500mL three-necked flask. Nitrogen gas was purged for 30 minutes to remove oxygen. Then, 0.15g of tetraaminopyrene was added. The reactor was heated to 260℃ to carry out a hydrolysis ring-opening reaction. After stirring for about 3 hours, a vacuum was slowly applied to maintain the reaction temperature at around 230℃. The low-vacuum reaction was carried out for about 1 hour. After excess water was removed, a high-vacuum reaction was initiated, and the vacuum degree was further reduced to below 200Pa. A polycondensation reaction was carried out for 0.5 hours. The resulting product was fluorescent nylon material, whose structural unit derived from the nylon monomer was nylon 6 (-NH-(CH2)5-CO-). The fluorescence emission was measured at 490nm, with a quantum yield of 88.47% and a relative viscosity of 2.9.

[0053]

Example 2

[0054] 130g of caprolactam and 20g of aminocaproic acid were added to a 500mL three-necked flask. Nitrogen gas was purged for 30 minutes to remove oxygen. Then, 0.015g of tetraaminopyrene was added. The reactor was heated to 260℃ to carry out a hydrolysis ring-opening reaction. After stirring for about 3 hours, a vacuum was slowly applied to maintain the reaction temperature at around 230℃. The low-vacuum reaction was carried out for about 1 hour. After excess water was removed, a high-vacuum was applied, and the vacuum degree was further reduced to below 200Pa. A polycondensation reaction was carried out for 0.5 hours. The resulting product was fluorescent nylon material, whose structural unit derived from the nylon monomer was nylon 6 (-NH-(CH2)5-CO-). The fluorescence emission was measured at 488nm, the quantum yield was 89.23%, and the relative viscosity was 2.7.

[0055]

Example 3

[0056] 130g of caprolactam and 20g of aminocaproic acid were added to a 500mL three-necked flask. Nitrogen gas was purged for 30 minutes to remove oxygen. Then, 1.5g of tetraaminopyrene was added. The reactor was heated to 260℃ to carry out a hydrolysis ring-opening reaction. After stirring for about 3 hours, a vacuum was slowly applied to maintain the reaction temperature at around 230℃. The low-vacuum reaction was carried out for about 1 hour. After excess water was removed, a high-vacuum was applied, and the vacuum degree was further reduced to below 200Pa. A polycondensation reaction was carried out for 0.5 hours. The resulting product was fluorescent nylon material, whose structural unit derived from the nylon monomer was nylon 6 (-NH-(CH2)5-CO-). The fluorescence emission was measured at 481nm, the quantum yield was 85.01%, and the relative viscosity was 2.2.

[0057]

Example 4

[0058] 130g of laurolactam and 20g of aminododecanoic acid were added to a 500mL three-necked flask. Nitrogen gas was bubbled through the flask for 30 minutes to remove oxygen. Then, 1.05g of tetraaminopyrene was added. The reactor was heated to 260℃ for a hydrolysis ring-opening reaction. After stirring for approximately 3 hours, a vacuum was slowly applied to maintain the reaction temperature at around 230℃. This low-vacuum reaction lasted for about 1 hour. Once excess water was removed, a high-vacuum reaction was initiated, further reducing the vacuum to below 200Pa. A polycondensation reaction was then carried out for 0.5 hours. The resulting product was fluorescent nylon material, whose structural unit derived from the nylon monomer is... The fluorescence emission was measured at 485 nm, the quantum yield was 86.24%, and the relative viscosity was 2.8.

[0059]

Example 5

[0060] 150g of caprolactam and 6g of deionized water were added to a 500mL stainless steel reactor. Nitrogen gas was introduced for deoxygenation for 30 minutes. Then, 0.03g of tetraaminopyrene was added. The reactor was heated to 260℃, and the pressure was controlled at 3-5 atmospheres for hydrolysis and ring-opening reaction. After about 3 hours, the pressure was slowly reduced to atmospheric pressure, and then gradually evacuated, maintaining the reaction temperature at around 230℃. The low-vacuum reaction lasted about 1 hour. After excess water was removed, a high-vacuum reaction was initiated, further reducing the vacuum to below 200Pa for condensation polymerization for 0.5 hours. The resulting product was fluorescent nylon material, derived from the nylon monomer with the structural unit nylon 6 (-NH-(CH2)5-CO-). Its fluorescence emission was measured at 490nm, with a quantum yield of 86.91%. The relative viscosity was 3.4.

[0061]

Example 6

[0062] 130g of caprolactam, 0.5g of maleic anhydride-styrene copolymer (Mn=5000, PDI=1.1), and 20g of aminocaproic acid were added to a 500mL three-necked flask. Nitrogen gas was bubbled through the flask for 30 minutes to remove oxygen. Then, 0.15g of tetraaminopyrene was added. The reactor was heated to 260℃ for a ring-opening reaction. After stirring for approximately 3 hours, a vacuum was slowly applied to maintain the reaction temperature at around 230℃. The low-vacuum reaction lasted for approximately 1 hour. Once excess water was removed, a high-vacuum reaction was initiated, further reducing the vacuum to below 200Pa. A polycondensation reaction was then carried out for 0.5 hours. The resulting product was fluorescent nylon material, derived from the nylon monomer with the structural unit nylon 6 (-NH-(CH2)5-CO-). The fluorescence emission was measured at 490nm, with a quantum yield of 83.03%. The relative viscosity was 3.4.

[0063] Comparative Example 1

[0064] 130g of caprolactam and 20g of aminocaproic acid were added to a 500mL three-necked flask. Nitrogen gas was purged for 30 minutes to remove oxygen. The reactor was heated to 260℃ to carry out a hydrolysis ring-opening reaction. After stirring for about 3 hours, a vacuum was slowly applied to maintain the reaction temperature at around 230℃. The low-vacuum reaction lasted for about 1 hour. After excess water was removed, a high-vacuum was applied, and the vacuum was further reduced to below 200Pa to carry out a polycondensation reaction for 0.5 hours. The nylon material was then discharged. The fluorescence emission was measured at 420nm, the quantum yield was 2.1%, and the relative viscosity was 3.3.

[0065] Comparative Example 2

[0066] 130g of caprolactam and 20g of aminocaproic acid were added to a 500mL three-necked flask. 0.15g of 1-aminopyrene was added, and nitrogen gas was bubbled through for 30 minutes to remove oxygen. The reactor was heated to 260℃ for a hydrolysis ring-opening reaction. After stirring for about 3 hours, a vacuum was slowly applied to maintain the reaction temperature at around 230℃. The low-vacuum reaction lasted for about 1 hour. Once excess water was removed, a high-vacuum reaction was initiated, further reducing the vacuum to below 200Pa for a condensation polymerization reaction for 0.5 hours. The resulting material was nylon. The fluorescence emission was measured at 420nm, the quantum yield was 47.31%, and the relative viscosity was 2.8.

[0067] The tensile strength of the materials prepared in the above embodiments and comparative examples was tested, and the test results are shown in Table 1 below.

[0068] Table 1

[0069] project relative viscosity Tensile strength (MPa) Elongation at break (%) Example 1 2.9 51.7 42 Example 2 2.7 48.1 37 Example 3 2.2 47.8 38 Example 4 2.8 51.6 71 Example 5 3.4 60.1 45 Example 6 3.4 59.2 32 Comparative Example 1 3.3 42.5 25 Comparative Example 2 2.8 59.1 15

[0070] As can be seen from Table 1 and the fluorescence test results, compared with Comparative Example 1, the fluorescent nylon materials of Examples 1-6 of the present invention can have excellent fluorescence performance while ensuring mechanical properties, and the fluorescence quantum yield can reach more than 85%. Compared with Comparative Example 2, the fluorescence quantum yield of Example 1 of the present invention is significantly improved, indicating that a single pyrene structure cannot achieve the high fluorescence quantum yield effect of the present invention.

Claims

1. A fluorescent nylon material, characterized in that the structural formula of the fluorescent nylon material includes those derived from... Structural units and structural units derived from nylon monomers.

2. The fluorescent nylon material according to claim 1, characterized in that: The fluorescent nylon material is derived from... The content of the structural unit is 0.005-5 wt%, preferably 0.01-2 wt%, and more preferably 0.01-0.5 wt%.

3. The fluorescent nylon material according to claim 1, characterized in that: The structural formula of the structural unit derived from nylon monomer is: Wherein, R1, R2, and R3 may be the same or different, R1, R2, and R4 may be the same or different, and R3 and R4 are different, and are independently one of C4-C18 aromatic hydrocarbon group, C2-C18 straight-chain hydrocarbon group, and C4-C18 branched alkane group; 0≤x≤1, 0≤y≤1, 0≤z≤1, x+y+z=1; preferably, R1 is -(CH2)4-, -(CH2)6-, or -(CH2) 10 One of them; and / or, R2 is one of -(CH2)2-, -(CH2)4-, or -(CH2)8-; and / or, R3 is -(CH2)5- or -(CH2) 10 -; and / or, R4 is -(CH2)5- or -(CH2) 10 - 4. The fluorescent nylon material according to any one of claims 1-3, characterized in that: The relative viscosity of the fluorescent nylon material is 1.6-4.0, preferably 2.2-3.

0.

5. A method for preparing a fluorescent nylon material as described in any one of claims 1-4, the method comprising: The fluorescent nylon material is prepared by polymerizing and optionally polycondensing raw materials, including monomer compounds, nylon monomers, optionally initiators and / or additives, under a protective gas atmosphere and by heating.

6. The method according to claim 5, characterized in that: The weight of the monomer compound is 0.01-10 wt% of the total weight of the monomer compound and the nylon monomer, preferably 0.1-2 wt%, more preferably 0.01-0.5 wt%; and / or, When the initiator is included, the weight ratio of the initiator to the nylon monomer is (0.001-20):100, preferably (1-3):100; and / or, When the additive is included, the weight ratio of the additive to the nylon monomer is (0.01-10):100, preferably (0.01-3):

100.

7. The method according to claim 5, characterized in that: The monomeric compound is 8. The method according to claim 5, characterized in that: The nylon monomer is at least one of caprolactam, laurolactam, hexamethylenediamine, aminocaproic acid, aminoundecanoic acid, aminododecanoic acid, nylon 66 salt, nylon 610 salt, and nylon 612 salt.

9. The method according to claim 5, characterized in that: The initiator is water.

10. The method according to claim 5, characterized in that: The additive is a maleic anhydride copolymer and / or a tannin copolymer, preferably a maleic anhydride copolymer, more preferably, the maleic anhydride copolymer is at least one of maleic anhydride styrene copolymer, maleic anhydride vinyl ether copolymer, and maleic anhydride olefin copolymer, and even more preferably maleic anhydride styrene copolymer and / or maleic anhydride-1-hexene copolymer.

11. The method according to claim 5, characterized in that: The protective gas is nitrogen; and / or, The polymerization reaction is carried out at a temperature of 180-260℃, and / or for a reaction time of 0.5-7 h, and / or at a reaction pressure of 0.1-20 atmospheres; and / or The vacuum degree of the polycondensation reaction is below 200 Pa.

12. The application of a fluorescent nylon material as described in any one of claims 1-4 or a fluorescent nylon material prepared by the method as described in any one of claims 5-11 in a flexible display.

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