Splicing preparation method of stepwise temperature-sensitive hydrogel based on organic long afterglow material

Abstract

The stepwise temperature sensing hydrogel based on the organic long afterglow material is prepared by the following specific preparation method: a plurality of composite hydrogels with different temperature stimulus responses are cut and spliced, and then low-temperature freezing is carried out for 12-18 h, so that the stepwise temperature sensing hydrogel is obtained; the composite hydrogel with different temperature stimulus responses is obtained by adding PEG and PVA to water and long afterglow luminescent material in a weight ratio of 30%-40%, and then heating, stirring and circulating freezing, wherein the concentration of PVA in water is 7%-10%, and the percentage of long afterglow luminescent material in water is 2%-5%. The application is based on the self-healing characteristics of the hydrogel, the prepared flexible hydrogel with temperature stimulus response is cut and spliced, the hydrogel with stepwise temperature sensing is prepared, the hydrogel can be recycled, has excellent flexibility and stability, and greatly improves the intelligent application of the LPL material.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of application of organic long afterglow materials, and particularly relates to a splicing preparation method of a stepped temperature-sensitive hydrogel based on an organic long afterglow material. BACKGROUND

[0002] In recent years, long persistent luminescence (LPL) materials have attracted extensive attention due to their unique optical properties, particularly their potential applications in biological imaging, anti-counterfeiting, information storage, and other fields. Stimulus-responsive LPL materials exhibit great application potential by responding to external stimuli such as temperature, pressure, humidity, etc. Among them, temperature-stimulated LPL materials are particularly attractive because they can exhibit controllable long afterglow luminescence characteristics under specific temperature conditions, thus being suitable for temperature sensing and intelligent response in practical application scenarios.

[0003] In the development of temperature-stimulated LPL materials, host-guest doping strategies are widely used due to their low cost, structural diversity, and ease of large-scale preparation. However, the current development of temperature-stimulated LPL materials faces challenges in flexibility and processability, which limits their flexibility and diversity in practical applications. To overcome these limitations, we propose a strategy that combines LPL doped materials with hydrogels. Hydrogels are ideal carrier materials due to their lightweight, easy processing, good flexibility, and self-healing characteristics. SUMMARY

[0004] To overcome the above shortcomings, the present application provides a splicing preparation method of a stepped temperature-sensitive hydrogel based on an organic long afterglow material. By combining LPL materials with hydrogels, we prepared a composite hydrogel that not only has temperature response characteristics but also can achieve flexible multi-step temperature response through self-healing and splicing. This innovative strategy not only enhances the flexibility of the material but also expands the application potential of LPL materials in temperature detection and intelligent response systems. To achieve the above purpose, the technical solution adopted by the present application is as follows:

[0005] The splicing preparation method of the stepped temperature-sensitive hydrogel based on the organic long afterglow material is as follows: cut and splice multiple groups of composite hydrogels with different temperature stimulation responses, then freeze at low temperature for 12-18 hours to obtain the stepped temperature-sensitive hydrogel.

[0006] The composite hydrogel with different temperature stimulation responses is obtained by adding PEG and PVA to water and long afterglow luminescent materials in a weight ratio of 30%-40%, respectively, wherein the concentration of PVA in water is 7-10%, and the percentage of long afterglow luminescent materials in water is 2-5%.

[0007] Further optimization, the specific preparation method of the composite hydrogel is as follows: the organic long afterglow luminescent material, PVA and PEG are added to deionized water for heating and stirring, a white emulsion is prepared, and then poured into a mold, and the composite hydrogel with temperature stimulation response is obtained through cyclic freezing and thawing.

[0008] Further optimization, the heating temperature is 90-100 DEG C, and the stirring time is 3-5 h.

[0009] Further optimization, the freezing and thawing time is 12-18 h, and the cyclic freezing and thawing times are 3-5 times.

[0010] Further optimization, the long afterglow luminescent material comprises a host material and a guest material, the host material is diphenylamine, phenyl benzoate and triphenylphosphine, the guest material is N,N'-diphenyl-N,N'-(1-naphthyl)-1,1'-biphenyl-4,4'-diamine, N,N'-diphenyl benzidine and N,N'-diphenyl-N,N'-bis(4-methylphenyl)-4,4'-biphenyldiamine, and the following three kinds of doping are carried out: diphenylamine and N,N'-diphenyl-N,N'-(1-naphthyl)-1,1'-biphenyl-4,4'-diamine, phenyl benzoate and N,N'-diphenyl-N,N'-bis(4-methylphenyl)-4,4'-biphenyldiamine, triphenylphosphine and N,N'-diphenyl benzidine.

[0011] Further optimization, the number of the plurality of groups of composite hydrogels with different temperature stimulation responses is three groups.

[0012] The beneficial effects of the present application are:

[0013] 1. By selecting an organic long afterglow luminescent material with a suitable melting point, the composite hydrogel is combined to prepare a flexible hydrogel with temperature stimulation response;

[0014] 2. Based on the self-healing characteristics of the hydrogel, the prepared plurality of groups of flexible hydrogels with temperature stimulation response are cut and spliced to prepare a hydrogel with stepwise temperature sensing;

[0015] 3. The temperature detection system of the present application can be flexibly spliced according to requirements;

[0016] 4. The stepwise temperature sensing hydrogel of the present application can be recycled, greatly improving its practical application prospect. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is a schematic diagram of the temperature stimulation response mechanism of the stepwise temperature sensing long afterglow in the present application;

[0018] Figure 2 is a performance display diagram of the prepared stepwise temperature sensing long afterglow in the present application;

[0019] Figure 3 is a schematic diagram of the preparation of the stepwise temperature-sensitive hydrogel in the present application;

[0020] Figure 4 is a performance display diagram of the stepwise temperature-sensitive hydrogel 1 prepared in Example 4 in the present application;

[0021] Figure 5 is a performance display diagram of the stepwise temperature-sensitive hydrogel 2 prepared in Example 5 in the present application;

[0022] Figure 6 is a performance display diagram of the stepwise temperature-sensitive hydrogel 3 prepared in Example 6 in the present application;

[0023] Figure 7 is a scanning electron microscope diagram of the stepwise temperature-sensitive hydrogel 3 prepared in Example 6 in the present application;

[0024] Figure 8 is a performance display diagram of the recycling performance of the stepwise temperature-sensitive hydrogel 3 prepared in Example 6 in the present application;

[0025] Figure 9 is a water stability and tensile performance display diagram of the stepwise temperature-sensitive hydrogel 3 prepared in Example 6 in the present application. DETAILED DESCRIPTION

[0026] In order to enable a clearer understanding of the above-mentioned purposes, features and advantages of the present application, the present application will be described in detail below in combination with specific embodiments, the following embodiments are implemented on the premise of the technical scheme of the present application, and detailed implementation modes and specific operation processes are given, but the present application can also be implemented in other ways different from those described herein, and therefore the protection scope of the present application is not limited to the following embodiments.

[0027] In the present application, the purchase manufacturers of N,N'-diphenyl-N,N'-(1-naphthyl)-1,1'-biphenyl-4,4'-diamine (NPD) and N,N'-diphenylphenylamine (NDPB) are: Saen Chemical Technology Co., Ltd. (purity: 98%-99%); the purchase manufacturers of triphenylphosphine (TPP), benzyl benzoate (BP) and polyvinyl alcohol (PVA, M.W. 105000) are: Anhui Zesheng Technology Co., Ltd. N,N'-diphenyl-N,N'-bis(4-methylphenyl)-4,4'-biphenyldiamine (p-TPD) and polyethylene glycol (PEG 4000) are purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.

[0028] The instruments and models involved in the following examples are as follows:

[0029] Ocean Optics multi-band spectrometer, FlexSEM 1000 scanning electron microscope, F-7000 fluorescence spectrometer;

[0030] Room temperature: 20~25 ℃.

[0031] The power of the ultraviolet lamp in the following examples is 20 W (365 nm).

[0032] The splicing preparation method of the stepped temperature-sensitive hydrogel based on the organic long afterglow material is prepared by adding PEG and PVA into water and long afterglow luminescent material at a weight ratio of 30%-40%, wherein the concentration of PVA in water is 7-10%, and the percentage of long afterglow luminescent material in water is 2-5%. A plurality of composite hydrogels with different temperature stimulation responses are prepared. The plurality of composite hydrogels with different temperature stimulation responses are cut and spliced, and then low-temperature freezing is performed for 12-18 h to obtain the stepped temperature-sensitive hydrogel.

[0033] The long afterglow luminescent material comprises a host material and a guest material. The host material is diphenylamine (DPA), phenyl benzoate (PB) and triphenylphosphine (TPP). The guest material is N,N'-diphenyl-N,N'-(1-naphthyl)-1,1'-biphenyl-4,4'-diamine (NPD), N,N'-diphenylbenzidine (NDPB) and N,N'-diphenyl-N,N'-bis(4-methylphenyl)-4,4'-biphenyldiamine (p-TPD). The following three kinds of doping are performed: diphenylamine and N,N'-diphenyl-N,N'-(1-naphthyl)-1,1'-biphenyl-4,4'-diamine, phenyl benzoate and N,N'-diphenyl-N,N'-bis(4-methylphenyl)-4,4'-biphenyldiamine, triphenylphosphine and N,N'-diphenylbenzidine.

[0034] Figure 1 It is a schematic diagram of the temperature stimulation response mechanism of the stepped temperature-sensitive long afterglow in the present application. As shown in the figure, when the temperature reaches the melting point of the host material, the host in the long afterglow luminescent material cannot provide a good rigid environment, thereby causing it to lose the afterglow performance.

[0035] Figure 2 It is a performance display diagram of the stepped temperature-sensitive long afterglow prepared in the present application. As shown in the figure, the doping materials DPA:NDPB, BP:p-TPD and TPP:NPD have good afterglow performance, and there is a color difference between the three doping materials, which is conducive to the identification of the temperature-sensitive hydrogel when measuring the temperature.

[0036] The specific preparation method of the three temperature-sensitive hydrogels of the doping materials DPA:NDPB, BP:p-TPD and TPP:NPD is as follows.

[0037] Example 1

[0038] Preparation of 55℃ thermo-sensitive hydrogel: 1.00 g of DPA:NDPB organic long afterglow luminescent material, 2.40 g of PVA and 0.96 g of PEG were added to 30 mL of deionized water, and then stirred at 95 ℃ for 3 h to prepare a white emulsion. The emulsion was poured into a mold, and then subjected to cyclic freezing and thawing four times to obtain a 55℃ thermo-sensitive hydrogel.

[0039] Example 2

[0040] Preparation of 75℃ thermo-sensitive hydrogel: 1.00 g of BP:p-TPD organic long afterglow luminescent material, 2.40 g of PVA and 0.96 g of PEG were added to 30 mL of deionized water, and then stirred at 95 ℃ for 3 h to prepare a white emulsion. The emulsion was poured into a mold, and then subjected to cyclic freezing and thawing four times to obtain a 75℃ thermo-sensitive hydrogel.

[0041] Example 3

[0042] Preparation of 80℃ thermo-sensitive hydrogel: 1.00 g of TPP:NPD organic long afterglow luminescent material, 2.40 g of PVA and 0.96 g of PEG were added to 30 mL of deionized water, and then stirred at 95 ℃ for 3 h to prepare a white emulsion. The emulsion was poured into a mold, and then subjected to cyclic freezing and thawing four times to obtain a 80℃ thermo-sensitive hydrogel.

[0043] Any two or three groups of the three groups of thermo-sensitive hydrogels prepared in Examples 1-3 can be spliced to obtain different stepwise thermo-sensitive hydrogels, and the specific preparation method is as follows in Examples 4-6.

[0044] Example 4

[0045] Splicing preparation of 55℃ stepwise thermo-sensitive hydrogel: the thermo-sensitive hydrogels prepared in Examples 1 and 3 were cut and spliced in a close state, and then frozen for 12-18 h to obtain stepwise thermo-sensitive hydrogel 1.

[0046] Figure 4 It is a performance display diagram of the stepwise thermo-sensitive hydrogel 1 prepared in Example 4 of the present application, and from the diagram, it can be seen that the thermo-sensitive hydrogel 1 can occur DPA:NDPB regional quenching at 55℃, realizing clear temperature discrimination.

[0047] Example 5

[0048] Splicing preparation of 75℃ stepwise thermo-sensitive hydrogel: the thermo-sensitive hydrogels prepared in Examples 2 and 3 were cut and spliced in a close state, and then frozen for 12-18 h to obtain stepwise thermo-sensitive hydrogel 2.

[0049] Figure 5 is the performance display diagram of the stepwise temperature-sensitive hydrogel 2 prepared in Example 5 of the present application, and it can be seen from the diagram that the temperature-sensitive hydrogel 2 can occur BP:p-TPD region quenching at 75℃, realizing clear temperature discrimination.

[0050] Example 6

[0051] Splicing preparation of 55℃ and 75℃ stepwise temperature-sensitive hydrogel: the temperature-sensitive hydrogels prepared in Examples 1, 2 and 3 are sheared, and spliced in a close state and frozen for 12-18h, to obtain the stepwise temperature-sensitive hydrogel 3.

[0052] Figure 6 is the performance display diagram of the stepwise temperature-sensitive hydrogel 3 prepared in Example 6 of the present application. As can be seen from the diagram, the temperature-sensitive hydrogel 3 has double-step temperature-sensitive performance, and can occur DPA:NDPB region quenching at 55℃ and BP:p-TPD region quenching at 75℃. At the same time, due to the different afterglow colors of the long afterglow material, clear temperature discrimination is realized. Figure 7 is the scanning electron microscope diagram of the stepwise temperature-sensitive hydrogel 3 prepared in Example 6 of the present application. As can be seen from the diagram, the large number of pores existing in the gel are conducive to the uniform dispersion of the LPL material, so that the temperature-sensitive hydrogel still has uniform luminescence performance under deformation. Figure 8 is the cycle use performance display diagram of the stepwise temperature-sensitive hydrogel 3 prepared in Example 6 of the present application. As can be seen from the diagram, the gel has good cycle use performance and can have excellent application potential. Figure 9 is the water stability and tensile performance display diagram of the stepwise temperature-sensitive hydrogel 3 prepared in Example 6 of the present application. As can be seen from the diagram, the presence of the gel well protects the LPL material, so that it has good stability in water, and still has uniform luminescence performance under stretching. These excellent properties show that the stepwise temperature-sensitive hydrogel has excellent flexibility and stability, greatly improving the intelligent application of the LPL material.

[0053] The above shows and describes the main features, use method, basic principle and advantages of the present application. It should be understood by those skilled in the art that the present application is not limited by the above examples, and the above examples and descriptions in the specification are only to illustrate the principle of the present application. Without departing from the spirit and scope of the present application, the present application can be variously changed and improved according to the actual situation, and these changes and improvements all fall within the scope of the claimed present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A method for splicing stepwise temperature-sensitive hydrogels based on organic long-persistent materials, characterized in that, The specific preparation method is as follows: a plurality of groups of composite hydrogels with different temperature stimulus responses are cut and spliced, and then are frozen at low temperature for 12-18 h, so that the ladder type temperature sensitive hydrogel is obtained. The specific preparation method of the composite hydrogel is as follows: the organic long afterglow luminescent material, PVA and PEG are added to deionized water for heating and stirring, a white emulsion is prepared, and then is poured into a mold, and the composite hydrogel with temperature stimulus response is obtained through cyclic freezing and thawing, wherein the mass concentration of PVA in water is 7-10%, and the mass percentage of the long afterglow luminescent material in water is 2-5%. The long afterglow luminescent material comprises a host material and a guest material, the host material is diphenylamine, phenyl benzoate and triphenylphosphine, and the guest material is N,N'-diphenyl-N,N'-(1-naphthyl)-1,1'-biphenyl-4,4'-diamine, N,N'-diphenyl benzidine and N,N'-diphenyl-N,N'-bis(4-methylphenyl)-4,4'-biphenyl diamine, and the following three kinds of doping are carried out: diphenylamine and N,N'-diphenyl-N,N'-(1-naphthyl)-1,1'-biphenyl-4,4'-diamine, phenyl benzoate and N,N'-diphenyl-N,N'-bis(4-methylphenyl)-4,4'-biphenyl diamine, triphenylphosphine and N,N'-diphenyl benzidine.

2. The splicing preparation method of the stepwise temperature-sensitive hydrogel based on the organic long afterglow material according to claim 1, characterized in that, The heating temperature is 90-100 DEG C, and the stirring time is 3-5 h.

3. The splicing preparation method of the organic long afterglow material-based stepwise temperature-sensitive hydrogel according to claim 1, characterized in that, The freezing and thawing time is 12-18 h, and the cyclic freezing and thawing times are 3-5 times.

4. The method for preparing a stepped temperature-sensitive hydrogel based on organic long afterglow materials as described in claim 1, characterized in that, The number of the plurality of groups of composite hydrogels with different temperature stimulus responses comprises three groups.

Images