CN110591035A - A kind of fast self-healing polyurethane elastomer with upconversion fluorescence response and preparation method thereof - Google Patents

Abstract

The invention relates to a fast self-healing polyurethane elastomer with up-conversion fluorescence response and a preparation method thereof. The preparation method comprises: dissolving rare earth chloride in a mixed solvent formed by mixing oleic acid and octadecene, and then sequentially Taking sodium hydroxide-methanol solution and ammonium fluoride-methanol solution and mixing them into a mixed solvent in which rare earth chlorides are dissolved to carry out the reaction, filtering after completion of the reaction, washing and drying the filtered precipitate to obtain up-conversion fluorescent particles; Diaminodiphenyldithiol is dissolved in an organic solvent, mixed with polyurethane prepolymer and up-conversion fluorescent particles, and degassed under vacuum, and finally the degassed mixture is cast in a mold for reaction. In the present invention, the up-conversion fluorescent material is compounded with the self-healing polyurethane system, which can not only realize the healing/self-healing of the polymer material, but also introduce the external fluorescent light stimulation response, thereby obtaining a self-healing system with multiple fluorescent responses. Healing optics.

Description

A fast self-healing polyurethane elastomer with upconversion fluorescence response and its preparation preparation method

technical field

The invention relates to the technical field of materials, in particular to a fast self-healing polyurethane elastomer with up-conversion fluorescence response and a preparation method thereof.

Background technique

Upconversion fluorescent material is a kind of anti-Stoke light-emitting material, which can emit high-energy short-wave radiation under the excitation of low-energy long-wave radiation. Compared with other fluorescent materials, upconversion fluorescent materials have the advantages of sharp emission peak, wide emission spectrum, good thermal stability, non-toxicity, cheap and easy-to-obtain excitation light source (ultraviolet and near-infrared laser), and good chemical stability. New optical devices, anti-counterfeiting technology, information storage and hiding fields have shown good application prospects.

However, the current optical devices based on up-conversion fluorescence generate microcracks in the process of molding, processing and use, and these microcracks will affect the service life of the optical device.

If the self-healing material can be effectively combined with up-conversion fluorescence, this problem will be greatly improved, so that the self-healing material not only has excellent healing properties, but also has the ability to respond to light, making it different from ordinary ones. The polyurethane self-healing material can provide a new solution for the construction of novel fluorescence-responsive self-healing optical devices.

SUMMARY OF THE INVENTION

In view of the above problems, a fast self-healing polyurethane elastomer with up-conversion fluorescence response and a preparation method thereof are now provided, aiming to provide a fast self-healing polyurethane elastomer with up-conversion fluorescence response that can be applied to optical devices , in order to replace the traditional non-self-healing optical device, solve the problem that the optical device is prone to microcracks during its molding, processing and use, thereby prolonging its service life and improving its use safety.

The specific technical solutions are as follows:

A preparation method of a fast self-healing polyurethane elastomer with up-conversion fluorescence response has such characteristics, comprising the steps of:

Step 1. Preparation of up-conversion fluorescent particles: dissolving rare earth chloride in a mixed solvent formed by mixing oleic acid and octadecene, then sequentially taking sodium hydroxide-methanol solution, ammonium fluoride-methanol solution and mixing rare earth The reaction is carried out in a mixed solvent of chloride, filtered after the reaction is completed, and the filtered precipitate is washed and dried to obtain the up-conversion fluorescent particles;

Step 2, preparing the composite material of up-conversion fluorescent particles and polyurethane prepolymer: dissolving diaminodiphenyldithiol in an organic solvent, then mixing it with polyurethane prepolymer and up-conversion fluorescent particles, and defoaming under vacuum , and finally the degassed mixture is cast in a mold for reaction, and a fast self-healing polyurethane elastomer with up-conversion fluorescence response is obtained after the reaction is completed.

The above preparation method also has the feature that the rare earth chloride is formed by mixing 80wt% yttrium chloride, 18wt% ytterbium chloride and 2wt% erbium chloride.

The above preparation method also has the feature that the rare earth chloride is formed by mixing 88wt% yttrium chloride, 10wt% erbium chloride and 2wt% thulium chloride.

The above preparation method also has the feature that the rare earth chloride is formed by mixing 80wt% yttrium chloride, 18wt% ytterbium chloride and 2wt% thulium chloride.

Above-mentioned preparation method also has such feature, in step 1 mixed solvent, the mixed volume ratio of oleic acid and octadecene is 1:2, and the add-on of rare earth chloride is 2mmol/ (every 45mL mixed solvent).

The above-mentioned preparation method also has such a feature that the mol ratio of rare earth chloride, sodium hydroxide and ammonium fluoride in step 1 is 2:5:8.

The above-mentioned preparation method also has the characteristics that in step 1, the reaction temperature is 300° C. and the reaction time is 1-2 h.

The above-mentioned preparation method also has the characteristics that in step 2, the mass ratio of diaminodiphenyldithiol, polyurethane prepolymer and up-conversion fluorescent particles is (0.28-0.35):(3.0-3.2):(1.125- 3.75).

The above-mentioned preparation method also has the characteristics that in the second step, the reaction temperature is 70-80° C., and the reaction time is 15-20 h.

In the present invention, disulfide bond groups are introduced into the polyurethane prepolymer to endow it with self-healing properties. Polyurethane (which can be prepared by the reaction of polyisocyanate and polyester or polyether polyol) reacts to synthesize self-healing polyurethane containing disulfide bond groups. damage effect.

The second aspect of the present invention is to provide a fast self-healing polyurethane elastomer with up-conversion fluorescence response prepared by the above preparation method.

In the present invention, the above-mentioned fast self-healing polyurethane elastomer with different colors and wide color gamut can self-heal into a new whole.

The beneficial effects of the above scheme are:

1) In the present invention, the upconversion fluorescent material is compounded with the self-healing polyurethane system, which can not only realize the healing/self-healing of the polymer material, but also introduce the external fluorescent light stimulus response, thereby obtaining a multi-fluorescence Responsive self-healing optics;

2) In the present invention, the self-healing polyurethane material based on multiple hydrogen bonds and disulfide bond cross-linking can also achieve infinite self-healing at room temperature while taking into account good mechanical properties.

Description of drawings

Fig. 1 is the topography diagram of self-healing polyurethane provided in the embodiment of the present invention under 980nm laser irradiation;

Fig. 2 is the color gamut diagram of the self-healing polyurethane provided in the embodiment of the present invention;

FIG. 3 is a process diagram of the healing test of the self-healing polyurethane provided in the embodiment of the present invention.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.

It should be noted that the embodiments of the present invention and the features of the embodiments may be combined with each other under the condition of no conflict.

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, but not as a limitation of the present invention.

Example 1

A fast self-healing polyurethane elastomer with up-conversion fluorescence response, the preparation method is as follows: take 2 mmol of rare earth chloride (Y ³⁺ : Yb ³⁺ :Er ³⁺ =80%:18%:2%) in It was dissolved in 15 mL of oleic acid and 30 mL of octadecene under magnetic stirring (500 rpm) at 160 °C. When it was lowered to room temperature, 5 mL of NaOH-methanol solution (NaOH content of 5 mmol) and 20 mL of NH ₄ F-methanol solution (NH 4 F-methanol solution) were rapidly added. ₄ F content was 8 mmol), and stirred and reacted at 50 °C for 30 minutes, then reacted at 300 °C for 1.5 hours, filtered, and successively used ethanol and cyclohexane to filter the precipitate at 8000 rpm for 5 minutes, and washed 3 times. Then, the up-conversion green fluorescent particles are obtained, and the above-mentioned up-conversion green fluorescent particles are taken and prepared to obtain a cyclohexane solution with a content of 7.5 mg/mL. 3) 3.1 g of diisocyanate-terminated polypropylene glycol, 150 μL of upconversion green fluorescent particles in cyclohexane, and 1.20 mL of diaminodiphenyldisulfide (0.28 g) in tetrahydrofuran were mixed with a planetary mixer for 5 minutes , form a uniform viscous mixture, defoaming the viscous mixture under vacuum for 15 minutes, then transfer to a square or round PTFE mold, and defoaming under vacuum for 30 minutes, and then continue in an oven at 75 ° C After the reaction is completed for 16 hours, a fast self-healing polyurethane elastomer with up-conversion fluorescence response can be obtained.

The fast self-healing polyurethane elastomer provided by the above example can only show green color under the excitation of 980nm laser (shown in Figure 1c), indicating that the fast self-healing polyurethane elastomer has an up-conversion green fluorescence response.

The mechanical properties test shows that the elongation at break of the fast self-healing polyurethane elastomer can reach 1037%, and the mechanical properties of the sample can be recovered by 97.8% at room temperature in 24 hours after complete cutting, showing good mechanical properties and self-healing. Fix performance.

Example 2

A fast self-healing polyurethane elastomer with up-conversion fluorescence response, the preparation method is as follows: take 2 mmol of rare earth chloride (Y ³⁺ :Er ³⁺ :Tm ³⁺ =88%:10%:2%) in It was dissolved in 15 mL of oleic acid and 30 mL of octadecene under magnetic stirring (500 rpm) at 160 °C. When it was lowered to room temperature, 5 mL of NaOH-methanol solution (NaOH content of 5 mmol) and 20 mL of NH ₄ F-methanol solution (NH 4 F-methanol solution) were rapidly added. ₄ F content was 8 mmol), and stirred and reacted at 50 ° C for 30 minutes, then reacted at 300 ° C for 1.5 hours, filtered, and successively used ethanol and cyclohexane to filter the precipitate at 8000 rpm for 5 minutes, and washed 3 times. Then, the up-conversion red fluorescent particles are obtained, and the above-mentioned up-conversion red fluorescent particles are taken and prepared to obtain a cyclohexane solution with a content of 25 mg/mL. 3) 3.1 g of diisocyanate-terminated polypropylene glycol, 150 μL of upconversion red fluorescent particles in cyclohexane, and 1.20 mL of diaminodiphenyldisulfide (0.28 g) in tetrahydrofuran were mixed with a planetary mixer for 5 minutes , form a uniform viscous mixture, defoaming the viscous mixture under vacuum for 15 minutes, then transfer to a square or round PTFE mold, and defoaming under vacuum for 30 minutes, and then continue in an oven at 75°C After the reaction is completed for 16 hours, a fast self-healing polyurethane elastomer with up-conversion fluorescence response can be obtained.

The fast self-healing polyurethane elastomer provided in the above example can only show red color under the excitation of 980nm laser (shown in Figure 1b), indicating that the fast self-healing polyurethane elastomer has an up-conversion red fluorescence response.

Example 3

A fast self-healing polyurethane elastomer with up-conversion fluorescence response, the preparation method is as follows: taking 2 mmol of rare earth chloride (Y ³⁺ : Yb ³⁺ : Tm ³⁺ =80%:18%:2%) in It was dissolved in 15 mL of oleic acid and 30 mL of octadecene under magnetic stirring (500 rpm) at 160 °C. When it was lowered to room temperature, 5 mL of NaOH-methanol solution (NaOH content of 5 mmol) and 20 mL of NH ₄ F-methanol solution (NH 4 F-methanol solution) were rapidly added. ₄ F content was 8 mmol), and stirred and reacted at 50 °C for 30 minutes, then reacted at 300 °C for 1.5 hours, filtered, and successively used ethanol and cyclohexane to filter the precipitate at 8000 rpm for 5 minutes, and washed 3 times. Then, the up-conversion blue fluorescent particles are obtained, and the above-mentioned up-conversion blue fluorescent particles are taken and prepared to obtain a cyclohexane solution with a content of 12.5 mg/mL. 3) 3.1 g of diisocyanate-terminated polypropylene glycol, 150 μL of a cyclohexane solution of up-conversion blue fluorescent particles, and 1.20 mL of a tetrahydrofuran solution of diaminodiphenyl disulfide (0.28 g) were mixed with a planetary mixer 5 minutes to form a homogeneous viscous mixture, defoamed the viscous mixture under vacuum for 15 minutes, then transferred to a square or round Teflon mold, defoamed under vacuum for 30 minutes, and then placed in an oven at 75°C The reaction is continued for 16 hours, and a fast self-healing polyurethane elastomer with up-conversion fluorescence response can be obtained after the reaction is completed.

The fast self-healing polyurethane elastomer provided in the above example can only show a blue color under the excitation of 980nm laser (as shown in Figure 1d), indicating that the fast self-healing polyurethane elastomer has an up-conversion blue fluorescence response. .

Comparative ratio

A rapid self-healing polyurethane elastomer, the preparation method of which is: mixing 3.1 g of diisocyanate-terminated polypropylene glycol and 1.35 mL of a tetrahydrofuran solution of diaminodiphenyl disulfide (0.28 g) with a planetary mixer for 5 minutes , form a uniform viscous mixture, then degas the above viscous mixture under vacuum for 15 minutes, then transfer to a square or round Teflon mold, and degas under vacuum for 30 minutes, in an oven at 75 ° C The reaction was continued for 16 hours to obtain a self-healing polyurethane elastomer.

The mechanical repair performance test shows that the elongation at break of the self-healing polyurethane elastomer can reach 1083%, and the mechanical properties of the completely cut sample can recover 98.5% in 24 hours at room temperature. Tests show that the self-healing polyurethane elastomer does not have an up-conversion fluorescence effect (shown in Figure 1a).

In the embodiment of the present invention, the polyurethane prepolymer is diisocyanate-terminated polypropylene glycol. The preparation method is as follows: take polypropylene glycol and add it to a 50 mL three-necked flask, stir in an oil bath at 70° C. for 5 minutes, and slowly add 3.2 mL dropwise. The isophorone diisocyanate was stirred for 10 minutes, and then 100 μL of the catalyst dibutyltin dilaurate was slowly added and stirred for 45 minutes to obtain a prepolymer diisocyanate-terminated polypropylene glycol.

The rapid self-healing polyurethane elastomer provided in the embodiment of the present invention has a wide color gamut. Specifically, as shown in FIG. 2 , the CIE of the rapid self-healing polyurethane elastomer provided in Examples 1-3 of the present invention The chromaticity coordinates are (0.6611, 0.3189), (0.2610, 0.7178), (0.1298, 0.1106), respectively.

In the present invention, the rapid self-healing polyurethane elastomers provided in Examples 1-3 are placed in layers and then self-healed at room temperature for a period of time to form a new complete whole. The above-mentioned complete whole is excited by a 980 nm laser. It still has an up-conversion fluorescence effect.

The above are only preferred embodiments of the present invention, and are not intended to limit the embodiments and protection scope of the present invention. For those skilled in the art, they should be aware of the equivalent replacement and Solutions obtained by obvious changes shall all be included in the protection scope of the present invention.

Claims (10)

1. A preparation method of a rapid self-healing polyurethane elastomer with up-conversion fluorescent response is characterized by comprising the following steps:

step one, preparing up-conversion fluorescent particles: dissolving rare earth chloride in a mixed solvent formed by mixing oleic acid and octadecene, sequentially taking a sodium hydroxide-methanol solution and an ammonium fluoride-methanol solution, mixing the sodium hydroxide-methanol solution and the ammonium fluoride-methanol solution into the mixed solvent in which the rare earth chloride is dissolved, reacting, filtering after the reaction is finished, washing and drying a filtered precipitate to obtain up-conversion fluorescent particles;

step two, preparing the composite material of the up-conversion fluorescent particles and the polyurethane prepolymer: dissolving diamino-benzenedithiol in an organic solvent, mixing the diamino-benzenedithiol with a polyurethane prepolymer and up-conversion fluorescent particles, defoaming in vacuum, casting the defoamed mixture in a mold for reaction, and obtaining the quick self-healing polyurethane elastomer with up-conversion fluorescent response after the reaction is finished.

2. The method for preparing the rare earth metal chloride as claimed in claim 1, wherein the rare earth chloride is formed by mixing 80 wt% of yttrium chloride, 18 wt% of ytterbium chloride and 2 wt% of erbium chloride.

3. The method for preparing the alloy according to claim 1, wherein the rare earth chloride is formed by mixing 88 wt% of yttrium chloride, 10 wt% of erbium chloride and 2 wt% of thulium chloride.

4. The method for preparing according to claim 1, wherein the rare earth chloride is formed by mixing 80 wt% yttrium chloride, 18 wt% ytterbium chloride and 2 wt% thulium chloride.

5. The method according to any one of claims 2 to 4, wherein the mixed volume ratio of oleic acid and octadecene in the mixed solvent of step one is 1:2, and the amount of the rare earth chloride added is 2 mmol/(per 45mL of the mixed solvent).

6. The method of claim 5, wherein the molar ratio of the rare earth chloride, the sodium hydroxide and the ammonium fluoride in the first step is 2:5: 8.

7. The method according to claim 1, wherein the reaction temperature in the first step is 300 ℃ and the reaction time is 1 to 2 hours.

8. The method of claim 1, wherein the mass ratio of the diaminobenzenedithiol, the polyurethane prepolymer, and the upconversion fluorescent particles in the second step is (0.28-0.35): (3.0-3.2): (1.125-3.75).

9. The preparation method according to claim 1, wherein the reaction temperature in the second step is 70-80 ℃ and the reaction time is 15-20 h.

10. A fast self-healing polyurethane elastomer with up-conversion fluorescent response, which is prepared according to the preparation method of any one of claims 1 to 9.