Hydrogel dressing with high temperature reminding and recycling function and preparation method thereof

Abstract

The application belongs to the field of functional polymer hydrogel materials, and particularly relates to a hydrogel dressing with high-temperature reminding and recycling functions and a preparation method thereof, which comprises polycaprolactone, polyethylene glycol, HDI trimer, peroxide, temperature-sensitive color-changing powder and inorganic additive; the mass ratio of the polycaprolactone to the polyethylene glycol is 1:0.05-0.5; the mass ratio of the polycaprolactone to the peroxide is 1:0.01-0.08; the mass ratio of the polycaprolactone to the inorganic additive is 1:0.01-0.07; the mass ratio of the polycaprolactone to the temperature-sensitive color-changing powder is 1:0.02-0.06; and the mass ratio of the polycaprolactone to the HDI trimer is 1:0.02-0.10. The material has ideal moisturizing property, high mechanical strength, toughness, tear resistance and insulation.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of functional polymer hydrogel materials, and particularly relates to a hydrogel dressing with high-temperature reminding and recycling functions and a preparation method thereof. BACKGROUND

[0002] Polymer hydrogels have a space network structure, and can accommodate small molecular substances such as water and pharmaceutical active substances in the structure voids. When applied or covered on the skin, they can create a humid environment and release drug molecules. However, most of the current hydrogels are soft in texture, and those with high mechanical strength and toughness have relatively complex preparation conditions, which limits their further practical application. Therefore, using a simple method and commercial raw materials to prepare hydrogels that are both strong and tough will have wide application prospects. SUMMARY

[0003] The present application aims to overcome the deficiencies of the prior art and provide a hydrogel dressing with high-temperature reminding and recycling functions, which has ideal moisturizing properties, high mechanical strength, toughness, tear resistance and insulation performance, and a preparation method thereof.

[0004] To solve the above technical problems, the present application is implemented as follows:

[0005] The hydrogel dressing with high-temperature reminding and recycling functions comprises polycaprolactone, polyethylene glycol, HDI trimer, peroxide, temperature-sensitive color-changing powder and inorganic additive; the mass ratio of the polycaprolactone to the polyethylene glycol is 1:0.05-0.5; the mass ratio of the polycaprolactone to the peroxide is 1:0.01-0.08; the mass ratio of the polycaprolactone to the inorganic additive is 1:0.01-0.07; the mass ratio of the polycaprolactone to the temperature-sensitive color-changing powder is 1:0.02-0.06; and the mass ratio of the polycaprolactone to the HDI trimer is 1:0.02-0.10.

[0006] Further, the polycaprolactone has a molecular weight of 80,000; and the polyethylene glycol has a molecular weight of 20,000.

[0007] Further, the peroxide is benzoyl peroxide.

[0008] Further, the inorganic additive is white carbon black, calcium carbonate, talc or silicon dioxide.

[0009] Further, the temperature-sensitive color-changing powder is a temperature-sensitive color-changing powder with a color-changing property at 45℃.

[0010] The preparation method of the above-mentioned hydrogel dressing with high-temperature reminding and recycling functions comprises the following steps: (1) heating polycaprolactone and polyethylene glycol to melt;

[0011] (2) dissolving the peroxide in an organic solvent;

[0012] (3) mixing the solution obtained in step (2), the thermochromic powder, the inorganic additive and the HDI trimer with the product obtained in step (1);

[0013] (4) placing the mixture obtained in step (3) into a mold of a flat vulcanizing machine, adjusting the temperature of the upper and lower plates of the flat vulcanizing machine, closing the flat plate and pressurizing, releasing the pressure after heating, taking out the mold, and demolding after cooling, to obtain a raw dressing sheet with a thickness of 0.2 mm;

[0014] (5) immersing the raw dressing sheet obtained in step (4) in water overnight, taking it out and wiping the surface dry, to obtain a hydrogel dressing with high-temperature reminding and recycling functions.

[0015] Further, the organic solvent is N,N-dimethylformamide.

[0016] Further, in step (1), the polycaprolactone and the polyethylene glycol are heated to melt at 65℃.

[0017] Further, in step (3), the solution obtained in step (2), the thermochromic powder, the inorganic additive and the HDI trimer are mixed with the product obtained in step (1), and the temperature is kept at 69℃.

[0018] Further, in step (4), the temperature of the upper and lower plates of the flat vulcanizing machine is adjusted to 140℃, the flat plate is closed and pressurized to 5 MPa, the pressure is released after heating for 10 minutes, the mold is taken out, and demolding is performed after cooling, to obtain a raw dressing sheet with a thickness of 0.2 mm.

[0019] The present application adopts high molecular weight polycaprolactone, polyethylene glycol, HDI trimer (hexamethylene diisocyanate), peroxide, thermochromic powder and inorganic additive to compose a gel dressing formula. This formula can be directly hot-pressed into a 0.2 mm thick sheet. After cooling, the material is immersed in water, and the prepared hydrogel is both strong (14.07 MPa) and tough (4824.75 MJ / m³) and has high tear resistance and insulation. The hydrogel has a porous structure inside, which can keep the skin moist. It acts directly or indirectly on the skin, and after covering the self-heating patch, it can promote the dilation of skin pores, thereby accelerating the absorption of functional molecules by the skin. At the same time, when the heat approaches the tolerance temperature of human skin (about 45 degrees), the hydrogel will change color, having a high-temperature reminding function. In addition, the dressing can recover its original shape by immersing in hot water after deformation, having a recycling function. This hydrogel dressing has a wide application prospect in the fields of cosmetics, health care products and medical treatment. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1Stress-strain curve of the hydrogel dressing with high temperature reminding and recycling functions of the present application;

[0021] Figure 2 Schematic diagram of the hydrogel of the present application covering the self-heating patch on the skin;

[0022] Figure 3 Color change of the hydrogel dressing of the present application (room temperature, 40 degrees and 45 degrees);

[0023] Figure 4 Deformation recovery process of the hydrogel dressing of the present application;

[0024] Figure 5 Right-angle tearing curve of the hydrogel dressing of the present application. DETAILED DESCRIPTION

[0025] In order to enable those skilled in the art to better understand the technical solutions of the present application, the present application will be further described below in combination with specific embodiments. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. These embodiments should be understood as merely illustrating the present application, but not limiting the protection scope of the present application. After reading the content recorded in the present application, based on the technical solutions and embodiments of the present application, all other embodiments obtained by various modifications or modifications of the present application also fall within the protection scope of the present application. The experimental methods in the following embodiments are conventional methods, unless otherwise specified.

[0026] The preparation method of the hydrogel dressing with high temperature reminding and recycling functions comprises:

[0027] First, a certain amount of polycaprolactone (molecular weight 80,000) and polyethylene glycol (molecular weight 20,000) are weighed into a beaker and heated to complete melting at 65°C. Then, a certain amount of benzoyl peroxide (BPO) is weighed into another beaker and dissolved with a small amount of N,N-dimethylformamide (DMF). Then, the DMF solution containing BPO, a small amount of temperature-sensitive color-changing powder, white carbon black and HDI trimer are mixed uniformly with the molten polycaprolactone / polyethylene glycol (the temperature is kept at 69°C). Then, the mixture in the beaker is quickly taken out and placed in the mold of a flat vulcanizing machine. The temperature of the upper and lower plates of the flat vulcanizing machine is adjusted to 140°C, the flat plate is closed and pressurized to 5MPa, and after heating for 10 minutes, the pressure is released. Finally, the mold is taken out, and after it is completely cooled, it is demolded, and the original dressing sheet with a thickness of 0.2mm is obtained.

[0028] Second, the original dressing sheet is directly immersed in water overnight, and then taken out and the surface is wiped dry, so that the hydrogel dressing with high temperature reminding and recycling functions can be obtained. This dressing can be reused. If it is deformed, it only needs to be immersed in hot water at 65°C, and after it returns to the original shape, it can be used again.

[0029] Third, the hydrogel can be directly attached to the skin and covered with a self-heating patch. As the temperature rises, it can promote the dilation of skin pores. At the same time, when the temperature approaches the tolerance limit of human skin (about 45 degrees), the hydrogel will change color (from purple to light blue), thus having the function of high temperature reminding. Example

[0030] The preparation method of the hydrogel dressing with high temperature reminding and recycling functions includes:

[0031] (1) 25 grams of polycaprolactone (molecular weight 80,000) and 5 grams of polyethylene glycol (molecular weight 20,000) are weighed into a beaker and heated to complete melting at 65°C. In addition, 1.25 grams of benzoyl peroxide (BPO) is weighed into another beaker and dissolved with a small amount of N,N-dimethylformamide (DMF). Then, the DMF solution containing BPO, 0.75 grams of temperature-sensitive color-changing powder, 0.85 grams of white carbon black, and 0.75 grams of HDI trimer are mixed uniformly with the molten polycaprolactone / polyethylene glycol (the temperature is kept at 69°C). The mixture in the beaker is quickly taken out and placed in the mold of a flat vulcanizing machine. The temperature of the upper and lower plates of the flat vulcanizing machine is adjusted to 140°C, the flat plate is closed and pressurized to 5 MPa, and after heating for 10 minutes, the pressure is released. The mold is taken out, and after it is completely cooled, it is demolded, and the original dressing sheet with a thickness of 0.2 millimeters is obtained.

[0032] (2) The original dressing sheet is directly immersed in water overnight, and then taken out and the surface is wiped dry, so that the hydrogel dressing with high temperature reminding and recycling functions can be obtained. Figure 4 ).

[0033] (3) The hydrogel can be directly or indirectly attached to the skin. After covering the self-heating patch, as the temperature rises, it can promote the dilation of skin pores. Figure 2 ). At the same time, when the temperature approaches the tolerance limit of human skin (about 45 degrees), the hydrogel will change color (from purple to light blue), thus having the function of high temperature reminding. Figure 3 ).

[0034] (4) Under room temperature, the tensile mechanical property of the hydrogel was tested by using the universal testing machine DR-506A. The tensile test was carried out according to the standard GB / T 528-2009. The sample was cut by using the international III type cutter. That is, the sample of the hydrogel had a gauge length of 16 mm, a width of 4 mm and a thickness of 0.22 mm. The sample was stretched in the axial direction at a stretching speed of 10 mm / min until the sample was broken. The breaking elongation was 459.46%, the elastic modulus was 34.60 MPa, the tensile strength was 14.07 MPa, the maximum tension was 14.07 N, and the toughness was 4824.75 MJ / m 3 Figure 1

[0035] (5) Under room temperature, the right-angle tearing test of the hydrogel was carried out by using the universal testing machine DR-506A, and the tearing strength test was carried out according to the standard GB / T 529-2008. The maximum force Fm required for tearing the sample was 108.81 N, and the tearing strength Ts was 60.15 KN / m Figure 5

[0036] (6) The volume resistance of the sample was determined by using the high insulation resistance tester ZC-36, and then the volume resistivity was calculated. The resistance test was carried out according to the standard GB / T 1410-2006. The volume resistivity of the sample was 8.7 x 10 11 Ω·cm, which met the standard of the volume resistivity of 10 11 Ω·cm of the insulation material, and belonged to a good insulation material.

[0037] The above-described embodiments are only preferred embodiments of the present application and are not used to limit the present application. It should be pointed out that the present application can have various changes and variations for those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.​​​

Claims

1. A method for preparing a hydrogel dressing with high temperature reminding and recycling functions, characterized in that, Comprising the following steps: (1) Take 25 grams of polycaprolactone with a molecular weight of 80,000 and 5 grams of polyethylene glycol with a molecular weight of 20,000 into a beaker, heat to complete melting at 65℃; (2) Take 1.25 grams of benzoyl peroxide into another beaker and dissolve with a small amount of N,N-dimethylformamide; (3) Mix the N,N-dimethylformamide solution containing benzoyl peroxide obtained in step (2), 0.75 grams of thermosensitive color-changing powder, 0.85 grams of white carbon black and 0.75 grams of HDI trimer with the molten polycaprolactone / polyethylene glycol obtained in step (1) uniformly, and keep the temperature at 69℃; (4) Take out the mixture in the beaker quickly and put it into the mold of a flat vulcanizing machine, adjust the temperature of the upper and lower plates of the flat vulcanizing machine to 140℃, close the flat and pressurize to 5MPa, heat for 10 minutes, then release the pressure, take out the mold, wait for it to cool completely, then demold, and you get the original dressing sheet with a thickness of 0.2mm; (5) Soak the original dressing sheet in water overnight, then take it out and wipe off the surface, and you get a hydrogel dressing with high temperature reminding and recycling functions; when the temperature approaches the tolerance limit of human skin, 45 degrees, the hydrogel will change color.

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