A polyurethane sponge with mosquito-repellent function and its preparation method

Abstract

This invention relates to a polyurethane sponge with mosquito-repellent function and its preparation method. The preparation method involves mixing an inflatable polyether polyol, a DEET-modified polyether polyol, a polyether glycol, and ethyl butylacetaminopropionate to obtain a first mixture; mixing a catalyst, an organosilicon surfactant, and a foaming agent to obtain a second mixture; and stirring and mixing the first mixture, the second mixture, and a modified isocyanate, followed by curing. In this preparation method, ethyl butylacetaminopropionate-modified polyether polyol is used as a raw material in the polyurethane reaction, resulting in a graft copolymer that remains permanently within the polyurethane sponge. This creates a barrier within the polyurethane sponge, effectively blocking the emission of odors, paralyzing the olfactory system of mosquitoes, and interfering with their odor perception, thus achieving a mosquito-repellent effect. Furthermore, the tensile strength, elongation, and tear strength all meet relevant standards, demonstrating excellent overall performance.

Description

Technical Field

[0001] This invention belongs to the field of functional polyurethane, specifically relating to a polyurethane sponge with mosquito-repellent function and its preparation method. Background Technology

[0002] Summer's heat and humidity make it the peak season for mosquitoes and other blood-sucking insects. Various types of mosquitoes and other insects can cause skin itching, inflammation, and other symptoms through their bites and bloodsucking.

[0003] Patent CN217447204U discloses a mosquito-repellent mattress, which includes a mattress body, a support device, and a mosquito net. This invention allows the mosquito net to be stored within the mattress body or removed from it for mosquito repellency. It achieves its mosquito-repellent effect through this external device. Patent CN217309775U uses mosquito-repellent sachets and fillings to repel mosquitoes, preventing them from making it difficult for the user to fall asleep. Both of these patents achieve their mosquito-repellent effect by adding external mosquito-repellent devices, but they do not fundamentally solve the problem and their effectiveness is time-limited.

[0004] Patent CN111117388A discloses an environmentally friendly mosquito-repellent coating and its preparation method. This invention places mosquito-repellent ingredients inside microspheres and releases them under suitable external conditions to achieve a mosquito-repellent effect. However, inevitably, over time, the amount of mosquito-repellent ingredients decreases, and the mosquito-repellent effect is not long-lasting.

[0005] Therefore, based on this, the technical solution of the present invention is proposed. Summary of the Invention

[0006] To address the problems existing in the prior art, the present invention provides a method for preparing a polyurethane sponge with mosquito-repellent function, comprising the following steps:

[0007] (1) Mix gas-expanding polyether polyol, IR353-modified polyether polyol, polyether diol and ethyl butyl acetaminopropionate to obtain the first mixture;

[0008] (2) The catalyst, organosilicon surfactant and foaming agent are mixed to obtain a second mixture;

[0009] (3) The first mixture, the second mixture and the modified isocyanate are stirred and mixed, and the polyurethane sponge is obtained after aging.

[0010] Preferably, the raw materials of the present invention are: 40-60 parts by weight of gas-expanding polyether polyol, 20-60 parts by weight of DEET-modified polyether polyol, 20-30 parts by weight of polyether diol, 0.3-4.5 parts by weight of ethyl butyl acetaminopropionate, 0.05-3 parts by weight of catalyst, 0.05-5 parts by weight of organosilicon surfactant, 1-3 parts by weight of foaming agent, and 40-70 parts by weight of modified isocyanate.

[0011] Preferably, in step (1), the gas-expanding polyether polyol is polyoxypropylene triol with a molecular weight of 3000~5000 (more preferably, a molecular weight of 3500~4000), a hydroxyl value of 25~550mg KOH / g, a colorless or light yellow transparent oily liquid, insoluble in water, and with high activity.

[0012] Preferably, in step (1), the DEET-modified polyether polyol is obtained by directly alcoholystolysis or transesterification of ethyl butylacetaminopropionate to obtain ester polyols with different hydroxyl values, functionalities, and relative molecular weights. Ethyl butylacetaminopropionate is a compound containing acetamino and ester groups. By adding polyether polyols of different molecular weights, such as polypropylene glycol or vegetable oil polyols, and using concentrated sulfuric acid as a catalyst, a transesterification reaction is carried out at 60°C, while simultaneously undergoing dehydration. The product is then deacidified, separated, and dried to finally obtain the DEET-modified polyether polyol. The molecular weight of the DEET-modified polyether polyol is 800~6000, preferably 2000~4000; the functionality is 1~5, and the effective functionality is 2~4. The obtained DEET-modified polyether polyol is detected using an infrared spectrometer, and the results are as follows: Figure 1 As shown, in the wavenumber range of 1350~1000cm -1 A CN bond stretching vibration absorption band appears at 1648 cm⁻¹. -1 A stretching vibration peak of the carbonyl group on the amide group appears at 1734 cm⁻¹. -1 An absorption peak appears at 2960 cm⁻¹ on the carbonyl group of the ethyl propionate group. -1 and 2933cm -1 The presence of two stretching vibration peaks of CH bonds indicates successful preparation.

[0013] Preferably, in step (1), the polyether glycol is polypropylene glycol (PPG-2000), with a molecular weight of 1000~2000, a hydroxyl value of 56~112 mg KOH / g, a clear colorless or light yellow transparent oily liquid, soluble in organic solvents such as ethanol, and can react with diisocyanate to generate linear polyurethane.

[0014] In step (2), ethyl butyl acetylaminopropionate is an insect repellent used to paralyze the olfactory system of mosquitoes and interfere with their olfactory perception, thereby achieving the effect of repelling mosquitoes.

[0015] Preferably, in step (2), the catalyst is triethylenediamine and bis(dimethylaminoethyl) ether. Triethylenediamine mainly acts as a gel catalyst for polyurethane, and has strong selectivity for the catalytic effect of polyurethane and hydroxyl groups (urethane formation reaction, gel reaction); bis(dimethylaminoethyl) ether is used to control the gas generation reaction in 80% and the gelation in 20%, thereby controlling the foaming rise and gelation time, so as to reduce the foam density.

[0016] Preferably, in step (2), the organosilicon surfactant is a polyether-modified organosilicon surfactant, such as Momentive L-580, whose main structure is a polysiloxane-oxidized olefin block or graft copolymer, which can increase the miscibility of each component and play the role of emulsifying foam materials, stabilizing foam and regulating cell structure.

[0017] Preferably, in step (2), the foaming agent is a chemical foaming agent or a physical foaming agent. The chemical foaming agent is water, and the physical foaming agent is dichloromethane, which vaporizes by absorbing heat.

[0018] The modified isocyanate is polyether-modified diphenylmethane diisocyanate, whose molecular structure contains two benzene rings, which enables the prepared polyurethane foam to have better mechanical properties. Benzene is nitrated with nitric acid to produce nitrobenzene, which is then hydrogenated to produce aniline. Aniline undergoes a condensation reaction with formaldehyde to obtain diaminodiphenylmethane, which is then subjected to a phosgenation reaction and purified to obtain diphenylmethane diisocyanate.

[0019] Preferably, in step (3), the stirring speed is 2000~3000r / min and the stirring time is 6~10s; the maturation is carried out at room temperature for 24~72h.

[0020] Based on the same technical concept, another aspect of the present invention is to provide a polyurethane sponge with mosquito-repellent function obtained by the above preparation method.

[0021] The polyurethane sponge with mosquito-repellent function described in this invention has an open-cell structure, which has good elasticity and breathability. It can be mainly used in mattresses, sofas, pillows, car seats, etc., and plays an important role in people's lives and work.

[0022] The beneficial effects of this invention are as follows:

[0023] The preparation method described in this invention uses ethyl butyl acetylaminopropionate modified polyether polyol as a raw material to participate in the polyurethane reaction, generating a graft copolymer in the molecular structure that remains permanently in the polyurethane sponge. A thin film is formed on the surface of the sponge structure, thereby isolating the emission of odors and directly acting on the tactile organs and chemoreceptors of mosquitoes, paralyzing the olfactory system of mosquitoes, and interfering with the mosquitoes' perception of odors, so as to achieve the effect of repelling mosquitoes.

[0024] The polyurethane foam with mosquito-repellent function obtained by this invention has a tensile strength ≥50kPa (GB / T 6344-2008), an elongation ≥110% (GB / T 6344-2008), a tear strength ≥3.0N / cm (GB / T 10808-2006), and a mosquito-repellent rating of B (GB / T 30126-2013), all of which fully meet the relevant standards and demonstrate excellent overall performance. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is the infrared spectrum of the ester-modified polyether polyol described in this invention. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be described in detail below. Obviously, the described embodiments are merely some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other implementation methods obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0028] Example 1

[0029] This embodiment provides a method for preparing a polyurethane sponge with mosquito-repellent function, including the following steps:

[0030] (1) Polyoxypropylene triol, DEET-modified polyether polyol, polypropylene glycol (PPG-2000) and ethyl butyl acetaminophen are mixed to obtain the first mixture;

[0031] (2) Mix bis(dimethylaminoethyl) ether, triethylenediamine, zinc stannin, water and Momentive L-580 to obtain a first mixture;

[0032] (3) The first mixture, the second mixture and the modified isocyanate (8122) are stirred and mixed at 2000 r / min for 10s. After the mixture is completed, it is poured into a foaming mold or a polyurethane foaming machine is used. After 72h of curing, the polyurethane sponge is obtained.

[0033] The raw material information used in this embodiment is shown in Table 1.

[0034] Table 1 Raw material information for the examples

[0035]

[0036] Example 2, Example 3

[0037] The operation process of Examples 2 and 3 is the same as that of Example 1, but the raw material parameters are different, as shown in Table 2.

[0038] Table 2 Raw material and operation information for Examples 2 and 3

[0039]

[0040] Comparative Example 1

[0041] The difference between this comparative example and the examples is that no DEET-modified polyether polyol and ethyl butyl acetaminopropionate are added; all other operations are the same as in the examples.

[0042] Comparative Example 2

[0043] The difference between this comparative example and the examples is that ethyl butylacetylaminopropionate is not added; all other operations are the same as in the examples.

[0044] The raw material information used in Comparative Example 1 and Comparative Example 2 is shown in Table 3.

[0045] Table 3 Raw material information for Comparative Examples 1-2

[0046]

[0047] The products obtained from the examples and comparative examples 1-2 were tested, and the results are shown in Table 4.

[0048] Table 4 Test Results

[0049]

[0050] Based on the reaction mechanism of this invention and the data analysis in Tables 3 and 4, it can be concluded that:

[0051] The mosquito-repellent polyurethane sponge of this invention uses ethyl butyl acetaminopropionate and its modified polyether polyol. The ethyl ester itself participates in the polyurethane reaction, generating a graft copolymer on the molecular structure of the polyurethane sponge. This forms a thin film on the surface of the sponge structure, thereby blocking the emission of object odors and acting directly on the mosquito's tactile organs and chemoreceptors, paralyzing the mosquito's olfactory system, and interfering with the mosquito's perception of odors, thus achieving the effect of repelling mosquitoes.

[0052] Therefore, Comparative Example 1, which did not contain ethyl butyl acetaminopropionate and DEET-modified polyether polyol, did not have a mosquito-repellent effect; Comparative Example 2, which did not contain ethyl butyl acetaminopropionate, had a moderate mosquito-repellent effect; Example 1 had the best mosquito-repellent effect and a good repellent effect.

[0053] In terms of mechanical properties, since no DEET-modified polyether polyol was added, the tensile strength, elongation, and tear strength of Comparative Example 1 were all lower than those of Example 1 and Comparative Example 2. DEET-modified polyether polyol has a relatively increased molecular weight, more branches, increased reactivity, and stronger cross-linking compared to the original polyether polyol, thereby optimizing the mechanical properties of the polyurethane product.

[0054] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for preparing a polyurethane sponge with mosquito-repellent function, characterized in that, The preparation method includes the following steps: (1) Mix gas-expanding polyether polyol, DEET-modified polyether polyol, polyether diol and ethyl butyl acetaminopropionate to obtain a first mixture; wherein: The gas-expanding polyether polyol is polyoxypropylene triol with a molecular weight of 3000~5000 and a hydroxyl value of 25~550 mg KOH / g; (2) The catalyst, organosilicon surfactant and foaming agent are mixed to obtain a second mixture; (3) The first mixture, the second mixture and the modified isocyanate are stirred and mixed, and after aging, the polyurethane sponge is obtained; Ethyl butylacetylaminopropionate is a compound containing acetylamino and ester groups. By adding polyether polyols of different molecular weights of polyoxypropylene triol, using concentrated sulfuric acid as a catalyst, a transesterification reaction is carried out at 60°C, while simultaneously undergoing dehydration treatment. The product is then deacidified, separated, and dried to finally obtain the DEET-modified polyether polyol.

2. The preparation method according to claim 1, characterized in that, The weight ratio of gas-expanding polyether polyol, DEET-modified polyether polyol, polyether diol, ethyl butyl acetylaminopropionate, catalyst, silicone surfactant, foaming agent and modified isocyanate is 40~60:20~60:20~30:0.3~4.5:0.05~3:0.05~5:1~3:40~70.

3. The preparation method according to claim 1, characterized in that, In step (1), the polyether glycol is polypropylene glycol with a molecular weight of 1000~2000 and a hydroxyl value of 56~112 mg KOH / g.

4. The preparation method according to claim 1, characterized in that, In step (2), the catalyst is triethylenediamine and bis(dimethylaminoethyl) ether.

5. The preparation method according to claim 1, characterized in that, In step (2), the foaming agent is either water or dichloromethane.

6. The preparation method according to claim 1, characterized in that, In step (3), the stirring speed is 2000~3000 r / min and the stirring time is 6~10 s.

7. The preparation method according to claim 1, characterized in that, In step (3), the ripening is carried out at room temperature for 24 to 72 hours.

8. The polyurethane sponge with mosquito-repellent function obtained by the preparation method according to any one of claims 1 to 7.

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