Insect screen

Abstract

The present application relates to the technical field of gardening insect prevention, and particularly relates to an insect prevention net, which is composed of a plurality of warp yarns and a plurality of weft yarns; the edge of the insect prevention net contains an edge sealing part, which is wrapped around the end of the weft yarn; a plurality of indentations are arranged on the edge sealing part; the warp yarns and the weft yarns are obtained by mixing 0.5-4 parts of an ultraviolet-resistant additive and 90-130 parts of modified PET and then melt spinning. The insect prevention net can solve the problem of burrs after cutting, make the edge of the insect prevention net more flat, improve the installation safety and the use comfort, and meanwhile, the insect prevention net has good air permeability, light transmittance and flame retardant property, and is more stable in structure shape during use.

Description

Technical Field

[0001] This invention relates to the field of horticultural pest control technology, and in particular to an insect-proof net. Background Technology

[0002] Insect nets, as physical protective devices used to isolate insects from target spaces, have seen their technological development revolve around optimizing material performance, innovating structural design, and integrating functions. Early insect nets were mostly woven from natural fibers or metal wires, achieving insect control through physical barriers. However, these products suffered from significant drawbacks such as susceptibility to corrosion, poor air permeability, and weak aging resistance. With advancements in polymer science, synthetic fibers, represented by polyethylene, polypropylene, and polyethylene terephthalate, have gradually become the mainstream substrate. Optimizing the weaving process allows for precise control of mesh size, effectively intercepting small insects while ensuring ventilation and light transmission.

[0003] In the agricultural field, the application of insect-proof nets has expanded from single greenhouse protection to a three-dimensional protection system for open-field planting. Traditional planar insect-proof nets have problems such as limited coverage and insufficient wind resistance. Modern technology, by introducing a three-dimensional weaving structure and flexible support system, enables the protective nets to adapt to complex terrain and form a dynamic protective barrier. Although insect-proof net technology has made significant progress, existing products still face several challenges, and research on insect-proof nets is ongoing. For example, CN109023571B discloses "a composite fiber and its application in rice insect-proof nets," which is composed of fiber matrix material, chitosan microparticles, copper stearate, and europium ions. It can prevent rice planthoppers and increase the intensity of the red spectrum, thereby increasing rice yield.

[0004] However, most insect nets currently have an accordion-style structure. To support the stability of the accordion-style structure, the warp threads are often woven from two wires or two layers of mesh are stacked to make the insect net. This method greatly reduces the ventilation performance, and due to the increase in thickness, the light transmittance of the mesh decreases, which is not conducive to sunlight entering the house and thus affects the growth of crops.

[0005] Therefore, it is urgent to develop an insect-proof net that is structurally stable and has high light transmittance when unfolded. Summary of the Invention

[0006] The main objective of this invention is to provide an insect-proof net that, when made into an accordion-style insect-proof net, has a more stable unfolded structure, higher light transmittance, excellent flame retardant effect, and smooth edges on individual insect-proof net panels that are easy to handle and do not scratch the hands.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] The present invention provides an insect-proof net, which is composed of multiple warp yarns and multiple weft yarns; the edge of the insect-proof net has a sealing edge that covers the end of the weft yarn; multiple indentations are provided on the sealing edge; by weight, the warp yarn and the weft yarn are made by mixing and remelting 0.5 to 4 parts of UV-resistant additive and 90 to 130 parts of modified PET.

[0009] In some embodiments, the ends of each of the weft yarns are fused together.

[0010] In some embodiments, the sealing edge is a film or webbing.

[0011] In some embodiments, the method for preparing the modified PET includes the following steps: under an inert protective gas atmosphere, terephthalic acid, ethylene glycol, functional polyol and catalyst are mixed, pressurized to 0.01-0.03 MPa, heated to 220-250°C, and reacted for 2-4 hours. Then, a vacuum is drawn to a pressure of 2300-2500 Pa, and the reaction continues for 1.2-1.8 hours. Subsequently, the temperature is raised to 260-280°C, the pressure is maintained at 50-100 Pa, and the mixture is stirred at a constant temperature for 1.5-2 hours to obtain the modified PET.

[0012] In some embodiments, the mass ratio of terephthalic acid, ethylene glycol, and functional polyol is 1:(1-1.3):(0.2-0.5).

[0013] In some embodiments, the functional polyol comprises the structure shown in Formula I:

[0014]

[0015] In some embodiments, the method for preparing the functional polyol includes the following steps:

[0016] A1. Under an inert protective gas atmosphere, the first batch of cyanuric chloride was dissolved in acetonitrile, cooled to -5 to 0°C in an ice bath, and resorcinol, aniline, and an acid-binding agent were added. After the addition was complete, the temperature was raised to room temperature and the reaction was carried out for 5 to 7 hours. Then, the second batch of cyanuric chloride was added and the mixture was stirred for another 5 to 7 hours. After the reaction was completed, the mixture was filtered, concentrated under reduced pressure, and subjected to column chromatography to obtain the compound represented by Formula II.

[0017]

[0018] A2. Under an inert protective gas atmosphere, the compound represented by formula II in step A1 is mixed with toluene, cooled to -5 to 0°C in an ice bath, ethanolamine and an acid-binding agent are added, and the mixture is stirred at a constant temperature for 6 to 7 hours. After the reaction is completed, the mixture is filtered, concentrated under reduced pressure, and obtained by column chromatography.

[0019] The insect-proof net of this application is composed of monofilaments in both the warp and weft, which improves the ventilation performance of the insect-proof net. However, the applicant's research found that when the monofilament insect-proof net is made into a folded insect-proof net, the monofilaments are not rigid enough to maintain the unfolded structure of the insect-proof net, resulting in sagging that affects its use and appearance. In addition, conventional PET has poor flame retardant properties, which poses a safety hazard of becoming a fuse during both production and use.

[0020] This application presents a self-made modified PET that avoids the migration and precipitation phenomena easily caused by adding other additives, while also improving the structural stability, flame retardant properties, and light transmittance of the insect-proof net. The reasons for this are likely as follows: First, the modified PET structure contains a small amount of hydroxyl groups, which can inhibit PET crystallization through self-hydrogen bond cross-linking, disrupting the regularity of PET, reducing light scattering, and thus improving the light transmittance of the modified PET. Second, the modified PET structure contains a large amount of triazine and phenyl structures, which synergistically form a π-π stacking effect, increasing the rigidity of the modified PET and thus improving the structural stability of the insect-proof net. Third, the modified PET structure contains a large amount of nitrogen, which, when burned, decomposes to produce nitrogen-containing gas that can capture active free radicals, thereby reducing the burning intensity and improving the flame retardant properties of the insect-proof net.

[0021] In some embodiments, in step A1, the molar ratio of the first batch of cyanuric chloride, aniline and resorcinol is 1:(1-1.2):(2.2-2.5).

[0022] In some embodiments, in step A1, the molar ratio of the second batch of cyanuric chloride to resorcinol is (1-1.3):1.

[0023] In some embodiments, in step A2, the molar ratio of the compound represented by Formula II to ethanolamine is 1:(4 to 4.5).

[0024] In some embodiments, the acid-binding agent is any one of triethylamine, sodium carbonate, potassium carbonate, sodium bicarbonate, and potassium bicarbonate.

[0025] In some embodiments, the width of the insect-proof net is 7 to 20 cm.

[0026] In some embodiments, the warp and weft yarns are monofilaments.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] (1) The insect net of the present invention is woven with a monofilament structure, and the edge of the insect net is sealed and bound to the weft yarn end and fixed, which solves the problem of edge burrs after traditional cutting, making the edge of the insect net smoother, improving installation safety and usage comfort. At the same time, the monofilament woven insect net has better air permeability.

[0029] (2) The insect-proof net of the present invention is made by melt spinning a mixture of modified PET and UV-resistant additives. The modified PET structure contains a small amount of hydroxyl, triazine and phenyl structures. The hydroxyl groups can enable the modified PET to cross-link with hydrogen bonds, inhibit PET crystallization, destroy the regularity of PET, reduce light scattering, and thus improve the light transmittance of modified PET. The large amount of triazine and phenyl structures work together to form a π-π stacking effect, which increases the rigidity of modified PET and thus improves the structural stability of the insect-proof net. In addition, the modified PET structure contains a large amount of nitrogen element. When the modified PET is burned, it can decompose to produce nitrogen-containing gas, which can capture active free radicals, thereby reducing the burning intensity and improving the flame retardant performance of the insect-proof net. Attached Figure Description

[0030] Figure 1 This is a partial schematic diagram of the insect-proof netting in an embodiment of this application;

[0031] Figure 2 The proton NMR spectrum of the compound shown in Formula II in Example 1 of this application;

[0032] Figure 3 The 1H NMR spectrum of the functional polyol prepared in Example 1 of this application;

[0033] Attached diagram labels: 1. Edge sealing; 2. Warp yarn; 3. Weft yarn; 4. Embossing. Detailed Implementation

[0034] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0035] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0036] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of the invention. Various modifications and variations to the specific embodiments described in this specification are apparent to those skilled in the art without departing from the scope or spirit of the invention. Other embodiments derived from this specification will be apparent to those skilled in the art. This application specification and embodiments are merely exemplary.

[0037] It should be noted that the operations such as "drying", "filtering", and "stirring" described in this invention are conventional operations for those skilled in the art, and should be selected according to actual operation.

[0038] The PET was purchased from Shenzhen GEM Optoelectronic Materials Co., Ltd.

[0039] Preparation Example 1

[0040] Reference Figures 2-3 The preparation method of functional polyols includes the following steps:

[0041] A1. Under a nitrogen atmosphere, 0.1 mol of cyanuric chloride was dissolved in 200 mL of acetonitrile. The solution was cooled to -3°C in an ice bath. Then, 0.23 mol of resorcinol, 0.11 mol of aniline, and 0.6 mol of sodium bicarbonate were added. After the additions were complete, the solution was heated to room temperature and reacted for 6 hours. Then, 0.28 mol of cyanuric chloride was added, and the mixture was stirred for another 6 hours. After the reaction was complete, the solution was filtered, concentrated under reduced pressure, and subjected to column chromatography to obtain the compound shown in Formula II. The 1H NMR spectrum is shown below. Figure 2

[0042]

[0043] A2. Under a nitrogen atmosphere, 0.1 mol of the compound shown in Formula II from step A1 was mixed with 300 mL of toluene. The mixture was cooled to -3°C in an ice bath, and 0.42 mol of ethanolamine and 0.5 mol of sodium bicarbonate were added. The mixture was stirred at a constant temperature for 6.5 h. After the reaction was completed, the mixture was filtered, concentrated under reduced pressure, and subjected to column chromatography to obtain a functional polyol with the structure shown in Formula I. The 1H NMR spectrum is shown in [reference needed]. Figure 3

[0044]

[0045] Preparation Example 2

[0046] The preparation method of functional polyols includes the following steps:

[0047] A1. Under a nitrogen atmosphere, 0.1 mol of cyanuric chloride was dissolved in 200 mL of acetonitrile, and the mixture was cooled to -3°C in an ice bath. 0.34 mol of resorcinol and 0.4 mol of sodium bicarbonate were added. After the additions were complete, the mixture was heated to room temperature and reacted for 6 hours. Then, 0.28 mol of cyanuric chloride was added, and the mixture was stirred for another 6 hours. After the reaction was complete, the mixture was filtered, concentrated under reduced pressure, and subjected to column chromatography to obtain the compound represented by Formula III.

[0048]

[0049] A2. Under a nitrogen atmosphere, 0.1 mol of the compound shown in Formula III from step A1 was mixed with 300 mL of toluene. The mixture was cooled to -3°C in an ice bath, and 0.6 mol of ethanolamine and 0.62 mol of sodium bicarbonate were added. The mixture was stirred at a constant temperature for 6.5 h. After the reaction was completed, the mixture was filtered, concentrated under reduced pressure, and subjected to column chromatography to obtain a functional polyol with the structure shown in Formula IV.

[0050]

[0051] Preparation Example 3

[0052] The preparation method of the functional polyol is the same as that in Preparation Example 1, except that equimolar resorcinol is used instead of ethanolamine.

[0053] Preparation Example 4

[0054] The preparation method of functional polyols includes the following steps:

[0055] A1. Under a nitrogen atmosphere, 0.1 mol of cyanuric chloride was dissolved in 200 mL of acetonitrile. The solution was cooled to -3°C in an ice bath, and then 0.23 mol of resorcinol, 0.11 mol of aniline, and 0.6 mol of sodium bicarbonate were added. After the addition was complete, the solution was heated to room temperature and reacted for 6 hours. After the reaction was completed, the solution was filtered, concentrated under reduced pressure, and purified by column chromatography to obtain a functional polyol with the structure shown in Formula V.

[0056]

[0057] Preparation Example 5

[0058] The preparation method of modified PET includes the following steps: Under N2 atmosphere, 10g of terephthalic acid, 12g of ethylene glycol, 3g of functional polyol and 0.06g of antimony trioxide are mixed, pressurized to 0.02MPa, heated to 230℃, and reacted for 3h. Then, vacuum is applied to a pressure of 2400Pa, and the reaction continues for 1.6h. Then, the temperature is raised to 270℃, the pressure is maintained at 70Pa, and the mixture is stirred at a constant temperature for 1.7h to obtain modified PET.

[0059] The functional polyol was prepared in Preparation Example 1.

[0060] Preparation Example 6

[0061] The preparation method of modified PET is the same as that in Preparation Example 5, except that the functional polyol is prepared from Preparation Example 2.

[0062] Preparation Example 7

[0063] The preparation method of modified PET is the same as that in Preparation Example 5, except that the functional polyol is prepared in Preparation Example 3.

[0064] Preparation Example 8

[0065] The preparation method of modified PET is the same as that in Preparation Example 5, except that the functional polyol is prepared in Preparation Example 4.

[0066] Example 1

[0067] Reference Figure 1 This embodiment provides an insect-proof net, which is composed of multiple warp yarns 2 and multiple weft yarns 3; the edge of the insect-proof net has a sealing edge 1, which covers the ends of the weft yarns 3; multiple indentations 4 are provided on the sealing edge 1; the ends of each weft yarn 3 are fused together; the width of the insect-proof net is 12cm; the sealing edge 1 is a film; and the warp yarns 2 and weft yarns 3 are monofilaments.

[0068] By weight, the warp yarn 2 and weft yarn 3 are obtained by remelting and spinning a mixture of 2.5 parts UV-1164 and 110 parts modified PET.

[0069] The modified PET was prepared in Preparation Example 5.

[0070] Example 2

[0071] An insect-proof net is composed of multiple warp yarns 2 and multiple weft yarns 3; the edge of the insect-proof net has a sealing edge 1, which covers the ends of the weft yarns 3; multiple indentations 4 are provided on the sealing edge 1; the ends of each weft yarn 3 are fused together; the width of the insect-proof net is 7cm; the sealing edge 1 is a film; and the warp yarns 2 and weft yarns 3 are monofilaments.

[0072] By mass percentage, the warp yarn 2 and weft yarn 3 are obtained by remelting and spinning a mixture of 0.5 parts UV-1164 and 90 parts modified PET.

[0073] The modified PET was prepared in Preparation Example 5.

[0074] Example 3

[0075] An insect-proof net is composed of multiple warp yarns 2 and multiple weft yarns 3; the edge of the insect-proof net has a sealing edge 1, which covers the ends of the weft yarns 3; multiple indentations 4 are provided on the sealing edge 1; the ends of each weft yarn 3 are fused together; the width of the insect-proof net is 20cm; the sealing edge 1 is a film; and the warp yarns 2 and weft yarns 3 are monofilaments.

[0076] By mass percentage, the warp yarn 2 and weft yarn 3 are obtained by remelting and spinning a mixture of 4 parts UV-1164 and 130 parts modified PET.

[0077] The modified PET was prepared in Preparation Example 5.

[0078] Example 4

[0079] An insect-proof net, the specific implementation method is the same as in Example 1, except that the modified PET is prepared by Preparation Example 6.

[0080] Example 5

[0081] An insect-proof net, the specific implementation method is the same as in Example 1, except that the modified PET is prepared by Example 7.

[0082] Example 6

[0083] An insect-proof net, the specific implementation method is the same as in Example 1, except that the modified PET is prepared by Example 8.

[0084] Comparative Example 1

[0085] An insect-proof net, the specific implementation method is the same as in Example 1, except that an equal mass of PET is used instead of modified PET.

[0086] Performance testing:

[0087] (1) Elastic modulus: Cut the insect net into 5cm×5cm test pieces and test according to ASTM D790 standard. The larger the elastic modulus, the stronger the rigidity of the insect net.

[0088] (2) Flame retardant performance: The oxygen index of the insect-proof net is tested according to GB / T2406-93;

[0089] The insect-proof nets of each embodiment and comparative example were tested according to the above test methods (1) to (2), and the test results are shown in Table 1.

[0090] Table 1

[0091] Elastic modulus / GPa Oxygen Index / % Example 1 4.9 41.1 Example 2 4.6 40.5 Example 3 4.8 42.6 Example 4 5.7 41.8 Example 5 5.5 40.2 Example 6 4.5 36.5 Comparative Example 1 2.5 21.9

[0092] According to the data in Table 1, the insect nets prepared in Examples 1 to 5 have a certain rigidity and flame retardant properties. In Example 6, the flame retardant properties of the insect net decreased due to the reduction in nitrogen content in the modified PET structure caused by the alteration of the structure of the functional polyol. In Comparative Example 1, the rigidity of the insect net decreased because an equal mass of PET was used instead of the modified PET. When the insect net was unfolded, it could not maintain the accordion-like structure and collapsed. Furthermore, the flame retardant properties of the insect net decreased.

[0093] (3) Light transmittance: PET film is produced by using a fully automatic vacuum drum, extruder, and biaxial stretching unit. The film temperature is controlled at 95℃, the thickness is controlled at 0.2mm, and the size is 120mm×120mm. The light transmittance of the film is tested using a LAMBDA35 spectrophotometer.

[0094] The modified PET and PET prepared in Examples 5 to 8 were tested according to the above method (3), and the test results are shown in Table 2.

[0095] Table 2

[0096] Light transmittance / % PET 80.39 Preparation Example 5 98.24 Preparation Example 6 89.68 Preparation Example 7 92.33 Preparation Example 8 97.47

[0097] According to the data in Table 2, the modified PET prepared in Preparation Examples 5 and 8 has good light transmittance, which allows more light to enter the room when the insect net is used, thus improving the growth of crops. In Preparation Example 6, the use of resorcinol instead of aniline increased the content of active hydroxyl groups in the functional polyol structure, resulting in excessive crosslinking density of the modified PET, thereby reducing the light transmittance of the modified PET. In Preparation Example 7, the use of equimolar resorcinol instead of ethanolamine increased the content of rigid benzene ring structures in the modified PET structure, which aggravated crystallization and microphase separation, thus reducing the transparency of the modified PET.

[0098] Finally, it should be noted that the above specific embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. An insect-proof net, characterized in that, The insect-proof net is composed of multiple warp yarns (2) and multiple weft yarns (3); the edge of the insect-proof net has a sealing edge (1) covering the end of the weft yarn (3); multiple indentations (4) are provided on the sealing edge (1); by mass fraction, the warp yarns (2) and weft yarns (3) are made by mixing and remelting 0.5 to 4 parts of UV-resistant additives and 90 to 130 parts of modified PET; The method for preparing the modified PET includes the following steps: under an inert protective gas atmosphere, terephthalic acid, ethylene glycol, functional polyol and catalyst are mixed, pressurized to 0.01~0.03MPa, heated to 220~250℃, and reacted for 2~4h. Then, a vacuum is drawn to a pressure of 2300~2500Pa, and the reaction continues for 1.2~1.8h. Then, the temperature is raised to 260~280℃, the pressure is maintained at 50~100Pa, and the mixture is stirred at a constant temperature for 1.5~2h to obtain the modified PET. The functional polyol comprises the structure shown in Formula I: （Ⅰ）； The preparation method of the functional polyol includes the following steps: A1. Under an inert protective gas atmosphere, the first batch of cyanuric chloride was dissolved in acetonitrile, cooled to -5~0℃ in an ice bath, and resorcinol, aniline, and an acid-binding agent were added. After the addition was complete, the temperature was raised to room temperature and reacted for 5~7 hours. Then, the second batch of cyanuric chloride was added and the mixture was stirred for another 5~7 hours. After the reaction was completed, the mixture was filtered, concentrated under reduced pressure, and subjected to column chromatography to obtain the compound represented by Formula II. （Ⅱ）； A2. Under an inert protective gas atmosphere, the compound shown in Formula II in step A1 is mixed with toluene, cooled to -5~0℃ in an ice bath, ethanolamine and acid-binding agent are added, and the mixture is stirred at a constant temperature for 6~7h. After the reaction is completed, the mixture is filtered, concentrated under reduced pressure, and obtained by column chromatography. In step A1, the molar ratio of the first batch of cyanuric chloride, aniline, and resorcinol is 1:(1~1.2):(2.2~2.5); In step A1, the molar ratio of the second batch of cyanuric chloride to resorcinol is (1~1.3):1; In step A2, the molar ratio of the compound represented by formula II to ethanolamine is 1:(4~4.5).

2. The insect-proof net according to claim 1, characterized in that, The ends of each of the weft yarns (3) are fused together.

3. The insect-proof net according to claim 1, characterized in that, The edge sealing (1) is a film or webbing.

4. The insect-proof net according to claim 1, characterized in that, The width of the insect-proof net is 7-20cm.

5. The insect-proof net according to claim 1, characterized in that, The warp yarn (2) and weft yarn (3) are monofilaments.

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