Temperature-sensitive color-changing wear-resistant monofilament as well as preparation method and application thereof

Abstract

The invention provides a temperature-sensitive color-changing wear-resistant monofilament as well as a preparation method and application thereof. The temperature-sensitive color-changing wear-resistant monofilament has an excellent visual early warning function and wear resistance. The temperature-sensitive color-changing wear-resistant monofilament can be used for further preparing a woven mesh pipe, when the monofilament is put into application, when a wire harness making contact with the multifunctional woven mesh pipe breaks down and generates abnormal heating, the multifunctional woven mesh pipe can play a warning role in a user or a maintainer through visual change of the color, and the service life of the user or the maintainer is prolonged. Technicians are assisted to quickly find the accurate position of abnormal heating, and the intelligent response to the temperature is given to the wire harness protection sleeve.

Description

Technical Field

[0001] The invention relates to the technical field of new materials, and in particular to a temperature-sensitive color-changing wear-resistant monofilament and a preparation method and application thereof. Background Art

[0002] Thermochromic materials are materials that can change color as the temperature changes. This property makes them widely used in many fields. The basic principle of thermochromic materials is to change the molecular structure of organic matter through electron transfer at a specific temperature, thereby achieving color change. This material is not only brightly colored, but also can change from "colored" to "colorless", which is not available in other types of color-changing materials. Thermochromic materials have a wide range of color changes. The applications of these materials include but are not limited to medical testing, wearable displays, safety protection, human body temperature sensing products, and anti-counterfeiting design. Due to its unique temperature-sensitive color-changing properties, thermochromic materials have shown broad application prospects in many fields such as medical, textiles, and coatings, bringing new functions and aesthetics to these fields.

[0003] However, the prior art still lacks a wire harness type temperature sensitive color changing material with excellent performance. Summary of the invention

[0004] The purpose of the present invention is to provide a temperature-sensitive color-changing wear-resistant monofilament and a preparation method and application thereof, which has an excellent visual early warning function.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The present invention provides a method for preparing a temperature-sensitive color-changing wear-resistant monofilament, comprising the following steps:

[0007] S1, mixing and granulating the thermochromic powder, PP resin and dispersant to obtain a thermochromic masterbatch;

[0008] S2. Mix the thermochromic masterbatch, PP resin, nitrogen-phosphorus composite synergistic halogen-free flame retardant and anti-aging agent, and heat and draw to obtain the thermochromic wear-resistant monofilament.

[0009] In the present invention, the addition of the nitrogen and phosphorus composite synergistic halogen-free flame retardant can give the temperature-dependent monofilament high-efficiency flame retardant properties, and melamine polyphosphate (MPP), melamine cyanurate (MCA), ammonium polyphosphate, etc. can be selected. The anti-aging agent of the present invention is mainly used to delay the thermal degradation caused by thermal oxidation aging during the processing and preparation process and the use of the product. It is mainly a phenolic heat stabilizer, and BASF's 1010, 1035 and other hydroxylated aromatic compounds.

[0010] In the present invention, the PP resin is a polypropylene resin, and a drawing grade or extrusion grade PP resin can be selected. The available product models include H730F of SK of South Korea, S1003 of Shanghai SECCO, S1005 and S2035 of Formosa Petrochemical, and PPH-T03 of Daqing Petrochemical.

[0011] Preferably, the dispersant contains stearamide dispersant and higher alcohol dispersant;

[0012] The stearamide dispersant is selected from one or both of erucamide and hexenyl bisstearamide;

[0013] The higher fatty alcohol dispersant is selected from one or both of octadecanoic acid glyceryl monoester and tristearic acid glyceryl.

[0014] The stearamide and the higher alcohol can significantly improve lubricity, which is important for reducing friction and protecting mechanical parts from wear. This combination can also improve the thermal stability of the material.

[0015] Preferably, the weight ratio of the thermochromic powder, PP resin and dispersant is 1-10:89-98:0.1-1.

[0016] Preferably, the granulation comprises adopting the following parameters:

[0017] The main unit heating temperature is 180~210℃;

[0018] The PP resin is dried at 60-80° C. for 3-4 hours before use.

[0019] Preferably, the nitrogen-phosphorus composite synergistic halogen-free flame retardant is selected from one or more of melamine polyphosphate, melamine cyanurate or ammonium polyphosphate.

[0020] Preferably, the weight ratio of the thermochromic masterbatch, PP resin, nitrogen-phosphorus composite synergistic halogen-free flame retardant and anti-aging agent is 10-40:50-90:1-4:1-3.

[0021] Preferably, the heating wire drawing includes adopting the following parameters:

[0022] The main machine heating temperature is 180-220°C, the single filament diameter is 0.20-0.50mm, the cooling liquid temperature is 30-48°C, the hot water drawing temperature is 94-98°C, the heat setting temperature is 150-200°C, the drawing speed is 80-100m / min, and the single filament drawing ratio is 5.2-6.8.

[0023] In the present invention, if the stretching ratio of the monofilament is too low (<5.0), the orientation degree of the macromolecules is not high, the crystallinity is low, and the breaking strength of the monofilament is relatively low. However, if the stretching ratio is too large, the macromolecules will slip and break, and the breaking strength of the monofilament will decrease. If the stretching ratio is increased blindly, the movement of the macromolecules will obviously not keep up with the stretching deformation process. Due to the existence of weak links, the monofilament is easy to break during the stretching process. Therefore, setting the stretching ratio within the range of 5.2-6.8 can not only allow the monofilament to have a certain breaking strength, but also avoid production anomalies such as broken wires due to excessive stretching during the production process.

[0024] The present invention also provides a temperature-sensitive color-changing wear-resistant monofilament prepared by the preparation method.

[0025] The present invention also provides the use of the temperature-sensitive color-changing wear-resistant monofilament in the preparation of a braided mesh tube.

[0026] Technical effects and advantages of the present invention:

[0027] In the present invention, under high temperature, the color-changing dye and the developer are dissolved and dispersed in the solvent, and the system presents a white state. When the temperature is lowered, the solvent gradually solidifies, the color-changing dye and the developer approach each other, and under the action of the developer, the color-changing dye undergoes structural changes, so that the system shows color. The temperature-changing powder manufactured by commercially available microcapsule technology is added to the matrix PP resin by adding the temperature-changing powder, adding a small amount of dispersant as an auxiliary auxiliary agent, and using a single screw extruder to extrude and pelletize to obtain a temperature-changing color masterbatch. By adding the temperature-changing color masterbatch, the temperature-sensitive color-changing wear-resistant monofilament is obtained by melt extrusion and liquid-cooling stretching, which has excellent temperature-changing performance and wear resistance.

[0028] The temperature-sensitive color-changing wear-resistant monofilament of the present invention can be used to further prepare a braided mesh tube. When it is put into use, when a wiring harness in contact with the multifunctional braided mesh tube fails and abnormal heat occurs, the multifunctional braided mesh tube can serve as a warning to users or maintenance personnel through visual color changes, thereby assisting technicians to quickly find the exact location of the abnormal heat. DETAILED DESCRIPTION

[0029] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0030] Example 1

[0031] 1. Preparation plan of thermochromic masterbatch: 4 parts of 3PC thermochromic powder, 95 parts of PP resin, PPH-T03 of Daqing Petrochemical, 0.5 parts of erucic acid amide and 0.5 parts of octadecanoic acid glycerol monoester. Use single screw extruder for extrusion granulation, set the main machine heating temperature to 180℃, 185℃, 190℃, 195℃, 200℃, extrude and cut into strips, dry for 4 hours and then bag. PP resin is dried at 60℃ for 4h.

[0032] 2. Preparation plan of temperature-sensitive color-changing wear-resistant flame-retardant monofilament: 20 parts of temperature-sensitive color-changing masterbatch, 77 parts of PP resin, 1.0 parts of melamine cyanurate flame-retardant masterbatch, 2.0 parts of 1010 anti-aging masterbatch, masterbatch and resin particles are dried at 60℃ for 4 hours. PP wear-resistant and flame-retardant monofilaments are obtained by melt extrusion, cooling and stretching. Single screw extruder is used for extrusion and drawing, and the main machine heating temperature is set to 210℃, 220℃, 220℃, 230℃, 230℃, 230℃, 233℃, 235℃. The monofilament diameter is 0.25±0.02mm, the cooling liquid temperature is 32℃, the hot water drawing temperature is 98℃, the heat setting temperature is 150℃, the drawing speed is 90m / min, and the monofilament stretching ratio is 5.5.

[0033] 3. Preparation plan of multifunctional braided mesh tube: 4 temperature-sensitive color-changing, wear-resistant and flame-retardant monofilament yarns are twisted and woven into a mesh tube, with 48 spindles.

[0034] Example 2

[0035] The only difference from Example 1 is that the number of thermochromic masterbatch in the preparation scheme of the thermochromic wear-resistant monofilament is changed from 20 to 30 parts, and the number of PP resin is changed from 77 to 67 parts.

[0036] Example 3

[0037] The only difference from Example 1 is that the number of thermochromic masterbatch in the preparation scheme of the thermochromic wear-resistant monofilament is changed from 30 to 40 parts, and the number of PP resin is changed from 77 to 57 parts.

[0038] Example 4

[0039] The only difference from Example 1 is that the amount of melamine cyanurate flame retardant masterbatch in the preparation scheme of the temperature-sensitive color-changing wear-resistant monofilament is changed from 1.0 part to 1.5 parts.

[0040] Example 5

[0041] The only difference from Example 1 is that the main engine temperature in the preparation scheme of the temperature-sensitive color-changing wear-resistant monofilament is changed to 220°C, 220°C, 220°C, 230°C, 230°C, 230°C, 235°C, 235°C. The cooling liquid temperature is changed from 32°C to 37°C, the monofilament stretching ratio is changed from 5.5 to 6.3, and the heat setting temperature is changed from 150°C to 160°C.

[0042] Example 6

[0043] The only difference from Example 1 is that the main engine temperature in the preparation scheme of the temperature-sensitive color-changing wear-resistant monofilament is changed to 220°C, 220°C, 220°C, 230°C, 230°C, 240°C, 240°C, 240°C, the cooling liquid temperature is changed from 32°C to 42°C, the monofilament stretching ratio is changed from 5.5 to 7.0, and the heat setting temperature is changed from 150°C to 170°C.

[0044] Comparative Example 1

[0045] The only difference from Example 1 is that the PP resin in the preparation scheme of the temperature-sensitive color-changing wear-resistant monofilament is changed from the original 77 parts to 78 parts, and no flame retardant masterbatch is added.

[0046] Comparative Example 2

[0047] The only difference from Example 1 is that the PP resin in the preparation scheme of the temperature-sensitive color-changing wear-resistant monofilament is changed from the original 77 parts to 79 parts, and no anti-aging masterbatch is added.

[0048] Experimental example

[0049] The braided mesh tube prepared in the above embodiment was subjected to a wear resistance test according to standard ISO 6722-1 and a horizontal burning test according to standard FMVSS 302-2021. The braided mesh tube was subjected to real-life simulation and thermal aging (100°C / 120H) evaluation. It was then observed whether it had a visual early warning function. Detailed parameters are shown in Table 1.

[0050] Table 1 Test results

[0051]

[0052] As can be seen from Table 1, appropriately increasing the stretch ratio is effective in improving wear resistance, but too high a stretch ratio will reduce wear resistance. This is because too high a stretch ratio will cause the macromolecules to slip and break while destroying the original crystalline structure. This leads to a decrease in the wear resistance of the braided mesh tube. The application of flame retardants makes the braided mesh tube have a certain flame retardant effect, and the presence of flame retardants has little effect on the color change effect of the temperature-sensitive color-changing wear-resistant monofilament. The addition of anti-aging agents can prevent the material from yellowing due to thermal oxygen aging, thereby affecting the temperature-changing color and losing the temperature-changing function. The change of the temperature-sensitive color-changing wear-resistant monofilament from colored to nearly colorless indicates that the visual warning function is effective, and it can be seen from Table 1 that the visual warning response time of the multifunctional braided mesh tube is shortened as the proportion of the temperature-changing masterbatch added increases, indicating that the visual warning function of the temperature-sensitive color-changing wear-resistant monofilament becomes sensitive as the proportion of the temperature-changing masterbatch increases.

[0053] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for preparing a temperature-sensitive color-changing wear-resistant monofilament, characterized in that: The following steps are involved: S1, mixing and granulating the thermochromic powder, PP resin and dispersant to obtain a thermochromic masterbatch; S2, mixing the thermochromic masterbatch, PP resin, nitrogen-phosphorus composite synergistic halogen-free flame retardant and anti-aging agent, heating and drawing to obtain the thermochromic wear-resistant monofilament.

2. The preparation method according to claim 1, characterized in that: The dispersant contains a stearamide dispersant and a higher alcohol dispersant; The stearamide dispersant is selected from one or two of erucamide and hexenyl bisstearamide; The higher fatty alcohol dispersant is selected from one or both of octadecanoic acid glyceryl monoester and tristearic acid glyceryl.

3. The preparation method according to claim 2, characterized in that: The weight ratio of the thermochromic powder, PP resin and dispersant is 1-10:89-98:0.1-1.

4. The preparation method according to claim 1, characterized in that: The granulation comprises the following parameters: The main unit heating temperature is 180~210℃; The PP resin is dried at 60-80° C. for 3-4 hours before use.

5. The preparation method according to claim 1, characterized in that: The nitrogen-phosphorus composite synergistic halogen-free flame retardant is selected from one or more of melamine polyphosphate, melamine cyanurate or ammonium polyphosphate.

6. The preparation method according to claim 1, characterized in that: The weight ratio of the thermochromic masterbatch, PP resin, nitrogen-phosphorus composite synergistic halogen-free flame retardant and anti-aging agent is 10-40:50-90:1-4:1-3.

7. The preparation method according to claim 1, characterized in that: The heating wire drawing includes adopting the following parameters: The main machine heating temperature is 180-220°C, the single filament diameter is 0.20-0.50mm, the cooling liquid temperature is 30-48°C, the hot water drawing temperature is 94-98°C, the heat setting temperature is 150-200°C, the drawing speed is 80-100m / min, and the single filament drawing ratio is 5.2-6.

8.

8. Thermochromic wear-resistant monofilament prepared by the preparation method according to any one of claims 1 to 7.

9. Use of the temperature-sensitive color-changing wear-resistant monofilament according to claim 8 in the preparation of a braided mesh tube.

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