TPU soft rubber color master batch and preparation method thereof

Abstract

The invention relates to the technical field of plastic color master batches, and particularly discloses a TPU (Thermoplastic Polyurethane) soft rubber color master batch and a preparation method thereof. The TPU soft rubber color master batch is prepared from the following raw materials in parts by weight: 50-70 parts of TPU; 25 to 50 parts of pigment; 1-5 parts of an additive; 1-3 parts of zinc stearate; 0.5 to 2 parts of a silane coupling agent; 2-5 parts of modified polyethylene wax; the modified polyethylene wax is prepared by the following steps: S1, putting a polyethylene wax raw material into a stirring container, heating and melting, then adding maleic anhydride and an initiator, and heating and reacting to obtain a modified polyethylene wax crude product; and S2, adding toluene into the modified polyethylene wax crude product in the step S1, dissolving, cooling, adding acetone, stirring, carrying out suction filtration, washing and drying to obtain a modified polyethylene wax finished product. The TPU soft rubber color master batch provided by the invention has relatively stable dispersion uniformity, can avoid harsh and high-energy-consumption processing requirements, and is more suitable for processing and production requirements.

Description

Technical Field

[0001] The present application relates to the technical field of plastic masterbatches, and more specifically, to a TPU soft glue masterbatch and a preparation method thereof. Background Art

[0002] TPU soft-gel masterbatch is a coloring additive specifically designed for thermoplastic polyurethane (TPU) materials. By fully combining high-quality pigments or dyes with the TPU matrix, the product is concentrated in a concentrated form to provide precise color during the production of TPU products. TPU soft-gel masterbatch not only improves the appearance of TPU products but also simplifies the production process, improving production efficiency and product quality. This makes it widely used in applications such as footwear, films, and pipes.

[0003] TPU masterbatches primarily consist of the following ingredients: pigments, which are highly concentrated pigments used to color the TPU material; a carrier, typically a thermoplastic polyurethane (TPU) elastomer, which serves as the masterbatch's base and ensures good compatibility between the pigment and the TPU; and additives, including various additives such as dispersants and stabilizers, which improve the masterbatch's performance and processing characteristics. The manufacturing process for TPU masterbatches involves the following steps: fine dispersion, which finely disperses the pigment within the TPU resin to ensure uniform distribution; and extrusion and pelletizing, which extrude and pelletize the dispersed material through an extruder to form the masterbatch.

[0004] Among them, the dispersion uniformity of masterbatch is particularly important. Dispersion uniformity of masterbatch refers to the ability of its internal pigment particles to be evenly distributed in the carrier resin and substrate. It is manifested as the pigment is fully refined and stably present in the entire system in a small, independent state. When the dispersion uniformity of the masterbatch is poor, it will lead to mottled color, affecting product quality and increasing the scrap rate.

[0005] At present, most of the improvement measures on the market achieve a highly uniform dispersion effect by regulating the melt temperature, shear force, time and extruder speed. Although this can bring certain improvements, it fails to fundamentally solve the problem of poor dispersion uniformity. In addition, it is costly, unstable and has limited efficiency.

[0006] Therefore, it is urgent to propose a solution to solve the above technical problems. Summary of the Invention

[0007] In order to more stably improve the dispersion uniformity of masterbatch and better adapt to the needs of processing and production, the present application provides a TPU soft rubber masterbatch and a preparation method thereof.

[0008] In the first aspect, the present application provides a TPU soft glue masterbatch, which adopts the following technical solution: A TPU soft rubber masterbatch is made from the following raw materials in parts by weight: TPU 50-70 parts; Pigment 25-50 parts; 1-5 parts of additives; 1-3 parts of zinc stearate; Silane coupling agent 0.5-2 parts; 2-5 parts of modified polyethylene wax; The modified polyethylene wax is prepared by the following steps: S1. Place the polyethylene wax raw material in a stirring container, heat and melt it, then add maleic anhydride and an initiator, and heat the reaction to obtain a crude modified polyethylene wax; S2. Add toluene to dissolve the crude modified polyethylene wax obtained in step S1, add acetone after cooling, stir, filter, wash, and dry to obtain a finished modified polyethylene wax.

[0009] By employing the above technical solution, zinc stearate primarily serves as a dispersant and lubricant in the masterbatch, promoting uniform pigment dispersion, reducing agglomeration, and improving processing fluidity, thereby enhancing product quality. The addition of a silane coupling agent can also reduce the masterbatch's melt viscosity, improving its fluidity and processing performance. Its molecular composition and structure significantly enhance the pigment's dispersibility and binding properties with other ingredients. Modified polyethylene wax is obtained by grafting maleic anhydride onto polyethylene wax. The carboxyl and anhydride groups in the maleic anhydride react with the polyethylene wax molecular chain to form new chemical bonds, thereby improving the compatibility between the polyethylene wax and other raw materials and enhancing the pigment's uniformity and stability. In the raw material system of TPU soft rubber masterbatch, the combination of zinc stearate, silane coupling agent and modified polyethylene wax can bring excellent compounding and synergistic effect to each other, bring bidirectional effect to TPU and pigment, and coordinate the compatibility of various raw materials to form a synergistic effect of chemical bonding-physical lubrication-rheological regulation, so that the prepared TPU soft rubber masterbatch has relatively stable dispersion uniformity; at the same time, this interaction between raw materials is more adapted to the needs of processing and production, can avoid harsh and high-energy consumption processing requirements, and the overall application effect is significant.

[0010] Preferably, the weight ratio of the zinc stearate, the silane coupling agent and the modified polyethylene wax is 2:1:3.

[0011] By adopting the above technical solution, the coordination system formed by zinc stearate, silane coupling agent and modified polyethylene wax in TPU soft rubber masterbatch is relatively uniform and stable, and has better compatibility and dispersibility with other raw materials, thereby making the final TPU soft rubber masterbatch have better dispersion uniformity.

[0012] Preferably, in the preparation of the modified polyethylene wax, the average molecular weight of the polyethylene wax raw material is 3000-5000.

[0013] By adopting the above technical solution, if the average molecular weight of the polyethylene wax raw material is too high, the resulting modified polyethylene wax, when used with zinc stearate and a silane coupling agent, will result in high viscosity and poor wettability. If the average molecular weight of the polyethylene wax raw material is too low, the resulting modified polyethylene wax, when used with zinc stearate and a silane coupling agent, will result in low viscosity and insufficient shear stress, both of which will affect the stable and excellent dispersion effect. However, the modified polyethylene wax prepared with the above average molecular weight, when used with zinc stearate and a silane coupling agent, will form a system with better lubricity and dispersibility, ultimately producing a TPU soft rubber masterbatch with excellent dispersion uniformity.

[0014] Preferably, the raw materials of the TPU soft glue masterbatch are further added with 4-6 parts by weight of a functional additive, the functional additive is composed of nano-montmorillonite and nano-barium sulfate, and the weight ratio of nano-montmorillonite to nano-barium sulfate is (1.2-1.8):1.

[0015] By adopting this technical solution, the layered structure and adsorption capacity of nano-montmorillonite enable it to adsorb and disperse pigment particles, preventing pigment agglomeration and precipitation, thereby enhancing pigment dispersion performance. The inert nature of barium sulfate reduces interactions between pigments, preventing agglomeration and ensuring color consistency and stability in the masterbatch. Furthermore, when used as a functional additive, nano-montmorillonite and nano-barium sulfate can provide excellent synergistic effects. In addition to their excellent individual effects, they not only increase the shear force transmitted to pigment agglomerates, but also grind and impact them, thereby making them easier to break up and exhibiting better dispersibility. Furthermore, nano-montmorillonite and nano-barium sulfate can enhance the combined system of zinc stearate, silane coupling agent, and modified polyethylene wax, forming a multi-system combination that significantly improves the dispersion uniformity of TPU soft rubber masterbatch.

[0016] Preferably, the weight ratio of the nano-montmorillonite to the nano-barium sulfate is 1.5:1.

[0017] By adopting the above technical solution, when the nano-montmorillonite and nano-barium sulfate in the above proportion are used in combination, the functional additives can be evenly dispersed in the mixing system of the TPU soft glue masterbatch, and the coordination and enhancement effect with zinc stearate, silane coupling agent and modified polyethylene wax is better, and the dispersion uniformity of the TPU soft glue masterbatch obtained is also better.

[0018] Preferably, the particle size of the nano-montmorillonite and nano-barium sulfate is 30-50 nm.

[0019] By adopting the above technical solution, the particle size of nano-montmorillonite and nano-barium sulfate is directly related to their effect on the pigment in the TPU soft rubber masterbatch, and the nano-montmorillonite and nano-barium sulfate in the above particle size range can ensure that the functional additives have a better corresponding effect on the pigment after application, thereby making the final TPU soft rubber masterbatch have excellent dispersion uniformity.

[0020] Preferably, the pigment is one or a combination of titanium dioxide, carbon black, cadmium red, cadmium yellow, titanium dioxide, red iron oxide and yellow iron oxide.

[0021] By adopting the above technical solution, pigment is the main functional component of masterbatch. The coloring effect is achieved by evenly loading the pigment into the resin to form aggregates. The above-mentioned raw materials are all suitable for the preparation of TPU soft rubber masterbatch and can provide stable color coverage during the application process.

[0022] Preferably, the additive is one or a combination of stabilizers, antioxidants, flame retardants, antistatic agents and slip agents.

[0023] By adopting the above technical solution, the above types of additives can be selected and combined according to actual application needs, and all of them can be evenly dispersed in the TPU soft rubber masterbatch and play an excellent and stable role of their own, thereby obtaining TPU soft rubber masterbatch with different functional emphasis, so that the TPU soft rubber masterbatch has excellent applicability.

[0024] In a second aspect, the present application provides a method for preparing TPU soft glue masterbatch, which adopts the following technical solution: A method for preparing a TPU soft rubber masterbatch comprises: (1) preparing raw materials including TPU, pigment, additive, zinc stearate, silane coupling agent and modified polyethylene wax according to a proportion; (2) After the TPU, pigment, additive, zinc stearate, silane coupling agent and modified polyethylene wax in step (1) are mixed and dispersed, the mixed material is added to a twin-screw extruder for melt extrusion, and pelletized after cooling and solidification to obtain TPU soft rubber masterbatch.

[0025] By adopting the above technical solution, the above preparation method is simple to operate. After the raw materials are mixed, they are melt-extruded in one step, which can enable the zinc stearate, silane coupling agent and modified polyethylene wax to exert an excellent synergistic effect, thereby obtaining a TPU soft rubber masterbatch with excellent quality and stability, which is more suitable for large-scale industrial production as a whole.

[0026] Preferably, in step (2), the melt extrusion temperature is 190-220°C.

[0027] By adopting the above technical solution, temperature control during the melt extrusion process has a direct impact on the pigment dispersion effect; temperatures that are too high or too low will affect the uniformity of the dispersion of pigment particles in the resin; and the melt extrusion temperature within the above range can ensure that the material is completely melted, thereby achieving a better dispersion effect.

[0028] In summary, this application has the following beneficial effects: 1. In the raw material system of TPU soft rubber masterbatch, the present application utilizes zinc stearate, a silane coupling agent, and a modified polyethylene wax in combination to form a synergistic effect of chemical bonding, physical lubrication, and rheological control, thereby enabling the prepared TPU soft rubber masterbatch to have relatively stable dispersion uniformity. Furthermore, the dispersion uniformity is improved by the interaction between the raw materials, thereby avoiding harsh and energy-intensive processing requirements and being more adaptable to processing and production needs. 2. This application utilizes functional additives composed of nano-montmorillonite and nano-barium sulfate to prevent pigment particle agglomeration and precipitation, increase the shear force imparted to pigment aggregates, and grind and impact them, thereby making them easier to break up and enhancing pigment dispersion. Furthermore, the nano-montmorillonite and nano-barium sulfate enhance the combined system of zinc stearate, silane coupling agent, and modified polyethylene wax, significantly improving the dispersion uniformity of the TPU soft-gel masterbatch. DETAILED DESCRIPTION

[0029] The present application is further described in detail below with reference to preparation examples, embodiments and comparative examples.

[0030] Unless otherwise specified, the raw materials used in the preparation examples, embodiments and comparative examples of the present application are all commercially available.

[0031] TPU was purchased from BASF, Germany, TPU SP 9345 extrusion grade; The pigment is iron oxide red, purchased from Lingshou County Shifeng Mining Processing Plant, iron oxide red 130, specification 400mu; The additive is an antioxidant, purchased from BASF Irganox 245 antioxidant; The silane coupling agent was purchased from Si-550 silane coupling agent.

[0032] Preparation examples of raw materials and / or intermediates Preparation Example 1 A modified polyethylene wax is prepared by the following steps: S1. Place the polyethylene wax raw material in a stirring container, heat and melt it, then add maleic anhydride and an initiator, raise the temperature to 150° C. and react for 4 hours to obtain a crude modified polyethylene wax; S2. Dissolve the crude modified polyethylene wax obtained in step S1 in toluene at a ratio of 1 g:2 mL. After cooling, add acetone at a volume of 5 times that of toluene. Stir and filter the mixture. Wash with acetone and dry at 65° C. to obtain a finished modified polyethylene wax.

[0033] Note: In the above operation, the average molecular weight of the polyethylene wax raw material is 4000; the amount of maleic anhydride used is 8% of the mass of the polyethylene wax; the amount of initiator used is 0.2% of the mass of the polyethylene wax, and the initiator is benzoyl peroxide.

[0034] Preparation Example 2 A modified polyethylene wax is different from that of Preparation Example 1 in that the average molecular weight of the polyethylene wax raw material is 3000.

[0035] Preparation Example 3 A modified polyethylene wax is different from that of Preparation Example 1 in that the average molecular weight of the polyethylene wax raw material is 5000.

[0036] Preparation Example 4 A modified polyethylene wax is different from that of Preparation Example 1 in that the average molecular weight of the polyethylene wax raw material is 2500.

[0037] Preparation Example 5 A modified polyethylene wax is different from that of Preparation Example 1 in that the average molecular weight of the polyethylene wax raw material is 5500.

[0038] Example 1 A TPU soft rubber masterbatch, the raw materials used in its preparation and their corresponding weight parts are shown in Table 1, and it is prepared by the following steps: (1) Prepare raw materials including TPU, pigment, additive, zinc stearate, silane coupling agent and modified polyethylene wax according to the ratio; (2) After the TPU, pigment, additive, zinc stearate, silane coupling agent and modified polyethylene wax in step (1) are mixed and dispersed, the mixed material is added to a twin-screw extruder for melt extrusion, and pelletized after cooling and solidification to obtain TPU soft rubber masterbatch.

[0039] Note: In step (2), the melt extrusion temperature is 205°C. The modified polyethylene wax is obtained from Preparation Example 1.

[0040] Example 2-3 A TPU soft rubber masterbatch is different from Example 1 in that the raw materials used in its preparation and their corresponding weight parts are shown in Table 1.

[0041] Table 1 Raw materials used in the preparation of Examples 1-3 and their corresponding weight parts (parts / kg) raw material Example 1 Example 2 Example 3 TPU 60 50 70 pigment 27.5 25 30 additive 3 1 5 Zinc stearate 2 1 3 Silane coupling agent 1.25 0.5 2 Modified polyethylene wax 3.5 2 5

[0042] Example 4 A TPU soft rubber masterbatch is different from Example 1 in that the total weight of zinc stearate, silane coupling agent and modified polyethylene wax remains unchanged, and the weight ratio of the three is adjusted to 2:1:3.

[0043] Example 5 A TPU soft rubber masterbatch, which is different from Example 1 in that the modified polyethylene wax is obtained from Preparation Example 2.

[0044] Example 6 A TPU soft rubber masterbatch, which is different from Example 1 in that the modified polyethylene wax is obtained from Preparation Example 3.

[0045] Example 7 A TPU soft rubber masterbatch, which is different from Example 1 in that the modified polyethylene wax is obtained from Preparation Example 4.

[0046] Example 8 A TPU soft rubber masterbatch, which is different from Example 1 in that the modified polyethylene wax is obtained from Preparation Example 5.

[0047] Example 9 A TPU soft glue masterbatch, which is different from Example 1 in that, in step (2), the melt extrusion temperature is 190°C.

[0048] Example 10 A TPU soft glue masterbatch, which is different from Example 1 in that, in step (2), the melt extrusion temperature is 220°C.

[0049] Example 11 A TPU soft rubber masterbatch differs from Example 1 in that 5 parts by weight of a functional additive are further added to the raw materials of the TPU soft rubber masterbatch. The functional additive is composed of nano-montmorillonite and nano-barium sulfate in a weight ratio of 1.5:1, and the functional additive is mixed with the raw materials for addition. The particle size of the nano-montmorillonite and nano-barium sulfate is 40 nm.

[0050] Example 12 A TPU soft rubber masterbatch, which is different from Example 11 in that the weight portion of the functional additive added is 4 parts.

[0051] Example 13 A TPU soft rubber masterbatch, which is different from Example 11 in that the weight portion of the functional additive added is 6 parts.

[0052] Example 14 A TPU soft glue masterbatch, which is different from Example 11 in that the functional additive is composed of nano-montmorillonite and nano-barium sulfate in a weight ratio of 1.2:1.

[0053] Example 15 A TPU soft glue masterbatch, which is different from Example 11 in that the functional additive is composed of nano-montmorillonite and nano-barium sulfate in a weight ratio of 1.8:1.

[0054] Example 16 A TPU soft glue masterbatch, which is different from Example 11 in that the particle size of the nano-montmorillonite and the nano-barium sulfate is 30 nm.

[0055] Example 17 A TPU soft glue masterbatch, which is different from Example 11 in that the particle size of the nano-montmorillonite and the nano-barium sulfate is 50 nm.

[0056] Example 18 A TPU soft glue masterbatch, which is different from Example 11 in that nano-montmorillonite is not used in the preparation raw materials.

[0057] Example 19 A TPU soft rubber masterbatch, which differs from Example 11 in that nano-barium sulfate is not used in the preparation raw materials.

[0058] Comparative Example 1 A TPU soft rubber masterbatch is different from Example 1 in that zinc stearate and modified polyethylene wax are not used in the preparation raw materials.

[0059] Comparative Example 2 A TPU soft rubber masterbatch is different from Example 1 in that no silane coupling agent and modified polyethylene wax are used in the preparation raw materials.

[0060] Comparative Example 3 A TPU soft rubber masterbatch is different from Example 1 in that zinc stearate and silane coupling agent are not used in the preparation raw materials.

[0061] Comparative Example 4 A TPU soft rubber masterbatch is different from Example 1 in that zinc stearate is not used in the preparation raw materials.

[0062] Comparative Example 5 A TPU soft rubber masterbatch is different from Example 1 in that no silane coupling agent is used in the preparation of raw materials.

[0063] Comparative Example 6 A TPU soft rubber masterbatch is different from Example 1 in that modified polyethylene wax is not used in the preparation raw materials.

[0064] Comparative Example 7 A TPU soft rubber masterbatch is different from Example 1 in that zinc stearate, silane coupling agent and modified polyethylene wax are not used in the preparation raw materials.

[0065] Comparative Example 8 A TPU soft rubber masterbatch, which is different from Example 11 in that zinc stearate, silane coupling agent and modified polyethylene wax are not used in the preparation raw materials.

[0066] Comparative Example 9 A TPU soft rubber masterbatch, which is different from Example 1 in that the modified polyethylene wax is replaced by polyethylene wax raw material.

[0067] Performance testing Test samples: The TPU soft rubber masterbatch obtained in Examples 1-19 was selected as the test sample 1-19, and the TPU soft rubber masterbatch obtained in Comparative Examples 1-9 was selected as the control sample 1-9.

[0068] Test method: For masterbatch, its dispersion uniformity can be indirectly characterized and reflected by transmittance. Transmittance can reflect the hiding power. The greater the transmittance, the stronger the light transmittance and the lower the hiding power of the pigment. The smaller the transmittance, the better the hiding power of the pigment. For masterbatch, the dispersion level of the pigment is the main factor affecting the hiding power.

[0069] TPU soft glue masterbatch was added to TPU and injection molded at 195°C to obtain a thin sheet with a thickness of 2.5 mm. The pigment content in the sheet was 0.5%. The pigment iron oxide red used is red mainly due to its α-type crystal structure. This specific arrangement makes the compound selectively absorb the 500-600nm wavelength in the visible light. The transmittance of the sheet was tested at 500nm, 550nm, and 600nm respectively, and the average value was recorded as the transmittance value in the wavelength range of 500-600nm. The lower the transmittance value obtained, the higher the covering rate and the better the dispersion uniformity of the TPU soft glue masterbatch.

[0070] After the above tests were performed on the test samples 1-19 and the control samples 1-9, the test results were recorded in Table 2.

[0071] Table 2 Test results of test samples 1-19 and control samples 1-9 sample Transmittance value (%) Test sample 1 65.8 Test sample 2 67.2 Test sample 3 66.3 Test sample 4 64.2 Test sample 5 66.7 Test sample 6 66.5 Test sample 7 68.6 Test sample 8 68.8 Test sample 9 66.4 Test sample 10 67.0 Test sample 11 58.4 Test sample 12 58.9 Test sample 13 58.6 Test sample 14 58.7 Test sample 15 59.0 Test sample 16 58.8 Test sample 17 59.1 Test sample 18 62.7 Test sample 19 62.5 Control sample 1 72.8 Control sample 2 72.3 Control sample 3 72.6 Control sample 4 70.5 Control sample 5 70.0 Control sample 6 70.2 Control sample 7 74.9 Control sample 8 67.8 Control sample 9 69.3 Combining Example 1 with Comparative Examples 1-7 and Table 2, it can be seen that in the raw material system of TPU soft glue masterbatch, the combined use of zinc stearate, silane coupling agent, and modified polyethylene wax can significantly improve the dispersion uniformity of TPU soft glue masterbatch; if any one or two of zinc stearate, silane coupling agent, and modified polyethylene wax are used, although the dispersion uniformity can be improved, the improvement is limited, and any two raw materials can only play a simple additive effect. Only when the three are used together can a more significant compound synergistic effect be achieved. Combining Comparative Example 9 with Table 2, it can be seen that if the modified polyethylene wax is replaced with polyethylene wax raw material, the dispersion uniformity of the TPU soft glue masterbatch will be significantly reduced. Therefore, it can be seen that polyethylene wax raw material cannot form a good combination effect with zinc stearate and silane coupling agent.

[0072] Combining Examples 1-3 and Example 4 with Table 2, it can be seen that when the weight ratio of zinc stearate, silane coupling agent and modified polyethylene wax is 2:1:3, the three have better corresponding effects in the TPU soft glue masterbatch, and the transmittance value obtained by the above test is low, indicating that the dispersion uniformity of the TPU soft glue masterbatch is better.

[0073] Combining Examples 1 and 5-8 with Table 2, it can be seen that in the preparation of modified polyethylene wax, controlling the average molecular weight of the polyethylene wax raw material to 3000-5000 ensures that the modified polyethylene wax forms an optimal coordination system with zinc stearate and the silane coupling agent, thereby achieving excellent results and ultimately producing TPU soft-gel masterbatches with excellent dispersion uniformity. However, when the average molecular weight of the polyethylene wax raw material is below or above the above range, the dispersion uniformity of the TPU soft-gel masterbatches obtained using the modified polyethylene wax is significantly reduced, indicating that the average molecular weight of the polyethylene wax raw material is particularly important for the application effect of the modified polyethylene wax.

[0074] From Example 1 and Examples 9-10 and Table 2, it can be seen that the selection of a melt extrusion temperature of 190-220°C during the preparation can ensure complete melting of the material and obtain a stable dispersion effect, thereby obtaining a TPU soft rubber masterbatch with excellent and stable quality.

[0075] Combining Example 1 with Examples 11-15 and Table 2, it can be seen that by adding a functional additive composed of nano-montmorillonite and nano-barium sulfate, the transmittance value of the obtained TPU soft glue masterbatch obtained by the above test can be further reduced, indicating that the dispersion uniformity of the TPU soft glue masterbatch is significantly improved. Combining Examples 16-17 and Table 2, it can be seen that the particle size of nano-montmorillonite and nano-barium sulfate is 30-50nm, which can enable the functional additive to exert a stable and better corresponding effect after application. Combining Examples 18-19 and Table 2, it can be seen that if nano-montmorillonite or nano-barium sulfate is added alone, although it can bring about a corresponding effect, the improvement is limited, and the sum of the improvement effects brought by the use of each alone is far less than the excellent effect brought by the combination of the two. Therefore, it can be seen that the combination of nano-montmorillonite and nano-barium sulfate can bring about a significant improvement effect of 1+1>2. Combined with Comparative Examples 7-8 and Table 2, it can be seen that if the TPU soft rubber masterbatch lacks the coordination system formed by modified polyethylene wax, zinc stearate and silane coupling agent, the corresponding improvement effect brought by the functional additive will be significantly discounted. This shows that the functional additive can synergistically enhance the coordination system formed by zinc stearate, silane coupling agent and modified polyethylene wax, thereby significantly improving the dispersion uniformity of the TPU soft rubber masterbatch.

[0076] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed, but as long as they are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A TPU soft glue masterbatch, characterized in that: Made from the following raw materials in parts by weight: TPU 50-70 parts; Pigment 25-50 parts; 1-5 parts of additives; 1-3 parts of zinc stearate; Silane coupling agent 0.5-2 parts; 2-5 parts of modified polyethylene wax; The modified polyethylene wax is prepared by the following steps: S1. Place the polyethylene wax raw material in a stirring container, heat and melt it, then add maleic anhydride and an initiator, and heat the reaction to obtain a crude modified polyethylene wax; S2. Add toluene to dissolve the crude modified polyethylene wax obtained in step S1, add acetone after cooling, stir, filter, wash, and dry to obtain a finished modified polyethylene wax.

2. The TPU soft glue masterbatch according to claim 1, characterized in that: The weight ratio of the zinc stearate, the silane coupling agent and the modified polyethylene wax is 2:1:

3.

3. The TPU soft glue masterbatch according to claim 1, characterized in that: In the preparation of the modified polyethylene wax, the average molecular weight of the polyethylene wax raw material is 3000-5000.

4. The TPU soft glue masterbatch according to claim 1, characterized in that: The raw materials of the TPU soft glue masterbatch are further added with 4-6 parts by weight of a functional additive, wherein the functional additive is composed of nano-montmorillonite and nano-barium sulfate, and the weight ratio of the nano-montmorillonite to the nano-barium sulfate is (1.2-1.8):

1.

5. The TPU soft glue masterbatch according to claim 4, characterized in that: The weight ratio of the nano-montmorillonite to the nano-barium sulfate is 1.5:

1.

6. The TPU soft glue masterbatch according to claim 4, characterized in that: The particle size of the nano-montmorillonite and nano-barium sulfate is 30-50 nm.

7. The TPU soft glue masterbatch according to claim 1, characterized in that: The pigment is one or a combination of titanium dioxide, carbon black, cadmium red, cadmium yellow, titanium dioxide, red iron oxide and yellow iron oxide.

8. The TPU soft glue masterbatch according to claim 1, characterized in that: The additive is one or a combination of stabilizers, antioxidants, flame retardants, antistatic agents and slip agents.

9. The method for preparing the TPU soft glue masterbatch according to claim 1, characterized in that: The following steps are involved: (1) Prepare raw materials including TPU, pigment, additive, zinc stearate, silane coupling agent and modified polyethylene wax according to the ratio; (2) After the TPU, pigment, additive, zinc stearate, silane coupling agent and modified polyethylene wax in step (1) are mixed and dispersed, the mixed material is added to a twin-screw extruder for melt extrusion, and pelletized after cooling and solidification to obtain TPU soft rubber masterbatch.

10. The method for preparing TPU soft glue masterbatch according to claim 9, characterized in that: In step (2), the melt extrusion temperature is 190-220°C.