Super-hydrophilic cool granule and preparation method and application thereof

Abstract

The application belongs to the technical field of high polymer materials, and particularly relates to a super-hydrophilic cool master batch and a preparation method and application thereof. The super-hydrophilic cool master batch is prepared by pre-dispersing the hydrophilic modifier to firmly coat the surface of the heat-conducting filler, and further combining the bridging action of the subsequent maleic anhydride grafted polyolefin, so as to effectively solve the compatibility problem of the inorganic filler and the polyolefin, and simultaneously give the master batch the persistent super-hydrophilic property and the high-efficiency heat-conducting capacity, and solve the defect that the hydrophilic-heat-dissipation function of the traditional material is difficult to be compatible. Gradient temperature control and special screw design are adopted to protect the heat-sensitive components and realize uniform dispersion of the filler. The subsequent rapid water cooling process locks the surface hydrophilic function of the master batch, and avoids migration failure. The super-hydrophilic cool master batch obtained by the application has the persistent super-hydrophilic property and the high-efficiency heat-conducting capacity.

Description

Technical Field

[0001] This invention belongs to the field of polymer materials technology, specifically relating to a superhydrophilic cooling masterbatch, its preparation method, and its application. Background Technology

[0002] Cooling masterbatches are key materials for imparting heat dissipation to synthetic fibers, but current mainstream technologies have significant limitations. Thermally conductive masterbatches rely on large amounts of metal oxide fillers to enhance thermal conductivity, but high addition levels lead to difficulties in spinning, frequent fiber breakage, and a significant decrease in thermal conductivity after washing. Hydrophilic modified masterbatches use surfactants to achieve moisture absorption and wicking, but small-molecule auxiliaries easily migrate and precipitate, causing a sharp decrease in hydrophilicity after several washes, or even complete loss of function. Phase change material masterbatches provide a cooling sensation through microencapsulation phase change heat absorption; however, the capsule structure is easily damaged during spinning, has poor wash resistance, and suffers severe performance degradation with long-term use.

[0003] Existing improvement solutions attempt to combine multiple functional materials (such as graphene with hydrophilic resins), but face problems such as high dispersion costs of nanomaterials and complex processes, and still cannot effectively solve the stuffiness caused by sweat retention. The industry has long lacked a solution that can achieve a balance between processing applicability, hydrophilic durability, and heat dissipation efficiency, which has hindered the development of high-performance cooling textiles. Summary of the Invention

[0004] The purpose of this invention is to provide a superhydrophilic cooling masterbatch, its preparation method, and its application. Compared with the cooling masterbatch in the prior art, the superhydrophilic cooling masterbatch obtained by the method provided by this invention has stronger hydrophilicity, thereby improving its adaptability, and also has more significant cooling and drying properties.

[0005] To achieve the above objectives, the present invention provides the following technical solution: This invention provides a method for preparing a superhydrophilic cooling masterbatch, comprising the following steps: A thermally conductive filler, a dispersant, and a hydrophilic modifier are first mixed to obtain a pre-dispersed filler; the hydrophilic modifier includes at least one of polyethylene glycol and polyvinylpyrrolidone. The pre-dispersed filler, polyolefin, maleic anhydride-grafted polyolefin and antioxidant are mixed and then extruded and water-cooled pelletized in sequence to obtain the superhydrophilic cool masterbatch.

[0006] Preferably, the thermally conductive filler comprises at least one of boron nitride nanosheets and modified alumina; The modified alumina is KH550 modified alumina.

[0007] Preferably, the dispersant comprises at least one of zinc stearate and γ-aminopropyltriethoxysilane; The antioxidant includes tris(2,4-di-tert-butylphenyl) phosphite.

[0008] Preferably, the polyolefin includes at least one of polyethylene and polypropylene; When the polyolefin is polypropylene, the maleic anhydride-grafted polyolefin is maleic anhydride-grafted polypropylene; when the polyolefin is polyethylene, the maleic anhydride-grafted polyolefin is maleic anhydride-grafted polyethylene.

[0009] Preferably, the raw materials for preparing the superhydrophilic cooling masterbatch, by mass parts, include: 50-80 parts of polyolefin, 10-30 parts of hydrophilic modifier, 5-25 parts of thermally conductive filler, 1-5 parts of dispersant, 2-8 parts of maleic anhydride-grafted polyolefin, and 0.1-1 parts of antioxidant.

[0010] Preferably, the first mixing is carried out under stirring conditions, wherein the stirring speed is 800~1500 rpm and the time is 5~15 min; The first mixing is carried out under a protective atmosphere at a temperature of 40~60°C.

[0011] Preferably, the extrusion temperature is 180~230℃, the screw speed is 200~400rpm, and the melt pressure is 2~8MPa.

[0012] Preferably, the cooling water temperature for the water-cooled pellets is 10~25℃, and the contact time between the extruded material and the water is ≤10s.

[0013] The present invention also provides a superhydrophilic cooling masterbatch prepared by the preparation method described in the above technical solution.

[0014] The present invention also provides the application of the superhydrophilic cooling masterbatch described above in textiles and building materials.

[0015] Compared with the prior art, the beneficial effects of the present invention include: (1) By pre-dispersing the thermally conductive filler, dispersant and hydrophilic modifier, the hydrophilic modifier firmly coats the surface of the thermally conductive filler. This, combined with the bridging effect of the subsequent maleic anhydride-grafted polyolefin (as an interface compatibilizer), effectively solves the compatibility problem between inorganic filler and polyolefin. Simultaneously, it endows the masterbatch with long-lasting superhydrophilicity and high-efficiency thermal conductivity, solving the defect that the hydrophilic-heat dissipation function of traditional materials is difficult to be compatible. (2) During the extrusion process, both heat-sensitive components are protected and filler is uniformly dispersed; the subsequent rapid water cooling process locks in the hydrophilic function of the masterbatch surface, avoiding migration failure and high-temperature degradation; the pre-dispersion step reduces screw wear, significantly reduces energy consumption and raw material residue, and the production process is greener and more controllable. (3) The superhydrophilic cooling masterbatch obtained by the present invention has both long-lasting superhydrophilicity and high thermal conductivity. It accelerates sweat diffusion and reduces body temperature in textiles, enhances heat dissipation efficiency in building materials, and maintains functional stability after multiple washes or long-term use. At the same time, it reduces production energy consumption and equipment wear, meets the long-term cooling needs of multiple fields, and is suitable for the large-scale manufacturing of multifunctional composite materials. Detailed Implementation

[0016] This invention provides a method for preparing a superhydrophilic cooling masterbatch, comprising the following steps: A thermally conductive filler, a dispersant, and a hydrophilic modifier are first mixed to obtain a pre-dispersed filler; the hydrophilic modifier includes at least one of polyethylene glycol and polyvinylpyrrolidone. The pre-dispersed filler, polyolefin, maleic anhydride-grafted polyolefin and antioxidant are mixed and then extruded and water-cooled pelletized in sequence to obtain the superhydrophilic cool masterbatch.

[0017] The present invention first mixes thermally conductive filler, dispersant and hydrophilic modifier to obtain pre-dispersed filler; the hydrophilic modifier includes at least one of polyethylene glycol and polyvinylpyrrolidone.

[0018] In this invention, the raw materials for preparing the superhydrophilic cooling masterbatch preferably include, by mass parts: 50-80 parts of polyolefin, 10-30 parts of hydrophilic modifier, 5-25 parts of thermally conductive filler, 1-5 parts of dispersant, 2-8 parts of maleic anhydride-grafted polyolefin, and 0.1-1 parts of antioxidant.

[0019] The raw materials for preparing the superhydrophilic cooling masterbatch provided by the present invention, by weight, include 50 to 80 parts of polyolefin, more preferably 50, 60, 70, or 80 parts; the polyolefin preferably includes at least one of polyethylene and polypropylene.

[0020] Based on the mass fraction of the polyolefin, the raw materials for preparing the superhydrophilic cooling masterbatch provided by the present invention include 10 to 30 parts of a hydrophilic modifier, more preferably 10, 12, 15, 20, 25, 28, or 30 parts; the hydrophilic modifier includes at least one of polyethylene glycol and polyvinylpyrrolidone.

[0021] Based on the mass fraction of the polyolefin, the raw materials for preparing the superhydrophilic cooling masterbatch provided by the present invention include 5 to 25 parts of thermally conductive filler, more preferably 5 parts, 8 parts, 10 parts, 15 parts, 20 parts, 22 parts, or 25 parts; the thermally conductive filler preferably includes at least one of boron nitride nanosheets and modified alumina; the modified alumina is preferably KH550 modified alumina.

[0022] Based on the mass fraction of the polyolefin, the raw materials for preparing the superhydrophilic cooling masterbatch provided by the present invention include 1 to 5 parts of dispersant, more preferably 1 part, 1.5 parts, 2 parts, 3 parts, 4 parts, or 5 parts; the dispersant preferably includes at least one of zinc stearate and γ-aminopropyltriethoxysilane.

[0023] Based on the mass fraction of the polyolefin, the raw materials for preparing the superhydrophilic cooling masterbatch provided by the present invention include 2 to 8 parts of maleic anhydride-grafted polyolefin, more preferably 2, 3, 4, 5, 6, 7, or 8 parts. In the present invention, when the polyolefin is polypropylene, the maleic anhydride-grafted polyolefin is preferably maleic anhydride-grafted polypropylene; when the polyolefin is polyethylene, the maleic anhydride-grafted polyolefin is preferably maleic anhydride-grafted polyethylene.

[0024] Based on the mass fraction of the polyolefin, the raw materials for preparing the superhydrophilic cooling masterbatch provided by the present invention include 0.1 to 1 part of antioxidant, specifically 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1 part; the antioxidant preferably includes tris(2,4-di-tert-butylphenyl) phosphite.

[0025] Before the first mixing, the present invention preferably dries the thermally conductive filler, wherein the drying temperature is preferably 100~120℃, the drying time is preferably 2~4h, and the moisture content of the thermally conductive filler is controlled to be ≤0.5%.

[0026] In this invention, the first mixing is preferably carried out under stirring conditions, the stirring speed is preferably 800~1500 rpm, specifically 800 rpm, 900 rpm, 1000 rpm, 1100 rpm, 1200 rpm, 1300 rpm, 1400 rpm, or 1500 rpm; the time is preferably 5~15 min, specifically 5 min, 10 min, or 15 min; the first mixing is preferably carried out under a protective atmosphere, the protective atmosphere is preferably an inert atmosphere, more preferably argon; the temperature is preferably 40~60℃, more preferably 50℃.

[0027] After obtaining the pre-dispersed filler, the present invention mixes the pre-dispersed filler, polyolefin, maleic anhydride-grafted polyolefin and antioxidant, and then performs extrusion and water-cooled pelletizing in sequence to obtain the superhydrophilic cool masterbatch.

[0028] In this invention, before the second mixing, it is preferable to further dry the polyolefin and the maleic anhydride-grafted polyolefin separately, wherein the drying temperature is preferably 80°C and the drying time is preferably 1 to 2 hours.

[0029] In this invention, the extrusion is performed using a twin-screw extruder. The extrusion temperature is preferably 180~230℃, specifically 180℃, 190℃, 200℃, 210℃, 220℃, or 230℃; the screw speed is preferably 200~400 rpm, more preferably 300 rpm; and the melt pressure is preferably 2~8 MPa, more preferably 2 MPa, 3 MPa, 4 MPa, 5 MPa, 6 MPa, 7 MPa, or 8 MPa.

[0030] In this invention, the cooling water temperature for the water-cooled pellets is preferably 10~25℃, and the contact time between the extruded material and water is preferably ≤10s. In this invention, after extrusion, drying is also preferably performed; the drying process is preferably: drying in a vacuum drying oven at 50~70℃ until the moisture content is ≤0.1%.

[0031] In this invention, the superhydrophilic cooling masterbatch is preferably cylindrical, with a diameter of 2-4 mm and a length of 3-4 mm.

[0032] The present invention also provides a superhydrophilic cooling masterbatch prepared by the preparation method described in the above technical solution.

[0033] The present invention also provides the application of the superhydrophilic cooling masterbatch described above in textiles and building materials.

[0034] Unless otherwise specified, the materials and equipment used in this invention are all commercially available products in the field.

[0035] The technical solutions of this invention will be clearly and completely described below with reference to the embodiments thereof. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0036] Examples 1-6 The formulations for Examples 1-6 are shown in Table 1; Table 1. Formulations (in portions) for Examples 1-6

[0037] Among them, polypropylene is selected as the polyolefin, polyethylene glycol is selected as the hydrophilic modifier, boron nitride nanosheets are selected as the thermally conductive filler, zinc stearate is selected as the dispersant, and tris(2,4-di-tert-butylphenyl) phosphite (CAS No.: 31570-04-4) is selected as the antioxidant. The preparation method is as follows: The thermally conductive filler was dried at 115℃ for 3 hours (with the moisture content controlled to be ≤0.5%), and the polypropylene and maleic anhydride-grafted polypropylene were dried at 80℃ for 2 hours. The dried thermally conductive filler, dispersant, and hydrophilic modifier were added to a high-speed mixer and mixed at 1100 rpm for 10 minutes under an argon atmosphere, with the temperature controlled at 55°C, to form a pre-dispersed filler. Polypropylene, maleic anhydride-grafted polypropylene, and antioxidants were added to the pre-dispersed filler. The mixture was melt-blended and extruded in a twin-screw extruder, with the extrusion temperature controlled at 200℃, the screw speed at 300rpm, and the melt pressure at 6MPa. The blended melt was then extruded through a die, water-cooled, and pelletized. The cooling water temperature was 15℃ (the contact time between the extruded material and the cooling water did not exceed 10s), resulting in cylindrical particles with a diameter of 2-4mm and a length of 3-4mm. The particles were then dried in a vacuum drying oven at 60℃ for 10min until the moisture content was ≤0.1%, thus obtaining the superhydrophilic cool masterbatch.

[0038] Comparative Example 1 Compared with Example 1, Comparative Example 1 blended all raw materials, and the component ratios were the same as those in Example 1; The preparation method involves the following steps: (1) Dry the thermally conductive filler at 100~120℃ for 3 hours, and dry the polypropylene and maleic anhydride-grafted polypropylene at 80℃ for 2 hours. (2) Add the thermally conductive filler, dispersant, hydrophilic modifier, polypropylene, maleic anhydride-grafted polypropylene and antioxidant into a high-speed mixer and mix at 1100 rpm for 10 min, with the temperature controlled at 55℃, to obtain the mixture. (3) The mixture is melt-blended in a twin-screw extruder, with the extrusion temperature controlled at 200℃, the screw speed at 300rpm, and the melt pressure at 6MPa. The blended melt is extruded through a die, water-cooled and pelletized, with the cooling water temperature at 15℃, to obtain cylindrical particles with a diameter of 2~4mm and a length of 3~4mm. The particles are then dried in a vacuum drying oven at 60℃ for 10 minutes to obtain the masterbatch.

[0039] Comparative Example 2 Compared with Example 1, Comparative Example 2 did not add maleic anhydride-grafted polypropylene, and the proportions of the remaining components were the same as in Example 1.

[0040] Performance testing Test Example 1 The hydrophilicity of the masterbatches obtained in the examples and comparative examples was tested, and the results are shown in Table 2. Table 2. Hydrophilicity of the masterbatches obtained in the examples and comparative examples

[0041] Test Example 2 The thermal conductivity of the masterbatches obtained in the examples and comparative examples was tested, and the results are shown in Table 3. Table 3 Thermal conductivity of the masterbatches obtained in the examples and comparative examples

[0042] As shown in Tables 2 and 3, the superhydrophilic cooling masterbatch prepared by this invention is superior to the comparative examples in both hydrophilicity and thermal conductivity. Examples 1-6 all achieved instantaneous spreading of water droplets on the masterbatch surface, and the wettability did not decrease after repeated washing. In contrast, the hydrophilic modifier and filler agglomerated due to the one-step mixing process in Comparative Example 1, resulting in hydrophobic spots on the masterbatch. In Comparative Example 2, the filler gradually detached from the matrix due to the lack of the compatibilizer maleic anhydride-grafted polyolefin, leading to a continuous deterioration in hydrophilicity. Regarding thermal conductivity, the boron nitride nanosheets in the examples formed a uniform heat dissipation network, resulting in rapid heat transfer without localized heat accumulation. In contrast, the agglomerates in Comparative Example 1 blocked the heat conduction path, and the interface debonding in Comparative Example 2 caused a sharp drop in heat dissipation efficiency.

[0043] Although the above embodiments have provided a detailed description of the present invention, they are only some embodiments of the present invention, and not all embodiments. Other embodiments can be obtained based on these embodiments without creative effort, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A method for preparing a superhydrophilic cooling masterbatch, characterized in that, Includes the following steps: A thermally conductive filler, a dispersant, and a hydrophilic modifier are first mixed to obtain a pre-dispersed filler; the hydrophilic modifier includes at least one of polyethylene glycol and polyvinylpyrrolidone. The pre-dispersed filler, polyolefin, maleic anhydride-grafted polyolefin and antioxidant are mixed and then extruded and water-cooled pelletized in sequence to obtain the superhydrophilic cool masterbatch.

2. The preparation method according to claim 1, characterized in that, The thermally conductive filler includes at least one of boron nitride nanosheets and modified alumina; the modified alumina is KH550 modified alumina.

3. The preparation method according to claim 1, characterized in that, The dispersant includes at least one of zinc stearate and γ-aminopropyltriethoxysilane; The antioxidant includes tris(2,4-di-tert-butylphenyl) phosphite.

4. The preparation method according to claim 1, characterized in that, The polyolefin includes at least one of polyethylene and polypropylene; When the polyolefin is polypropylene, the maleic anhydride-grafted polyolefin is maleic anhydride-grafted polypropylene; when the polyolefin is polyethylene, the maleic anhydride-grafted polyolefin is maleic anhydride-grafted polyethylene.

5. The preparation method according to any one of claims 1 to 4, characterized in that, The raw materials for preparing the superhydrophilic cooling masterbatch, by mass parts, include: 50-80 parts of polyolefin, 10-30 parts of hydrophilic modifier, 5-25 parts of thermally conductive filler, 1-5 parts of dispersant, 2-8 parts of maleic anhydride-grafted polyolefin, and 0.1-1 parts of antioxidant.

6. The preparation method according to claim 1, characterized in that, The first mixing is carried out under stirring conditions, wherein the stirring speed is 800~1500 rpm and the time is 5~15 min; The first mixing is carried out under a protective atmosphere at a temperature of 40~60°C.

7. The preparation method according to claim 1, characterized in that, The extrusion temperature is 180~230℃, the screw speed is 200~400rpm, and the melt pressure is 2~8MPa.

8. The preparation method according to claim 1, characterized in that, The cooling water temperature for the water-cooled pellets is 10~25℃, and the contact time between the extruded material and the water is ≤10s.

9. The superhydrophilic cooling masterbatch prepared by the preparation method according to any one of claims 1 to 8.

10. The application of the superhydrophilic cooling masterbatch of claim 9 in textiles and building materials.

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