Activation treatment-free high-performance melt-blown elastic material and preparation method thereof

Abstract

The invention relates to the technical field of non-woven fabrics, in particular to a high-performance melt-blown elastic material without activation treatment and a preparation method of the high-performance melt-blown elastic material. The melt-blown elastic material comprises the following raw materials: master batch and a second polyolefin elastomer; the mass ratio of the master batch to the second polyolefin elastomer is 1: (1-7); the master batch comprises the following raw materials in percentage by weight: 4-50% of polypropylene; 40%-85% of a first polyolefin elastomer; and 5%-20% of erucyl amide. Through innovative material formula design and process parameter optimization, the elastic balance and high recovery rate of the elastic material in the MD and CD directions are remarkably improved, and the limitation of the prior art is overcome. Specifically, the melt-blown elastic material disclosed by the invention can still reach a high-performance index that the recovery rate is greater than or equal to 85% under the condition that activation treatment is not needed.

Description

Technical Field

[0001] The invention relates to the technical field of nonwoven fabrics, and in particular to a melt-blown elastic material having multi-directional balanced elasticity and requiring no stimulating treatment, and a preparation method thereof. Background Art

[0002] In the fields of personal hygiene care and medical protection, elastic nonwovens are favored for their good fit and comfort. However, in the prior art, meltblown materials with high elastic properties usually require complex composite methods or activating processes, which not only increases production costs and difficulty, but also limits large-scale industrial production. In addition, elastic nonwovens have poor elastic balance in the longitudinal (MD) and transverse (CD) directions, which affects their performance in practical applications.

[0003] Traditional technical solutions cannot achieve high elastic performance and elastic balance in MD and CD directions without excitation treatment. Therefore, a new material formula and preparation method are urgently needed to overcome the above technical difficulties, simplify the process and improve production efficiency. Summary of the invention

[0004] In view of the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a melt-blown elastic material and a preparation method thereof that does not require an irradiation treatment, has a simple process, has excellent multi-directional elasticity and high resilience. The present invention achieves a significant improvement in the elastic balance and high resilience of the elastic material in the MD and CD directions through innovative material formula design and process parameter optimization, overcoming the limitations of the prior art.

[0005] To achieve the above-mentioned object and other related objects, the present invention provides a high-performance melt-blown elastic material that does not require an energizing treatment. The raw materials of the melt-blown elastic material include a masterbatch and a second polyolefin elastomer; the mass ratio of the masterbatch to the second polyolefin elastomer is 1:(1-7);

[0006] The raw materials of masterbatch include by weight percentage:

[0007] Polypropylene 4% to 50%;

[0008] 40% to 85% of the first polyolefin elastomer;

[0009] Erucamide 5%~20%.

[0010] In some embodiments of the present invention, the melt flow index of the polypropylene is 100 to 1800 g / 10 min.

[0011] In some embodiments of the present invention, the first polyolefin elastomer is Vistamaxx 7050FL.

[0012] In some embodiments of the present invention, the second polyolefin elastomer is Vistamaxx 7050FL.

[0013] In some embodiments of the present invention, the raw material of the meltblown elastic material further includes a functional additive, and the functional additive is selected from an antioxidant or an anti-ultraviolet additive.

[0014] A second aspect of the present invention provides a method for preparing a high-performance melt-blown elastic material without the need for an energizing treatment, the method comprising the following steps:

[0015] 1) Preparation of masterbatch: polypropylene, the first polyolefin elastomer and erucic acid amide are mixed, and mixed in a high-speed mixer at a speed of ≥1000 rpm for ≥5 minutes to form a uniform mixture; melt extruded, stretched, pelletized and dried at a temperature of ≤190° C. by a twin-screw extruder with a length-to-diameter ratio of ≥40:1 to prepare a masterbatch;

[0016] 2) Fiber web forming: the masterbatch is mixed with the second polyolefin elastomer, and melted in an extruder at ≤250°C to form a uniform melt; the melt is filtered and metered, and then extruded through a melt-blown die head with a pore size of 0.15 to 0.3 mm; the fiber is stretched by hot air flow and cooled by side blowing, and the fiber diameter is controlled to be 2 to 20 μm to form a fiber web;

[0017] 3) Finished product processing: the fiber web is cut and rolled up to produce a meltblown elastic material.

[0018] In some embodiments of the present invention, in step 2), the melting is carried out in an extruder, and the melting temperature is 240-250°C.

[0019] In some embodiments of the present invention, in step 2), the meltblowing die head has 1000 to 2000 holes / m.

[0020] In some embodiments of the present invention, in step 2), the temperature of the hot air flow is 200-270° C., and the wind speed is 0.5-3 m / s.

[0021] The present invention also provides a high-performance melt-blown elastic material that does not require energization treatment, which is prepared by the method described in the second aspect of the present invention. The elastic difference between the MD and CD directions of the melt-blown elastic material is ≤10%, and the recovery rate is ≥85%.

[0022] The present invention also provides an application of the high-performance melt-blown elastic material that does not require activating treatment as described above in the present invention in the field of personal hygiene care and medical protection.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] The present invention provides a high-performance melt-blown elastic material that does not require an activation treatment and a preparation method thereof. Through an innovative material formula, high-fluidity polypropylene, a specific polyolefin elastomer and a high content of erucic acid amide are combined in a specific proportion, combined with optimized melt-blown process parameters, to prepare a melt-blown elastic material with multi-directional balanced elasticity and high recovery rate. The melt-blown elastic material of the present invention has an elastic difference of ≤10% between the MD and CD directions and a recovery rate of ≥85% without the need for an activation treatment. It is significantly superior to the prior art level. The method simplifies the production process, reduces costs, and has broad application prospects. DETAILED DESCRIPTION

[0025] "Scope" disclosed in the present application is limited in the form of lower limit and upper limit, and a given range is limited by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundary of a special range. The scope limited in this way can be including end values ​​or not including end values, and can be arbitrarily combined, that is, any lower limit can be combined with any upper limit to form a scope. For example, if the scope of 60-120 and 80-110 is listed for a specific parameter, it is understood that the scope of 60-110 and 80-120 is also expected. In addition, if the minimum range values ​​1 and 2 are listed, and if the maximum range values ​​3, 4 and 5 are listed, the following scope can be all expected: 1-3, 1-4, 1-5, 2-3, 2-4 and 2-5. In the present application, unless otherwise specified, the numerical range "ab" represents the abbreviation of any real number combination between a and b, wherein a and b are real numbers. For example, the numerical range "0-5" means that all real numbers between "0-5" are listed in this document, and "0-5" is just an abbreviation of these numerical combinations. In addition, when a parameter is expressed as an integer ≥ 2, it is equivalent to disclosing that the parameter is, for example, an integer of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0026] If there is no special explanation, all steps of the present application can be performed sequentially or randomly, preferably sequentially. For example, the method includes steps 1) and 2), which means that the method may include steps 1) and 2) performed sequentially, or may include steps 2) and 1) performed sequentially.

[0027] Traditionally, high-performance meltblown elastic materials must be treated with activation. This invention breaks through this technical prejudice and, through innovative material formulation and process optimization, achieves excellent multi-directional elastic properties without activation treatment, significantly simplifies the production process, reduces production costs, and has a wide range of industrial application value.

[0028] Specifically, the present invention produces a non-obvious synergistic effect through the combination of polypropylene, polyolefin elastomer and high content of lubricant in a specific ratio. The addition of high content of erucamide not only plays a lubricating role, but also forms a microphase separation structure inside the material, promotes the orientation and crystallization of polymer chains, and significantly improves the elastic properties and recovery rate of the material.

[0029] By precisely controlling the component ratio and fiber molding conditions, the elasticity difference of the material in the MD and CD directions is controlled to ≤10%, which solves the technical problem of elastic imbalance in the prior art and improves the comfort and functionality of the product in practical applications.

[0030] In addition, the present invention has determined the optimal range of key process parameters such as high mixer speed, extrusion temperature, meltblowing die aperture and number of holes through a large number of experiments. The innovative selection of these parameters has a profound impact on the microstructure and macroscopic properties of the material, which can be directly deduced or foreseen by non-technical personnel based on the prior art.

[0031] In summary, the material can still achieve a high performance index of a recovery rate ≥ 85% without the need for an excitation treatment. This performance exceeds the expectations of the prior art, is an unexpected technical effect, and reflects the creativity of the present invention. On this basis, this application is completed.

[0032] [High-performance melt-blown elastic material without radiative treatment]

[0033] The first aspect of the present invention provides a high-performance melt-blown elastic material that does not require an energizing treatment, wherein the raw materials of the melt-blown elastic material include a masterbatch and a second polyolefin elastomer; the mass ratio of the masterbatch to the second polyolefin elastomer is 1:(1-7);

[0034] The raw materials of masterbatch include by weight percentage:

[0035] Polypropylene 4% to 50%;

[0036] 40% to 85% of the first polyolefin elastomer;

[0037] Erucamide 5%~20%.

[0038] In the high-performance melt-blown elastic material without the need for activating treatment provided by the present invention, the weight percentage of polypropylene in the masterbatch can be, for example, 4% to 4.75%, 4.75% to 42%, or 42% to 50%. The polypropylene is selected from high-flowability melt-blown fiber-grade polypropylene with a melt flow index of 100 to 1800 g / 10min to provide the material with mechanical strength and fiber formability. The melt flow index of the polypropylene can be, for example, 100 to 500 g / 10min, 500 to 1000 g / 10min, or 1000 to 1800 g / 10min.

[0039] In the high-performance melt-blown elastic material without the need for activating treatment provided by the present invention, the weight percentage of the first polyolefin elastomer in the masterbatch can be, for example, 40% to 42%, 42% to 82.75%, or 82.75% to 85%. The first polyolefin elastomer preferably uses a polyolefin elastomer of a specific grade (such as Vistamaxx 7050FL) to give the material excellent elasticity and flexibility.

[0040] In the high-performance melt-blown elastic material without the need for activating treatment provided by the present invention, the weight percentage of erucamide in the masterbatch can be, for example, 5% to 12.5%, 12.5% ​​to 16%, or 16% to 20%. The present invention innovatively adds a high proportion of erucamide, which not only improves the spinnability and surface smoothness of the fiber, but also forms a microphase separation structure in the polymer matrix, promotes the orientation and crystallization of the polymer chain, and improves the elastic properties of the material.

[0041] In the high-performance melt-blown elastic material provided by the present invention that does not require an activating treatment, a functional additive is added as needed, such as an antioxidant or an anti-ultraviolet additive, to enhance the weather resistance and environmental adaptability of the material. Optionally, the weight percentage of the functional additive in the masterbatch is 0.1% to 5%. Further optionally, the weight percentage of the functional additive in the masterbatch is 0.1% to 1%, 1% to 3%, or 3% to 5%.

[0042] In the high-performance melt-blown elastic material without activation treatment provided by the present invention, the mass ratio of the masterbatch to the second polyolefin elastomer is 1:(1-7). Optionally, the mass ratio of the masterbatch to the second polyolefin elastomer can be, for example, 1:(1-3), 1:(3-5) or 1:(5-7).

[0043] In the high-performance melt-blown elastic material provided by the present invention that does not require activating treatment, the second polyolefin elastomer preferably uses a polyolefin elastomer of a specific grade (such as Vistamaxx 7050FL) to give the material excellent elasticity and flexibility.

[0044] [Preparation method of high-performance melt-blown elastic material without activating treatment]

[0045] The second aspect of the present invention provides a method for preparing a high-performance melt-blown elastic material without the need for an energizing treatment, comprising the following steps:

[0046] 1) Preparation of masterbatch: polypropylene, the first polyolefin elastomer and erucic acid amide are mixed, and mixed in a high-speed mixer at a speed of ≥1000 rpm for ≥5 minutes to form a uniform mixture; melt extruded, stretched, pelletized and dried at a temperature of ≤190° C. by a twin-screw extruder with a length-to-diameter ratio of ≥40:1 to prepare a masterbatch;

[0047] 2) Fiber web forming: the masterbatch is mixed with the second polyolefin elastomer, and melted in an extruder at ≤250°C to form a uniform melt; the melt is filtered and metered, and then extruded through a melt-blown die head with a pore size of 0.15 to 0.3 mm; the fiber is stretched by hot air flow and cooled by side blowing, and the fiber diameter is controlled to be 2 to 20 μm to form a fiber web;

[0048] 3) Finished product processing: the fiber web is cut and rolled up to produce a meltblown elastic material.

[0049] In the preparation method of the high-performance melt-blown elastic material without the need for activating treatment provided by the present invention, step 1) is to mix polypropylene, a first polyolefin elastomer, and erucic acid amide to form a uniform mixture; melt extrusion, drawing, pelletizing and drying to prepare a masterbatch.

[0050] In step 1) of the present invention, the mixing speed is ≥1000 rpm and the mixing time is ≥5 minutes to ensure that the components are evenly dispersed to form a stable masterbatch.

[0051] Optionally, the rotation speed is ≥1200 rpm or 1000 rpm to 1200 rpm. The mixing time is ≥6 minutes or 5 minutes to 6 minutes.

[0052] In step 1) of the present invention, a twin-screw extruder with a length-to-diameter ratio of ≥40:1 is used to perform melt extrusion at a relatively low temperature (≤190° C.) to avoid material degradation and maintain the activity of the components.

[0053] Optionally, the aspect ratio is 40: 1 to 44: 1. The extrusion temperature is 150°C to 175°C, 175°C to 190°C.

[0054] In step 1) of the present invention, the weight percentages and specific selections of polypropylene, the first polyolefin elastomer, and erucamide are the same as those in the first aspect of the present invention and will not be described in detail herein.

[0055] In the preparation method of high-performance melt-blown elastic material without activation treatment provided by the present invention, step 2) is to mix the masterbatch with the second polyolefin elastomer, and melt them in an extruder at ≤250°C to form a uniform melt; after filtering and metering, the melt is extruded through a melt-blown die head with a pore size of 0.15 to 0.3 mm; after hot air flow drawing and side blowing cooling, the fiber diameter is controlled to be 2 to 20 μm to form a fiber web.

[0056] In step 2) of the present invention, the mass ratio and specific selection of the masterbatch and the second polyolefin elastomer are the same as those in the first aspect of the present invention, and will not be described in detail here.

[0057] In step 2) of the present invention, optionally, the melting is carried out in an extruder, and the melting temperature is 240-250°C, preferably 240°C.

[0058] In step 2) of the present invention, a melt-blowing die head with an aperture of 0.15 mm to 0.3 mm and a hole number of 1000 to 2000 holes / m is selected to accurately control the fiber diameter within the range of 2 to 20 μm to ensure the fineness and uniformity of the fiber.

[0059] Optionally, the fiber diameter is controlled to be 2-15.2 μm, 15.2-20 μm, 2-13 μm, 13-20 μm, etc. The number of pores can be selected to be 1000-1500 pores / m or 1500-2000 pores / m.

[0060] In step 2) of the present invention, the stretching and shaping of the fibers are controlled by hot air flow drawing and side-blowing cooling to achieve uniform shaping of the fiber web.

[0061] In step 2) of the present invention, the temperature of the hot air flow is 200-270° C., and the wind speed is 0.5-3 m / s. Optionally, the temperature of the hot air flow is 200-235° C. or 235-270° C., and the wind speed is 0.5-1.5 m / s or 1.5-3 m / s.

[0062] [High-performance melt-blown elastic material without radiative treatment]

[0063] The third aspect of the present invention provides a high-performance melt-blown elastic material that does not require an excitation treatment, which is prepared by the method provided by the second aspect of the present invention. The elastic difference between the MD and CD directions of the melt-blown elastic material is ≤10%, and the recovery rate is ≥85%.

[0064]

application

[0065] The fourth aspect of the present invention provides the application of the high-performance melt-blown elastic material that does not require activating treatment as described above in the fields of personal hygiene care and medical protection.

[0066] The beneficial effects of the present invention are further illustrated below in conjunction with embodiments.

[0067] In order to make the invention purpose, technical scheme and beneficial technical effect of the present invention clearer, the present invention is further described in detail below in conjunction with examples. However, it should be understood that the examples of the present invention are only for explaining the present invention, not for limiting the present invention, and the examples of the present invention are not limited to the examples given in the specification. The specific experimental conditions or operating conditions not specified in the examples are made under conventional conditions, or are made under the conditions recommended by the material supplier.

[0068] In addition, it should be understood that one or more method steps mentioned in the present invention do not exclude the existence of other method steps before or after the combination step or the insertion of other method steps between these explicitly mentioned steps, unless otherwise specified; it should also be understood that the combination connection relationship between one or more devices / apparatuses mentioned in the present invention does not exclude the existence of other devices / apparatuses before or after the combination device / apparatus or the insertion of other devices / apparatuses between these explicitly mentioned two devices / apparatuses, unless otherwise specified. Moreover, unless otherwise specified, the numbering of each method step is only a convenient tool for identifying each method step, and is not intended to limit the order of arrangement of each method step or the scope of the present invention. Changes or adjustments in their relative relationships should also be regarded as the scope of the present invention without substantially changing the technical content.

[0069] In the following examples, the reagents, materials and instruments used are all commercially available unless otherwise specified.

[0070] PP was purchased from Shandong Dawn New Materials Co., Ltd., model Z-1500;

[0071] The polyolefin elastomer was purchased from ExxonMobil Corporation Vistamaxx, brand 7050FL;

[0072] Erucic acid amide was purchased from Nantong Dongli New Materials, with a total amide content of ≥99.5%.

[0073] The elastic difference and recovery rate of the material in the MD and CD directions in the embodiments are determined according to GB_T24218.102-2022 Test methods for textile nonwovens Part 102: Determination of tensile elasticity.

[0074] Example 1

[0075] 1. Masterbatch preparation:

[0076] o Polypropylene (42%), polyolefin elastomer Vistamaxx 7050FL (42%) and erucamide (16%)

[0077] Mix by weight percentage.

[0078] o Mix in a high speed mixer at 1200 rpm for 6 minutes to ensure that the components are evenly dispersed.

[0079] o Through a twin-screw extruder with a length-to-diameter ratio of 44:1, it is melt-extruded at an extrusion temperature of 175°C, stretched, pelletized and dried to form a masterbatch.

[0080] 2. Web forming:

[0081] o The above masterbatch and polyolefin elastomer are mixed in proportion (masterbatch accounts for 12.5%, polyolefin elastomer accounts for 87.5%), and melted at 240° C. to form a uniform melt.

[0082] After being filtered and metered, the melt is extruded through a meltblown die with a pore size of 0.3 mm and a pore number of 1500 pores / m.

[0083] After hot air flow drawing (temperature 250℃) and side air cooling (temperature 20℃, wind speed 1.5m / s), the fiber diameter is controlled to be 15.2μm, and the fiber is formed into a web at a cooling height of 200mm.

[0084] 3. Finished product processing:

[0085] o Cut and roll the fiber web to produce a fiber web with a unit area mass of 100g / m 2 Finished elastic material.

[0086] o The test results show that the elastic difference between the material in the MD and CD directions is 8%, and the recovery rate is 88%.

[0087] Example 2

[0088] 1. Masterbatch preparation:

[0089] o Adjust the ratio to polypropylene (4.75%), polyolefin elastomer (82.75%) and erucamide (12.5%).

[0090] oOther preparation steps are the same as those in Example 1.

[0091] 2. Web forming:

[0092] o The fiber diameter is controlled at 13μm, which further improves the flexibility and elasticity of the material.

[0093] o The material has a 6% difference in elasticity between MD and CD directions and a recovery rate of 90%.

[0094] Compared with the traditional melt-blown elastic material that needs to be treated with activation, the material of the present invention can still obtain higher elastic performance and recovery rate without activation treatment. At the same time, the production process is simpler and the cost is lower, which has obvious advantages.

[0095] In summary, the present invention effectively overcomes various shortcomings of the prior art and has high industrial utilization value.

[0096] The above is only a preferred embodiment of the present invention, and is not any formal or substantial limitation of the present invention. It should be pointed out that ordinary technicians in this technical field can make several improvements and supplements without departing from the method of the present invention, and these improvements and supplements should also be regarded as the protection scope of the present invention. Any technician familiar with this profession, without departing from the spirit and scope of the present invention, can make some changes, modifications and evolutions of the technical content disclosed above, which are equivalent embodiments of the present invention; at the same time, any changes, modifications and evolutions of any equivalent changes made to the above embodiments based on the essential technology of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A high-performance melt-blown elastic material that does not require irradiation treatment, characterized in that: The raw materials of the melt-blown elastic material include a masterbatch and a second polyolefin elastomer; the mass ratio of the masterbatch to the second polyolefin elastomer is 1:(1-7); The raw materials of masterbatch include by weight percentage: Polypropylene 4% to 50%; 40% to 85% of the first polyolefin elastomer; Erucamide 5%~20%.

2. The high-performance melt-blown elastic material without the need for stimulating treatment according to claim 1, characterized in that: The melt flow index of the polypropylene is 100 to 1800 g / 10 min; and / or, the first polyolefin elastomer is Vistamaxx 7050FL; And / or, the second polyolefin elastomer is Vistamaxx 7050FL.

3. The high-performance melt-blown elastic material without the need for stimulating treatment according to claim 1, characterized in that: The raw material of the melt-blown elastic material also includes a functional additive, and the weight percentage of the functional additive in the masterbatch is 0.1% to 5%.

4. The high-performance melt-blown elastic material without the need for stimulating treatment according to claim 3, characterized in that: The functional auxiliary agent is selected from antioxidants or anti-ultraviolet auxiliary agents.

5. A method for preparing a high-performance melt-blown elastic material without the need for an energizing treatment, characterized in that: The preparation method comprises the following steps: 1) Preparation of masterbatch: polypropylene, the first polyolefin elastomer and erucic acid amide are mixed, and mixed in a high-speed mixer at a speed of ≥1000 rpm for ≥5 minutes to form a uniform mixture; melt extruded, stretched, pelletized and dried at a temperature of ≤190° C. by a twin-screw extruder with a length-to-diameter ratio of ≥40:1 to prepare a masterbatch; 2) Fiber web forming: the masterbatch is mixed with the second polyolefin elastomer, and melted in an extruder at ≤250°C to form a uniform melt; the melt is filtered and metered, and then extruded through a melt-blown die head with a pore size of 0.15 to 0.3 mm; the fiber is stretched by hot air flow and cooled by side blowing, and the fiber diameter is controlled to be 2 to 20 μm to form a fiber web; 3) Finished product processing: the fiber web is cut and rolled up to produce a meltblown elastic material.

6. The method for preparing a high-performance melt-blown elastic material without the need for an energizing treatment according to claim 5, characterized in that: In step 2), the material is melted in an extruder at a melting temperature of 240 to 250°C.

7. The method for preparing a high-performance melt-blown elastic material without the need for an energizing treatment according to claim 5, characterized in that: In step 2), the meltblowing die head has 1000 to 2000 holes / m.

8. The method for preparing a high-performance melt-blown elastic material without activating treatment according to claim 5, characterized in that: In step 2), the temperature of the hot air flow is 200-270° C., and the wind speed is 0.5-3 m / s.

9. A high-performance melt-blown elastic material that does not require energization treatment, prepared by the method according to any one of claims 5 to 8, characterized in that: The elastic difference of the melt-blown elastic material in the MD and CD directions is ≤10%, and the recovery rate is ≥85%.

10. Application of the high-performance melt-blown elastic material that does not require activating treatment as described in any one of items 1 to 4 and 9 of claim 1 in the field of personal hygiene care and medical protection.