Yellowing-resistant chest cotton as well as composite material and preparation method thereof

Abstract

The invention provides yellowing-resistant chest cotton as well as a combined material and a preparation method thereof. The yellowing-resistant chest cotton comprises 20-40% of bio-based polyether polyol, 15-55% of carbon dioxide-based polycarbonate polyether polyol, 5-10% of titanium dioxide, 1-5% of organic purple pigment, 1-5% of organic blue pigment and 2-30% of a bio-based dispersant. The preparation method comprises the following steps: adding the bio-based dispersing agent into the carbon dioxide-based polycarbonate polyether polyol and the bio-based soybean oil polyol, uniformly stirring, adding the titanium dioxide, the organic purple pigment and the organic blue pigment, dispersing for 15-25 minutes at the speed of 1000-2000 rpm, adding the grinding medium, grinding for 1.5-2.5 hours by using an oscillator, and discharging when the fineness is lower than 20 microns. The heat storage stability of the product can be improved, VOC and odor are reduced, the porosity, the air permeability and the tensile strength are enhanced, the anti-yellowing performance is achieved, and the environmental protection property and comfort are improved.

Description

Technical Field

[0001] The invention relates to the technical field of polyurethane soft foam materials, and more specifically to yellowing-resistant bra cotton and a composite material thereof and a preparation method thereof. Background Art

[0002] The existing bra sponge is mainly made of polyurethane soft foam, and the commonly used raw materials include aromatic diisocyanates. These materials are easy to form chromophores such as quinone structures under the action of light, which leads to the problem of yellowing of sponges. In the molding process of bra sponges, the yellowing problem is more serious because it needs to be hot-pressed at 180 degrees. At present, the technology and principle of whitening and anti-yellowing mainly rely on anti-yellowing additives and fluorescent brighteners, which are mainly aimed at the influence of heat, oxygen and light. Anti-yellowing additives mainly include antioxidants and light stabilizers. Antioxidants prevent polymer self-oxidation by capturing free radicals, while light stabilizers are mainly ultraviolet absorbers. Fluorescent brighteners compensate for the yellowish color in the matrix by absorbing invisible ultraviolet light and converting it into visible light, making the product appear whiter and brighter. However, there are problems with the use of these two types of additives in bra sponges to resist yellowing: on the one hand, they are not environmentally friendly, and long-term direct contact with the human body may be harmful to health; on the other hand, fluorescent brighteners need visible light excitation to work, and there is no condition for long-term exposure to visible light when the bra sponge is worn close to the body.

[0003] In the process of implementing the embodiments of the present invention, the inventors found that there are at least the following problems or defects in the prior art: the existing bra cotton materials are insufficient in terms of environmental protection, human health safety and yellowing resistance, especially when used close to the body, the traditional anti-yellowing additives and fluorescent brighteners cannot meet the market's demand for environmental protection and health due to their potential health risks and usage limitations. In addition, the prior art also has limitations in improving the open porosity, air permeability, tensile strength and other aspects of polyurethane soft foam, and these performance deficiencies affect the wearing comfort of the bra cotton. Summary of the invention

[0004] The invention provides a yellowing-resistant bra cotton and a composite material thereof and a preparation method thereof.

[0005] In the first aspect of the present invention, a bio-based functional composite material for yellowing-resistant bra cotton is provided, comprising the following raw materials in percentage by mass:

[0006] Bio-based polyether polyol 20-40%; CO2-based polycarbonate polyether polyol 15-55%; titanium dioxide 5-10%; organic purple pigment 1-5%; organic blue pigment 1-5%; bio-based dispersant 2-30%.

[0007] Furthermore, the bio-based polyether polyol is one or more of soybean oil polyether polyol, palm oil polyether polyol or coconut oil polyether polyol.

[0008] Furthermore, the bio-based dispersant is one or more of alkyl glycoside, fatty acid phosphate, rhamnolipid, trehalolipid or sophorolipid.

[0009] In a second aspect of the present invention, a method for preparing a bio-based functional composite material for yellowing-resistant bra cotton is provided, comprising the following steps:

[0010] Adding a bio-based dispersant to the carbon dioxide-based polycarbonate polyether polyol and the bio-based soybean oil polyol, and stirring them evenly;

[0011] Add titanium dioxide, organic purple pigment, and organic blue pigment, and disperse at a speed of 1000-2000rpm for 15-25min;

[0012] After adding the grinding media, grind with an oscillator for 1.5-2.5 hours until the material has a fineness of less than 20 μm.

[0013] Furthermore, the grinding media are glass beads or zirconia beads.

[0014] In the third aspect of the present invention, a yellowing-resistant bra sponge is provided, comprising the bio-based functional combination material.

[0015] In a fourth aspect of the present invention, a method for preparing yellowing-resistant bra cotton is provided, characterized in that it comprises the following steps:

[0016] Mixing polyether polyol, water, silicone oil, amine catalyst, tin catalyst, foaming agent, toluene diisocyanate and bio-based functional composite material for foaming;

[0017] The foamed mixture is hot-pressed into a mold at a temperature of 180° C. for 3 minutes.

[0018] Furthermore, the molecular weight of the polyether polyol is 2000-8000. Calculated by mass percentage, the raw materials of the bra cotton include: 60-70% of the polyether polyol, 1.5-4% of water, 0.5-2% of silicone oil, 0.1-0.3% of amine catalyst, 0.1-0.3% of tin catalyst, 8-15% of foaming agent, 20-30% of toluene diisocyanate, and 0.5-1% of bio-based functional composite material.

[0019] Furthermore, the method further comprises the following steps:

[0020] The mixing and foaming process of each raw material is stirred at a speed of 500-1000 rpm for 3-5 minutes;

[0021] After hot pressing and molding in the mold, the yellowing-resistant bra cotton is post-treated, and the post-treatment includes heat treatment at 40-60° C. for 2-4 hours and placing in a ventilated environment for 12-24 hours.

[0022] According to the above-mentioned embodiments of the present invention, at least the following beneficial effects are achieved: the bio-based functional composite material for yellowing-resistant bra sponge of the present invention and the preparation method thereof can improve the environmental performance and human health safety of the bra sponge. By adopting bio-based raw materials and a formula without fluorescent whitening agents, the possible harm to the environment and human body is reduced, while VOC and odor are reduced, making the bra sponge more suitable for close-fitting use. In addition, the technical solution of the present invention improves the anti-yellowing performance of the sponge through the use of a special pigment combination and bio-based color paste, and can maintain the original color even under long-term light and high temperature conditions, thereby extending the service life of the product.

[0023] In addition, the present invention can also improve the porosity, air permeability and tensile strength of polyurethane soft foam, thereby improving the wearing comfort of bra cotton. This improvement not only enhances the practicality of bra cotton, but also provides users with a healthier and more comfortable wearing experience. Through the optimized preparation method, the bra cotton of the present invention exhibits superior performance in terms of thermal storage stability, anti-yellowing performance, VOC, odor, porosity, air permeability and tensile strength. Compared with the prior art, the present invention provides a more environmentally friendly, durable and comfortable bra cotton solution. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and other objects, features and advantages of the exemplary embodiments of the present invention will become readily understood by reading the detailed description below with reference to the accompanying drawings. In the accompanying drawings, several embodiments of the present invention are shown in an exemplary and non-limiting manner, in which:

[0025] Figure 1 A schematic flow chart of a method for preparing a bio-based functional composite material for yellowing-resistant bra cotton provided in one embodiment of the present invention. DETAILED DESCRIPTION

[0026] The principles and spirit of the present invention will be described below with reference to several exemplary embodiments. It should be understood that these embodiments are provided only to enable those skilled in the art to better understand and implement the present invention, and are not intended to limit the scope of the present invention in any way. On the contrary, these embodiments are provided to make the present invention more thorough and complete, and to fully convey the scope of the present invention to those skilled in the art.

[0027] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. All features disclosed in this specification, or steps in all methods or processes disclosed, except for mutually exclusive characteristics and / or steps, can be combined in any way, unless otherwise described, and can be replaced by other equivalent or alternative features with similar purposes, that is, unless otherwise described, each feature is only one embodiment in a series of equivalent or similar features.

[0028] In some embodiments, a bio-based functional composite material for yellowing-resistant bra cotton includes the following raw materials in percentage by weight:

[0029] Bio-based polyether polyol 20-40%; CO2-based polycarbonate polyether polyol 15-55%; titanium dioxide 5-10%; organic purple pigment 1-5%; organic blue pigment 1-5%; bio-based dispersant 2-30%.

[0030] It should be noted that this embodiment describes a method for preparing a bio-based functional composite material for yellowing-resistant bra cotton, which involves the mixing and processing of multiple raw materials to ensure that the final product has good yellowing resistance and bio-based characteristics. In this process, bio-based polyether polyol refers to polyether polyol made from biomass raw materials, which can be derived from plants or animals and are renewable and environmentally friendly.

[0031] Specifically, the bio-based functional composite material includes 20-40% bio-based polyether polyol, 15-55% carbon dioxide-based polycarbonate polyether polyol, 5-10% titanium dioxide, 1-5% organic purple pigment, 1-5% organic blue pigment, and 2-30% bio-based dispersant. The specific parameters of these raw materials are set as follows: the bio-based polyether polyol can be one or more of soybean oil polyether polyol, palm oil polyether polyol or coconut oil polyether polyol; the bio-based dispersant can be one or more of alkyl glycoside, fatty acid phosphate, rhamnolipid, trehalose lipid or sophorolipid. The proportions of these raw materials can be adjusted according to actual needs to meet different performance requirements.

[0032] Preferably, the preparation method of the bio-based functional composite material comprises the following steps: first, adding a bio-based dispersant to a carbon dioxide-based polycarbonate polyether polyol and a bio-based soybean oil polyol, and stirring them evenly; then, adding titanium dioxide, an organic purple pigment, and an organic blue pigment, and dispersing them at a speed of 1000-2000 rpm for 15-25 minutes; finally, adding a grinding medium, and grinding with an oscillator for 1.5-2.5 hours until the fineness is less than 20 μm.

[0033] Furthermore, in actual operation, the grinding media can be glass beads or zirconium oxide beads, and the selection of these grinding media can be determined according to the hardness of the material and the required fineness requirements. In addition, the specific speed and time of dispersion and grinding can also be appropriately adjusted according to experimental conditions and equipment performance to achieve the best preparation effect.

[0034] In some embodiments, the bio-based polyether polyol is one or more of soybean oil polyether polyol, palm oil polyether polyol, or coconut oil polyether polyol.

[0035] It should be noted that this embodiment describes in detail the specific composition of a bio-based functional composite material for yellowing-resistant bra cotton, and particularly points out that the type of bio-based polyether polyol can be one or more of soybean oil polyether polyol, palm oil polyether polyol or coconut oil polyether polyol. The bio-based polyether polyol mentioned here refers to those polyether polyols obtained by chemical synthesis based on biomass resources, such as vegetable oil or animal fat, which are regarded as environmentally friendly raw materials due to their renewable and biodegradable properties.

[0036] Specifically, the selection of bio-based polyether polyols varies according to their hydroxyl value and molecular weight. For example, soybean oil polyether polyols may have higher molecular weight and hydroxyl value, which will affect their performance in the final product, such as flexibility and strength. Palm oil polyether polyols and coconut oil polyether polyols may have different physical and chemical properties due to the different fatty acid chain lengths from which they are derived. In practical applications, suitable bio-based polyether polyols can be selected according to the required foam properties and environmental adaptability, and multiple bio-based polyether polyols can be mixed to optimize product performance.

[0037] Preferably, the specific parameters of the bio-based polyether polyol in this embodiment are set as follows: the hydroxyl value of soybean oil polyether polyol is 56 and the molecular weight is 3000; the hydroxyl value of palm oil polyether polyol is 20 and the molecular weight is 6000; the hydroxyl value of coconut oil polyether polyol is 70 and the molecular weight is 1500. These parameters are determined according to the chemical structure of the raw materials and the expected physical properties.

[0038] Furthermore, as an alternative, other types of polyether polyols derived from vegetable oils or animal fats can also be selected, as long as they can meet the required hydroxyl value and molecular weight range and have similar environmental protection characteristics and bio-based content. In addition, according to specific application requirements, the proportion of these bio-based polyether polyols can also be adjusted to obtain the best foam structure and performance.

[0039] In some embodiments, the bio-based dispersant is one or more of an alkyl glycoside, a fatty acid phosphate, a rhamnolipid, a trehalolipid, or a sophorolipid.

[0040] It should be noted that this embodiment describes in detail a method for preparing a bio-based functional composite material for yellowing-resistant bra cotton, and particularly points out that the bio-based dispersant can be one or more of alkyl glycosides, fatty acid phosphates, rhamnolipids, trehalose lipids or sophorolipids. Here, bio-based dispersants refer to those derived from biomass, which are used in industrial production to improve the dispersibility of pigments and other insoluble substances in liquid media and enhance the uniformity and stability of materials.

[0041] Specifically, the selection of bio-based dispersants is based on their chemical structure and application characteristics. For example, alkyl glycosides are non-ionic surfactants synthesized from sugars and fatty alcohols, which have good biodegradability and low toxicity; fatty acid phosphates are compounds obtained by the reaction of fatty acids and phosphoric acid, which have excellent wetting and dispersing abilities. Rhamnolipids, trehalose lipids and sophorolipids are natural glycolipids extracted from plants. They not only have bio-based properties, but also provide additional functionality, such as antibacterial and antioxidant properties. In practical applications, suitable bio-based dispersants can be selected according to the required dispersion effect and environmental adaptability, and multiple bio-based dispersants can be mixed and used to optimize product performance.

[0042] Preferably, the specific parameters of the bio-based dispersant in this embodiment are set as follows: the addition amount of alkyl polyglycoside 0810 is 5%, and the addition amount of fatty acid phosphate C10-12 is also 5%. These parameters are obtained based on experimental data and material performance tests to ensure the best dispersion effect of the pigment in the polyurethane soft foam substrate.

[0043] Furthermore, as an alternative, other types of bio-based dispersants, such as glucose or starch-based derivatives, can also be selected as long as they can meet the required dispersing effect and bio-based content. In addition, according to specific application requirements, the proportion and addition order of these bio-based dispersants can also be adjusted to obtain the best foam structure and performance.

[0044] In some embodiments, the method for preparing the yellowing-resistant bra cotton bio-based functional combination material is as follows: Figure 1 As shown, the following steps are included:

[0045] Step 101, adding a bio-based dispersant to the carbon dioxide-based polycarbonate polyether polyol and the bio-based soybean oil polyol, and stirring them evenly;

[0046] Step 102, adding titanium dioxide, organic purple pigment, and organic blue pigment, and dispersing at a speed of 1000-2000 rpm for 15-25 minutes;

[0047] Step 103, after adding the grinding medium, grind with an oscillator for 1.5-2.5 hours, and discharge the material with a fineness less than 20 μm.

[0048] It should be noted that this embodiment describes in detail the preparation method of the bio-based functional composite material for yellowing-resistant bra cotton, which includes key steps such as mixing, dispersing and grinding. Here, the bio-based functional composite material refers to a mixture composed of a series of bio-based raw materials, which work together to improve the performance of the bra cotton, especially in terms of yellowing resistance.

[0049] Specifically, the preparation method first involves mixing CO2-based polycarbonate polyether polyol and bio-based soybean oil polyol, and adding a bio-based dispersant for stirring. In this step, CO2-based polycarbonate polyether polyol is a polyether polyol derived from carbon dioxide, which is synthesized through a chemical process and has a low carbon footprint; bio-based soybean oil polyol is a polyol extracted from soybean oil, which has renewable and biodegradable properties. During the stirring process, it is necessary to ensure that the two polyols and dispersants are fully mixed to facilitate the subsequent uniform dispersion of the pigment. The specific stirring speed and time can be adjusted according to laboratory conditions and industrial production equipment to achieve the best mixing effect.

[0050] Preferably, the dispersing step in the preparation method involves adding titanium dioxide, organic violet pigment and organic blue pigment to the above mixture and dispersing at a speed of 1000-2000rpm for 15-25 minutes. In this step, titanium dioxide is a commonly used white pigment used to improve the whiteness and hiding power of the product; organic violet pigment and organic blue pigment are used to absorb ultraviolet light and reflect visible light, thereby enhancing the yellowing resistance of the product. The selection of dispersion speed and time is crucial for the uniform distribution of pigments and directly affects the color and performance of the final product. The preferred dispersion speed and time can be fine-tuned according to the characteristics of the pigment and the desired dispersion effect. In the grinding step, after adding the grinding media, use an oscillator to grind for 1.5-2.5 hours until the fineness is less than 20μm. The choice of grinding media, such as glass beads or zirconia beads, will affect the fineness and uniformity of the final product.

[0051] More specifically, the particle size, hardness and addition amount of the grinding media are all parameters that can be adjusted to suit different production needs and product specifications. In addition, the grinding time and speed can also be optimized according to actual production conditions to ensure sufficient refinement and uniform distribution of the pigment.

[0052] In some embodiments, the grinding media are glass beads or zirconia beads.

[0053] It should be noted that this embodiment further describes the specific selection of grinding media in the preparation method of the bio-based functional composite material for yellowing-resistant bra cotton. Here, grinding media refers to a substance used to help disperse and refine pigment particles during the grinding process, and its selection has an important impact on the performance of the final product.

[0054] Specifically, the grinding media can be glass beads or zirconia beads. Glass beads are spherical particles made of glass material, which have good wear resistance and chemical stability and are often used in industrial grinding processes; zirconia beads are spherical particles made of zirconium oxide, which are known for their high hardness and wear resistance and are suitable for occasions that require finer grinding. When selecting grinding media, its hardness, particle size distribution, chemical stability and degree of wear on pigment particles need to be considered.

[0055] More specifically, the settings of these parameters will directly affect the grinding efficiency and the fineness of the final product. For example, zirconium oxide beads may be more suitable for applications that require finer grinding due to their high hardness, while glass beads may be more popular due to their cost-effectiveness.

[0056] Preferably, the selection and use of grinding media can be adjusted according to specific production conditions and product requirements. For example, if a finer final product is required, smaller zirconia beads can be selected; if cost factors are considered, larger glass beads can be selected.

[0057] Furthermore, the amount of grinding media added is also a parameter that can be optimized. Too much grinding media may cause excessive wear, while too little may affect the grinding effect. In actual operation, the best grinding media type, particle size, hardness and addition amount can be determined through experiments to achieve the best grinding effect and product performance.

[0058] Furthermore, as an alternative, other types of grinding media, such as ceramic beads or stainless steel beads, may also be considered as long as they can meet the desired grinding effect and product performance requirements.

[0059] In some embodiments, a yellowing-resistant bra sponge is provided, comprising the bio-based functional combination material.

[0060] It should be noted that this embodiment describes the specific composition of a yellowing-resistant bra sponge, which includes the aforementioned bio-based functional composite material. Here, the yellowing-resistant bra sponge refers to a special polyurethane soft foam material, which improves its yellowing resistance by adding a specific bio-based functional composite material, and can maintain its original color even under long-term light or high temperature conditions.

[0061] Specifically, the mass percentage of the bio-based functional combination material in the anti-yellowing bra sponge is 1-5%. This means that the proportion of the bio-based functional combination material in the total mass of the bra sponge will not exceed 5%. Such a proportion can ensure the material's anti-yellowing performance without affecting other physical properties of the bra sponge too much. In actual production, the amount of bio-based functional combination material added can be adjusted according to the specific application and performance requirements of the bra sponge to achieve the best performance balance.

[0062] Preferably, the method for preparing the yellowing-resistant bra sponge further includes specific steps, such as mixing and foaming polyether polyol, water, silicone oil, A33, T-9, MC, TDI and bio-based functional combination materials, and then hot-pressing through a mold at a temperature of 180° C. for 3 minutes. These steps ensure that the bio-based functional combination materials are evenly distributed in the bra sponge and form a uniform foam structure.

[0063] Furthermore, as an alternative, the temperature and time of hot pressing can be adjusted, or different mold designs can be used to adapt to different production conditions and product specifications. In addition, different catalysts or foam stabilizers can be considered during the foaming process to optimize the formation and stability of the foam. These adjustments are all aimed at improving the yellowing resistance of the bra sponge while maintaining its comfort and durability.

[0064] It should be noted that this embodiment describes in detail the preparation method of the yellowing-resistant bra cotton, and particularly points out the mass percentage of each raw material in the preparation process. Here, the mass percentage refers to the proportion of each raw material in the total mass of the mixture, which is a key parameter to ensure that the bra cotton has specific properties.

[0065] Specifically, the molecular weight of the polyether polyol is 2000-8000. According to the mass percentage, the raw materials of the bra cotton include: 60-70% of the polyether polyol, 1.5-4% of water, 0.5-2% of silicone oil, 0.1-0.3% of amine catalyst, 0.1-0.3% of tin catalyst, 8-15% of foaming agent, 20-30% of toluene diisocyanate, and 0.5-1% of bio-based functional combination material. These parameters are carefully adjusted according to the physical properties and chemical stability requirements of the bra cotton. For example, water is used as part of the foaming agent here to help control the density and open porosity of the foam; silicone oil is used as a softener for soft foam to improve the feel and elasticity. A33, T-9, MC and TDI are commonly used chemical raw materials in the production of polyurethane foam, and their proportions directly affect the hardness, strength and yellowing resistance of the foam.

[0066] Preferably, the mixing and foaming process of these raw materials also includes a specific stirring speed and time. The stirring speed is 500-1000 rpm and the stirring time is 3-5 minutes. These conditions help to ensure that the raw materials are mixed evenly and form a stable foam structure. As an alternative, the stirring speed and time can be adjusted according to the specific production equipment and raw material characteristics to obtain the best mixing effect.

[0067] Furthermore, after hot pressing in the mold, the anti-yellowing bra foam can be post-processed, such as heat treatment at 40-60°C for 2-4 hours and placed in a ventilated environment for 12-24 hours. These steps help stabilize the foam structure and improve the durability and anti-yellowing performance of the product. These post-processing steps can be adjusted according to environmental conditions and product requirements to achieve the best product quality.

[0068] In some embodiments, a method for preparing yellowing-resistant bra cotton is provided, comprising the following steps:

[0069] Mixing water polyether polyol, water, silicone oil, A33, T-9, MC, TDI and bio-based functional composite materials for foaming;

[0070] The foamed mixture is hot-pressed into a mold at a temperature of 180° C. for 3 minutes.

[0071] It should be noted that the present embodiment relates to a method for preparing yellowing-resistant bra sponge, which includes the key steps of mixed foaming and hot pressing. Here, the yellowing-resistant bra sponge refers to a special polyurethane soft foam material, which improves its yellowing resistance through a specific preparation method and can maintain its original color even under long-term light or high temperature conditions.

[0072] Specifically, the preparation method of the yellowing-resistant bra cotton includes mixing and foaming polyether polyols, water, silicone oil, A33, T-9, MC, TDI and bio-based functional composite materials, and then hot-pressing the foamed mixture into a mold. In this process, mixed foaming refers to the process of mixing various raw materials in a certain proportion to produce foam through chemical reactions; hot pressing molding refers to molding the foamed foam material under a certain temperature and pressure to produce the desired product shape. The hot pressing temperature is 180°C and the hot pressing time is 3 minutes. These parameters are the key conditions for preparing yellowing-resistant bra cotton, which can ensure the physical properties and yellowing resistance of the material.

[0073] Preferably, in addition to the above steps, the preparation method may further include stirring the raw material mixing and foaming process at a stirring speed of 500-1000rpm for 3-5 minutes. This step helps to ensure that the raw materials are mixed evenly, thereby affecting the uniformity of the foam and the quality of the product. After hot pressing and molding in the mold, the yellowing-resistant bra sponge may also be post-treated, including heat treatment at 40-60°C for 2-4 hours and placement in a ventilated environment for 12-24 hours. These post-processing steps help stabilize the foam structure and improve the durability and yellowing resistance of the product.

[0074] Furthermore, as an alternative, the stirring speed, time, and temperature and time of heat treatment can be adjusted according to specific production conditions and product requirements, or different mold designs and hot pressing processes can be used to adapt to different production scales and product specifications.

[0075] It should be noted that this embodiment describes in detail the specific requirements for the stirring conditions and post-processing steps in the process of mixing and foaming each raw material in the preparation method of the yellowing-resistant bra sponge. Here, the stirring conditions refer to the speed and time parameters set in the raw material mixing stage to ensure uniform mixing; the post-processing step refers to the additional treatment performed after hot pressing to further improve product performance.

[0076] Specifically, in the preparation method of the yellowing-resistant bra sponge, the raw material mixing and foaming process is stirred at a stirring speed of 500-1000rpm and a stirring time of 3-5 minutes. The stirring speed refers to the number of rotations of the stirrer per unit time, which is an important factor affecting the uniformity of the raw material mixing; the stirring time refers to the length of time the stirrer continuously stirs the raw materials, which also affects the mixing effect of the raw materials. After hot pressing and molding in the mold, the yellowing-resistant bra sponge is post-treated, including heat treatment at 40-60°C for 2-4 hours, and placing it in a ventilated environment for 12-24 hours. Heat treatment refers to heating the molded bra sponge at a controlled temperature to promote the stability of the internal structure of the material; placing it in a ventilated environment refers to allowing the bra sponge to cool and dry naturally under natural ventilation or forced ventilation to reduce residual volatile organic compounds.

[0077] Preferably, these operation steps can be adjusted according to specific production conditions and product requirements. For example, the stirring speed and time can be optimized according to the viscosity of the raw materials and the size of the mixing container to achieve the best mixing effect. The temperature and time of the heat treatment can also be adjusted according to the specific material properties and required performance requirements of the bra cotton to ensure the stability and durability of the material. The time of placement in a ventilated environment can be adjusted according to the humidity and temperature conditions of the environment to ensure that the bra cotton has good performance in subsequent use.

[0078] Further, as an alternative, other types of post-treatment methods, such as vacuum drying or microwave treatment, can also be explored to shorten the processing time or improve the processing efficiency. These adjustments are all aimed at improving the yellowing resistance of the bra cotton while maintaining its comfort and durability.

[0079] In some embodiments, the following steps are also included:

[0080] The mixing and foaming process of each raw material is stirred at a speed of 500-1000 rpm for 3-5 minutes;

[0081] After hot pressing and molding in the mold, the yellowing-resistant bra cotton is post-treated, and the post-treatment includes heat treatment at 40-60° C. for 2-4 hours and placing in a ventilated environment for 12-24 hours.

[0082] It should be noted that this embodiment further describes the additional steps in the preparation method of the yellowing-resistant bra cotton, in addition to stirring and hot pressing. Here, the additional steps refer to the operations added outside the basic preparation process to improve product performance or meet specific requirements.

[0083] Specifically, in the preparation method of the yellowing-resistant bra cotton, in addition to stirring and hot pressing, the mixed foaming process of each raw material is also stirred, the stirring speed is 500-1000rpm, and the stirring time is 3-5 minutes. The mixed foaming process refers to the process of generating foam through chemical reaction during the raw material mixing stage, which is crucial to the density and structure of the final product. The specific setting of the stirring speed and time depends on the characteristics of the raw materials and the required foam characteristics, such as the fineness and uniformity of the foam.

[0084] Preferably, in addition to stirring and hot pressing, the preparation method may further include the step of post-treating the yellowing-resistant bra cotton after hot pressing the mold. The post-treatment includes heat treatment at 40-60°C for 2-4 hours, and placing in a ventilated environment for 12-24 hours. Heat treatment refers to heating the molded bra cotton at a controlled temperature to promote the stability of the internal structure of the material and the completion of the cross-linking reaction; placing in a ventilated environment refers to allowing the bra cotton to cool and dry naturally under natural ventilation or forced ventilation to reduce residual volatile organic compounds. These post-processing steps help to improve the durability and yellowing resistance of the product, ensuring that the product maintains stable performance during long-term use.

[0085] More specifically, the conditions of these post-treatment steps can be adjusted according to specific product requirements and environmental conditions. For example, the temperature and time of the heat treatment can be adjusted according to the specific material characteristics and required performance requirements of the bra sponge to ensure the stability and durability of the material. The time of placement in a ventilated environment can also be adjusted according to the humidity and temperature conditions of the environment to ensure that the bra sponge has good performance in subsequent use.

[0086] Further, as an alternative, other types of post-treatment methods, such as vacuum drying or microwave treatment, can also be considered to shorten the processing time or improve the processing efficiency. These adjustments are all aimed at improving the yellowing resistance of the bra cotton while maintaining its comfort and durability.

[0087] Example 1

[0088] 1. Preparation of bio-based functional composite materials: weigh the following raw materials by mass percentage:

[0089] Soybean oil polyether polyol (hydroxy ester 56, molecular weight 3000) 40%, carbon dioxide based polycarbonate polyether polyol (hydroxy ester 65, molecular weight 2000, cyclocarbonate content 40%, ethylene oxide EO30%, propylene oxide EO30%) 30%, titanium dioxide 5%, organic purple pigment 1%, organic blue pigment 1%, alkyl glucoside 0810 5%, fatty acid phosphate C10-12 5%.

[0090] Add alkyl polyglycoside 0810 and fatty acid phosphate C10-12 to carbon dioxide-based polycarbonate polyether polyol and soybean oil polyether polyol, and stir well.

[0091] Add titanium dioxide, organic violet pigment and organic blue pigment and disperse at a speed of 1500 rpm for 20 minutes.

[0092] After adding glass beads as grinding media, the mixture was ground with an oscillator for 2 hours until the fineness reached 15 μm, thereby obtaining a bio-based functional composite material A.

[0093] 2. Preparation of yellowing-resistant bra cotton: weigh the following raw materials:

[0094] Polyether polyol 3010 (Dow) 300g, water 8g, silicone oil (Evonik 846) 4g, A33 (triethylenediamine) 0.8g, T-9 (stannous octoate) 1.0g, MC (blowing agent dichloromethane) 40.5g, TDI (toluene diisocyanate) 115g, bio-based functional component A 3g.

[0095] Polyether polyol 3010, water, silicone oil, A33, T-9, MC, TDI and bio-based functional combination material A are mixed and foamed.

[0096] The foamed mixture was hot-pressed into a mold at a temperature of 180° C. for 3 minutes to obtain a yellowing-resistant bra cotton sample 1.

[0097] Example 2

[0098] 1. Preparation of bio-based functional composite materials: weigh the following raw materials by mass percentage:

[0099] Palm oil polyether polyol (hydroxy ester 20, molecular weight 6000) 35%, carbon dioxide based polycarbonate polyether polyol (hydroxy ester 100, molecular weight 1000, cyclocarbonate content 30%, ethylene oxide EO 20%, propylene oxide EO 50%) 20%, titanium dioxide 5%, organic purple pigment 3%, organic blue pigment 3%, rhamnolipid 10%, trehalose lipid 10%.

[0100] Rhamnolipid and trehalose lipid are added to carbon dioxide-based polycarbonate polyether polyol and palm oil polyether polyol, and the mixture is stirred evenly.

[0101] Add titanium dioxide, organic violet pigment and organic blue pigment, and disperse at a speed of 1800 rpm for 18 minutes.

[0102] After adding zirconium oxide beads as grinding media, the material was ground with an oscillator for 1.8 hours until the fineness reached 18 μm, thereby obtaining a bio-based functional composite material B.

[0103] 2. Preparation of yellowing-resistant bra cotton: weigh the following raw materials by mass percentage:

[0104] Polyether polyol 3010 (Dow) 300g, water 12g, silicone oil (Evonik 846) 6g, A33 (triethylenediamine) 1g, T-9 (stannous octoate) 1.2g, MC (blowing agent dichloromethane) 41g, TDI (toluene diisocyanate) 110g, bio-based functional component B 4g.

[0105] The polyether polyol 3010, water, silicone oil, A33, T-9, MC, TDI and bio-based functional combination material B are mixed and foamed.

[0106] The foamed mixture was hot-pressed into a mold at a temperature of 180° C. for 3 minutes to obtain a yellowing-resistant bra cotton sample 2.

[0107] Example 3

[0108] 1. Preparation of bio-based functional composite materials: weigh the following raw materials by mass percentage:

[0109] Coconut oil polyether polyol (hydroxy ester 70 molecular weight 1500) 25%, carbon dioxide based polycarbonate polyether polyol (hydroxy ester 200, molecular weight 500, cyclocarbonate content 50%, ethylene oxide EO25%, propylene oxide EO25%) 30%, titanium dioxide 5%, organic purple pigment 2%, organic blue pigment 2%, alkyl glycoside 1214 15%, sophorolipid 5%.

[0110] Add alkyl glucoside 1214 and sophorolipids to carbon dioxide-based polycarbonate polyether polyol and coconut oil polyether polyol, and stir well.

[0111] Add titanium dioxide, organic violet pigment and organic blue pigment and disperse at a speed of 1200 rpm for 22 minutes.

[0112] After adding glass beads as grinding media, the mixture was ground with an oscillator for 2.2 hours until the fineness reached 16 μm, thereby obtaining a bio-based functional composite material C.

[0113] 2. Preparation of yellowing-resistant bra cotton: weigh the following raw materials by weight percentage:

[0114] Polyether polyol 3010 (Dow) 300g, water 10g, silicone oil (Evonik 846) 5g, A33 (triethylenediamine) 0.8g, T-9 (stannous octoate) 1.2g, MC (blowing agent dichloromethane) 40g, TDI (toluene diisocyanate) 105g, bio-based functional component C 3g.

[0115] Polyether polyol 3010, water, silicone oil, A33, T-9, MC, TDI and bio-based functional combination material C are mixed and foamed.

[0116] The foamed mixture was hot-pressed into a mold at a temperature of 180° C. for 3 minutes to obtain yellowing-resistant bra cotton sample 3.

[0117] Comparative Example 1

[0118] 1. Preparation of traditional bra cotton (without adding bio-based functional combination materials), weigh the following raw materials: polyether polyol 3010 (Dow) 300g, water 8g, fluorescent brightener KSN 3g, silicone oil (Evonik 846) 3.6g, A33 0.6g, T-9 0.9g, MC40.5g, TDI 111.5g.

[0119] Mix the above raw materials and foam them.

[0120] The foamed mixture was hot-pressed into a mold at a temperature of 180° C. for 3 minutes to obtain a traditional bra cotton sample.

[0121] Performance Testing

[0122] The yellowing-resistant bra cotton samples 1-3 prepared in the above examples 1-3 and the traditional bra cotton sample prepared in comparative example 1 were subjected to performance tests, and the test items included heat storage stability, one-month anti-yellowing performance, VOC, odor, openness, air permeability, and tensile strength. The test results are shown in the following table:

[0123]

[0124]

[0125] The tensile strength is tested according to ISO1798 standard, and the air permeability is tested according to ASTM D3574-2017 (G). From the above test results, it can be seen that the yellowing-resistant bra cotton prepared by the present invention is superior to traditional bra cotton in terms of thermal storage stability, odor, openness, air permeability, tensile strength and anti-yellowing performance, and has good performance.

[0126] The above embodiments are only some implementation methods of the present invention, and they can be adjusted and improved as needed in practical applications, which should all be included in the protection scope of the present invention.

Claims

1. A bio-based functional composite material for yellowing-resistant bra cotton, characterized in that: The following raw materials are included in mass percentage: Bio-based polyether polyol 20-40%; CO2-based polycarbonate polyether polyol 15-55%; titanium dioxide 5-10%; organic purple pigment 1-5%; organic blue pigment 1-5%; bio-based dispersant 2-30%.

2. The bio-based functional composite material for yellowing-resistant bra cotton according to claim 1, characterized in that: The bio-based polyether polyol is one or more of soybean oil polyether polyol, palm oil polyether polyol or coconut oil polyether polyol.

3. The bio-based functional composite material for yellowing-resistant bra cotton according to claim 1, characterized in that: The bio-based dispersant is one or more of alkyl glycoside, fatty acid phosphate, rhamnolipid, trehalolipid or sophorolipid.

4. A method for preparing a bio-based functional composite material for yellowing-resistant bra cotton according to any one of claims 1 to 3, characterized in that: The following steps are involved: Adding a bio-based dispersant to the carbon dioxide-based polycarbonate polyether polyol and the bio-based soybean oil polyol, and stirring them evenly; Add titanium dioxide, organic purple pigment, and organic blue pigment, and disperse at a speed of 1000-2000rpm for 15-25min; After adding the grinding media, grind with an oscillator for 1.5-2.5 hours until the material has a fineness of less than 20 μm.

5. The preparation method according to claim 4, characterized in that: The grinding media are glass beads or zirconium oxide beads.

6. A yellowing-resistant bra cotton, characterized in that: The bio-based functional composite material comprises any one of claims 1 to 3.

7. A method for preparing the yellowing-resistant bra cotton according to claim 6, characterized in that: The following steps are involved: Mixing polyether polyol, water, silicone oil, amine catalyst, tin catalyst, foaming agent, toluene diisocyanate and bio-based functional composite material for foaming; The foamed mixture is hot-pressed into a mold at a temperature of 180° C. for 3 minutes.

8. The preparation method according to claim 7, characterized in that: The molecular weight of the polyether polyol is 2000-8000. Calculated by mass percentage, the raw materials of the bra cotton include: 60-70% of the polyether polyol, 1.5-4% of water, 0.5-2% of silicone oil, 0.1-0.3% of amine catalyst, 0.1-0.3% of tin catalyst, 8-15% of foaming agent, 20-30% of toluene diisocyanate, and 0.5-1% of bio-based functional composite material.

9. The preparation method according to claim 8, characterized in that: The following steps are also included: The mixing and foaming process of each raw material is stirred at a speed of 500-1000 rpm for 3-5 minutes; After hot pressing and molding in the mold, the yellowing-resistant bra cotton is post-treated, and the post-treatment includes heat treatment at 40-60° C. for 2-4 hours and placing in a ventilated environment for 12-24 hours.

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