A mop cotton hydrophilic polyurethane material and a preparation method thereof

Abstract

The application discloses a mop cotton hydrophilic polyurethane material and a preparation method thereof. The hydrophilic polyurethane material is prepared by mixing and foaming a water polyurethane prepolymer and a functional water phase mixture at a ratio of 0.6:1-2.5:1. The hydrophilic polyurethane material solves the problems of weak tearing strength, slow water absorption rate, large wet / dry volume ratio, water absorption amount and the like of the polyurethane hydrophilic cotton in the field of mops.

Description

Technical Field

[0001] This invention belongs to the field of daily chemical products technology, specifically relating to a hydrophilic polyurethane material for mop cotton and its preparation method. Background Technology

[0002] Sponge mops primarily use PVA (polyvinyl alcohol) sponges as their cleaning heads. Due to their superior absorbency—ten times that of ordinary sponges—they are easy to use; simply soak the sponge in water and pull the handle a few times to drain the wastewater. PVA mop heads are widely suitable for cleaning surfaces such as wooden floors, waterproof floors, tiled walls, marble, and glass. Besides floors, these mops can also be used to clean walls and ceilings. However, PVA sponge heads have drawbacks, including poor hair absorption, unsuitability for cleaning grease and chemical stains, and the need for prolonged soaking after natural drying, leading to inconvenience.

[0003] Hydrophilic polyurethane materials can effectively solve the problem of sponge hardening after natural drying. However, the application of hydrophilic polyurethane sponges in the mop industry to replace PVA products has not yet been commercialized on a large scale. This is mainly because the performance requirements of hydrophilic polyurethane sponges in terms of tear strength, water absorption rate, water absorption speed, and wet / dry volume shrinkage ratio have not yet met industrial requirements.

[0004] Patent US215078151 U describes a novel sponge mop head designed using hydrophilic polyurethane material. This patent details the mop head's structural design and the use of polyurethane sponge as the hydrophilic sponge. However, the patent does not explain how to prepare the hydrophilic polyurethane sponge material suitable for mop performance; it remains at the design stage and does not clearly describe the performance requirements of the polyurethane material. Several practical issues remain to be overcome before commercialization. Summary of the Invention

[0005] To address the shortcomings of hydrophilic polyurethane materials in mop applications, such as poor water absorption, slow water absorption rate, poor tear strength, and large wet / dry volume shrinkage ratio, this invention provides a hydrophilic polyurethane material for mop cotton.

[0006] Another objective of this invention is to provide a method for preparing hydrophilic polyurethane material for mop cotton. This method has a simple preparation process, is easy to operate, has stable quality, high production efficiency, low production cost, and can be industrialized for large-scale production.

[0007] The technical solution implemented by this invention is as follows:

[0008] A hydrophilic polyurethane material for mop cotton, comprising the following raw materials:

[0009] 0.6-2.5 parts by weight of hydrophilic polyurethane prepolymer

[0010] 1 part by mass of functional aqueous phase.

[0011] The hydrophilic polyurethane prepolymer is an isocyanate-terminated hydrophilic polyurethane prepolymer, which is a prepolymer prepared by reacting polyisocyanate with polyol.

[0012] Preferably, the polyisocyanate may be one or more of TDI, MDI, HMDI, and IPDI.

[0013] Preferably, the polyol is polyethylene glycol, with a molecular weight preferably between 400 and 3000, and the NCO range of the hydrophilic polyurethane prepolymer is 5.5% to 10.0%.

[0014] Preferably, a crosslinking agent is added during the preparation of the prepolymer. The crosslinking agent is a small molecule alcohol, including one or more of trimethylolpropane, glycerol, triethylene glycol, sorbitol, and 1,4-butanediol, with trimethylolpropane being preferred.

[0015] The hydrophilic polyurethane prepolymer is preferably one or more of WanSponge GST, WanSponge WDT, WanSponge FPT, Kejuya F1-F9, and Dow HYPOL JT6000. The resulting hydrophilic polyurethane material has the characteristics of good hydrophilicity and good resilience.

[0016] The functional aqueous phase comprises the following components in the indicated mass amounts:

[0017]

[0018] Based on the total mass of the above components being 100%.

[0019] The functional aqueous phase of this invention produces a hydrophilic polyurethane material with excellent properties, including high tear strength, fast water absorption rate, large water absorption ratio, and low wet / dry shrinkage ratio.

[0020] The emulsified wax is one or more of C16-18 alcohol or PEG-20 cetearyl alcohol ether, such as BASF Emulgade 1000NI;

[0021] The pore-opening agent is one or more of the following: open-cell silicone oil or block polyether surfactant, such as one or more of BASF F68, BASF F88, Dow Corning L580, and Dow Corning L603.

[0022] The foam stabilizer is a PO-EO block polyether surfactant foam stabilizer, such as BASF PL6200;

[0023] The coupling agent is an organosilicon coupling agent, such as Wacker 1120;

[0024] The functional filler is a styrene-acrylic acid copolymer hollow microsphere, such as Wanhua H400. As an organic solid filler, it is added to the hydrophilic polyurethane material of mop cotton to produce a hydrophilic polyurethane sponge with high hydrogen bond density, high tear strength, fast water absorption due to capillary action formed by the hollow microspheres, and reduced wet / dry expansion ratio when filled with sponge.

[0025] The preparation method of the functional aqueous phase is as follows: dissolve the emulsified wax in 8 to 10 parts by weight of hot water (85℃ to 100℃), mix the remaining components in proportion, pour the dissolved emulsified wax into the mixture of the remaining components, and stir evenly to obtain the functional aqueous phase.

[0026] Another objective of this invention is to provide a method for preparing the hydrophilic polyurethane material for mop cotton, wherein a hydrophilic polyurethane prepolymer and a functional aqueous phase are mixed and foamed in a mass ratio of 0.6:1 to 2.5:1, and then demolded and dried.

[0027] Preferably, the temperature of the functional aqueous phase is 8–15°C, the temperature of the hydrophilic polyurethane prepolymer (component B) is 27–35°C, and after mixing, the mixture is stirred at 3000–8000 r / min for 10–15 s, and then reacted at room temperature.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] The hydrophilic polyurethane mop cotton material prepared by this invention, due to the filling of styrene-acrylic hollow microspheres, enhances the density of hydrogen bonds between molecules and increases tear strength. The hollow microsphere filling replaces inorganic powder filling, expanding the water absorption space and increasing water absorption capacity. The hollow microspheres also possess capillary action, accelerating the water absorption rate. The hydrophilic polyurethane mop cotton material of this invention does not harden after drying, affecting consumer use and providing convenience. This hydrophilic polyurethane material has strong hydrophilicity, making it easy to clean surface dirt after wetting. Simultaneously, the material has a certain degree of oleophilicity, exhibiting excellent cleaning power for oil-soluble dirt as well. The preparation process of the hydrophilic polyurethane mop cotton material in this invention is simple, environmentally friendly, produces no byproducts, and is highly operable. Detailed Implementation

[0030] The present invention will be further illustrated below with specific embodiments, but the present invention is not limited to the listed embodiments, and should also include any other known modifications within the scope of the claims of the present invention.

[0031] Raw materials used in the examples and comparative examples:

[0032] Emulgade 1000NI (BASF emulsified wax);

[0033] PL6200 (BASF foam stabilizer);

[0034] F68 (BASF pore-opening agent);

[0035] L603 (Dow Corning Pore-Opening Silicone Oil)

[0036] 1120 (Wacker Silane Coupling Agent)

[0037] Wollastonite powder (Tiantai);

[0038] H400 hollow microspheres (Wanhua Chemical Group Co., Ltd.);

[0039] Wangsponge GST (Wanhua Chemical Group Co., Ltd.);

[0040] Example:

[0041] The formula is shown in the table below (parts by weight), and its preparation method includes the following steps:

[0042] Preparation of functional aqueous phase mixture (component A): The weighed emulsified wax was dissolved in 10 parts by weight of hot water (85℃) for 20 minutes. The remaining components were mixed in proportion. The dissolved emulsified wax was then poured into the mixture and stirred for 30 minutes to obtain functional aqueous phase mixture (component A). Component A with different component contents was prepared according to Table 1, where the content of each component is a mass fraction.

[0043] Table 1: Functional Aqueous Mixtures (Component A)

[0044] Raw materials (mass fraction) Component A 1 Component A 2 Component A 3 Component A 4 Group A 5 Group A 6 Component A 7 Group A 8 1000Ni emulsified wax 0.8 0.8. 0.8 0.1 1.8 1.8 0.8 0.8 Opening agent F68 0.5 0.3 0.8 0.3 0.3 0.5 0.5 0.5 Foam stabilizer L6200 2.0 3.5 1.2 1.2 3.5 3.5 2.0 2.0 Functional filler H400 30 5 15 60 20 30 Inorganic filler wollastonite 30 Coupling agent 1120 0.3 0.3 0.5 0.5 0.1 0.5 0.3 0.3 Deionized water margin margin margin margin margin margin margin margin

[0045] Preparation of hydrophilic polyurethane materials: Hydrophilic polyurethane prepolymer (component B) and a functional aqueous phase mixture (component A) are mixed at a ratio of 0.6:1 to 2.5:1. The temperature of component A is 8–15℃, and that of component B is 27–35℃. The mixture is stirred at 3000–8000 r / min for 10–15 s and reacted at room temperature to prepare the hydrophilic polyurethane material. Specific reaction conditions are as follows:

[0046] Example 1:

[0047] The hydrophilic polyurethane prepolymer Wansponge GST and the functional aqueous mixture (A1) were fed at a ratio of 1.6:1. The temperature of component A was 10℃ and component B was 30℃. The mixture was dispersed at a speed of 5000 r / min for 13 seconds and reacted at room temperature to obtain the hydrophilic polyurethane material. After drying, the material was cut and tested.

[0048] Example 2:

[0049] The hydrophilic polyurethane prepolymer Wansponge GST and the functional aqueous mixture (A1) were fed at a ratio of 2.2:1. The temperature of component A was 10℃ and that of component B was 30℃. The mixture was dispersed at a speed of 8000 r / min for 13 seconds and reacted at room temperature to obtain the hydrophilic polyurethane material. After drying, the material was cut and tested.

[0050] Example 3:

[0051] The hydrophilic polyurethane prepolymer Wansponge GST and the functional aqueous mixture (A2) were fed at a ratio of 1:1.6. The temperature of component A was 10℃ and component B was 30℃. The mixture was dispersed at a speed of 5000 r / min for 13 seconds and reacted at room temperature to obtain the hydrophilic polyurethane material. After drying, the material was cut and tested.

[0052] Example 4:

[0053] The hydrophilic polyurethane prepolymer Wansponge GST and the functional aqueous mixture (A3) were fed at a ratio of 1.8:1. The temperature of component A was 10℃ and component B was 30℃. The mixture was dispersed at a speed of 5000 r / min for 13 seconds and reacted at room temperature to obtain the hydrophilic polyurethane material. After drying, the material was cut and tested.

[0054] Example 5:

[0055] The hydrophilic polyurethane prepolymer Wansponge GST and the functional aqueous mixture (A4) were fed at a ratio of 2:1. The temperature of component A was 10℃ and component B was 30℃. The mixture was dispersed at a speed of 5000 r / min for 13 seconds and reacted at room temperature to obtain the hydrophilic polyurethane material. After drying, the material was cut and tested.

[0056] Example 6:

[0057] The hydrophilic polyurethane prepolymer Wansponge GST and the functional aqueous mixture (A4) were fed at a ratio of 1.6:1. The temperature of component A was 10℃ and component B was 30℃. The mixture was dispersed at a speed of 5000 r / min for 13 seconds and reacted at room temperature to obtain the hydrophilic polyurethane material. After drying, the material was cut and tested.

[0058] Example 7:

[0059] The hydrophilic polyurethane prepolymer Wansponge GST and the functional aqueous mixture (A5) were fed at a ratio of 1.6:1. The temperature of component A was 10℃ and component B was 30℃. The mixture was dispersed at a speed of 5000 r / min for 13 seconds and reacted at room temperature to obtain the hydrophilic polyurethane material. After drying, the material was cut and tested.

[0060] Example 8:

[0061] The hydrophilic polyurethane prepolymer Wansponge GST and the functional aqueous phase mixture (A6) were fed at a ratio of 1.6:1. The temperature of component A was 10℃ and component B was 30℃. The mixture was dispersed at a speed of 5000 r / min for 13 seconds and reacted at room temperature to obtain the hydrophilic polyurethane material. After drying, the material was cut and tested.

[0062] Comparative Example 1:

[0063] The hydrophilic polyurethane prepolymer Wansponge GST and the functional aqueous mixture (A7) were fed at a ratio of 1.6:1. The temperature of component A was 10℃ and that of component B was 30℃. The mixture was dispersed at a speed of 5000 r / min for 13 seconds and reacted at room temperature to obtain the hydrophilic polyurethane material. After drying, the material was cut and tested.

[0064] Comparative Example 2:

[0065] The hydrophilic polyurethane prepolymer Wansponge GST and the functional aqueous mixture (A8) were fed at a ratio of 1.6:1. The temperature of component A was 10℃ and component B was 30℃. The mixture was dispersed at a speed of 5000 r / min for 13 seconds and reacted at room temperature to obtain the hydrophilic polyurethane material. After drying, the material was cut and tested.

[0066] Comparative Example 3:

[0067] A commercially available PVA mop sponge (Sorbonne 38c) was used for comparison with a hydrophilic polyurethane sponge material. Its physical properties were measured using the same method as in the examples, and the results are shown in Table 2.

[0068] Test method:

[0069] Mechanical properties (tensile strength and elongation at break)

[0070] The mechanical properties of hydrophilic polyurethane foam materials were determined using a tensile testing machine (GOTECH TCS-2000) according to JIS-6401.

[0071] B. Water absorption rate

[0072] After measuring the initial weight (G1) of a hydrophilic polyurethane material sample with dimensions of 5cm × 5cm × 3cm, the sample was immersed in distilled water at 25°C for 1 hour. It was then removed from the distilled water, wiped with lint-free paper to remove surface water, and weighed again (G2). The absorbency of the hydrophilic polyurethane foam sample was then calculated using Equation 1 below:

[0073] Water absorption rate (%) = (G2 - G1) / G1 × 100 Equation 1

[0074] C. Absorption rate

[0075] After water droplets are placed onto the sample surface using a pipette, the time required for the water droplets to be completely absorbed into the sample is measured. This process is repeated 10 times, and the average of the 10 measurements is defined as the absorption rate of the hydrophilic polyurethane material sample.

[0076] D. Wet / Dry shrinkage rate

[0077] Take a sample of hydrophilic polyurethane material, approximately 10cm in length, as C1. Immerse it in distilled water and squeeze it 5 times. After removing it, measure the length of the hydrophilic polyurethane material sample as C2. Then, calculate its wet / dry shrinkage rate according to Formula 2:

[0078] Wet / Dry Shrinkage Rate (%) = (C2 - C1) / C1 × 100 (Formula 2)

[0079] Table 2. Physical properties of hydrophilic polyurethane materials

[0080] Tension (N) Elongation at break (%) Water absorption rate (%) Absorption rate (s) Wet / Dry shrinkage rate (%) Example 1 28.6 280 589 3.2 1.7 Example 2 30.1 285 597 3.6 1.8 Example 3 7.3 177 585 5.8 2.0 Example 4 18.4 189 590 4.2 1.9 Example 5 26.7 255 549 3.3 1.7 Example 6 34.8 298 575 2.7 1.5 Example 7 23.7 246 598 3.4 1.8 Example 8 25.3 255 587 3.6 1.7 Comparative Example 1 3.8 133 351 8.5 1.7 Comparative Example 2 5.3 156 600 6.8 2.1 Comparative Example 3 26.6 210 474 3.3 1.7

[0081] As shown in Table 1, in Examples 1, 3, 4, 6, and 7, the tear strength of the hydrophilic polyurethane material increases with the increase of the amount of functional filler H400. This is because the hydroxyl groups in the styrene-acrylic acid structure of H400 can form hydrogen bonds with the polyether in the hydrophilic polyurethane material, increasing the hydrogen bond density in the material and thus enhancing the tear strength. With the increase of functional filler H400, the water absorption rate of the hydrophilic polyurethane material increases, while the water absorption decreases slightly. This is because H400 has a hollow structure and has a capillary effect with the pores in the hydrophilic polyurethane material, thereby enhancing the water absorption rate of the hydrophilic polyurethane material. However, the water absorption is reduced because the filler occupies space, but this does not affect the use of the product. With the increase of functional filler H400, the wet / dry shrinkage ratio of the hydrophilic polyurethane material gradually decreases. This is because the increase of H400 filler reduces the expansion coefficient of the hydrophilic segments in the hydrophilic polyurethane material.

[0082] As can be seen from Comparative Example 1, Comparative Example 2, and Comparative Example 3, when no functional filler is added to component A, the tensile strength wet / wet shrinkage ratio of the hydrophilic polyurethane material is relatively large (the lower the better), and the tensile strength is far less than that of the PVA sponge in Comparative Example 3, which cannot meet the requirements of practical applications. At the same time, when traditional wollastonite fillers are added to component A, the establishment of hydrogen bonds between products is further disrupted, resulting in poorer tear strength of the hydrophilic polyurethane material. Furthermore, the wollastonite filler occupies space in the hydrophilic polyurethane sponge material, reducing the water absorption rate and water absorption capacity.

Claims

1. The application of a hydrophilic polyurethane material in mop cotton, characterized in that, The hydrophilic polyurethane material comprises the following raw materials: 0.6-2.5 parts by weight of hydrophilic polyurethane prepolymer 1 part by mass of functional aqueous phase; The hydrophilic polyurethane prepolymer is an isocyanate-terminated hydrophilic polyurethane prepolymer, which is a prepolymer prepared by reacting polyisocyanate with polyol. The functional aqueous phase comprises the following components in the indicated mass amounts: Emulsified wax 0.1%~1.8%; 0.1-1.5% pore-opening agent; Foam stabilizer 1.0~5.0%; Coupling agent 0.1~0.5%; Functional fillers: 5%–60%; Deionized water balance; Based on the total mass of the above components being 100%; The functional filler is a styrene-acrylic acid copolymer hollow microsphere.

2. The application according to claim 1, characterized in that, The polyisocyanate is one or more of TDI, MDI, HMDI, and IPDI.

3. The application according to claim 1, characterized in that, The polyol is polyethylene glycol with a molecular weight of 400-3000, and the NCO range of the hydrophilic polyurethane prepolymer is 5.5%-10.0%.

4. The application according to claim 1, characterized in that, The prepolymer preparation process also includes the addition of a crosslinking agent, which is a small molecule alcohol, including one or more of trimethylolpropane, glycerol, triethylene glycol, sorbitol, and 1,4-butanediol.

5. The application according to claim 4, characterized in that, The crosslinking agent is trimethylolpropane.

6. The application according to claim 1, characterized in that, The functional aqueous phase comprises the following components in the indicated mass amounts: Emulsified wax 0.5%~1.2%; 0.1%~0.6% pore-opening agent; Foam stabilizer 1.0%~3.0%; Coupling agent 0.1%~0.3%; Functional fillers: 20%–45%; Deionized water balance; Based on the total mass of the above components being 100%.

7. The application according to claim 1, characterized in that, The emulsified wax is one or more of C16-18 alcohol or PEG-20 cetearyl alcohol ether; The pore-opening agent is one or more of pore-opening silicone oil or block polyether surfactant; The foam stabilizer is a PO-EO block polyether surfactant foam stabilizer. The coupling agent is an organosilicon coupling agent.

8. The application according to claim 1, characterized in that, The preparation method of the functional aqueous phase is as follows: dissolve the emulsified wax in 8 to 10 parts by weight of hot water, mix the remaining components in proportion, pour the dissolved emulsified wax into the mixture of the remaining components, and stir evenly to obtain the functional aqueous phase.

9. The application according to claim 1, characterized in that, The hydrophilic polyurethane material is prepared by mixing hydrophilic polyurethane prepolymer and functional aqueous phase in a mass ratio of 0.6:1 to 2.5:1, foaming, demolding and drying.

10. The application according to claim 9, characterized in that, The temperature of the functional aqueous phase is 8~15℃, and the temperature of the hydrophilic polyurethane prepolymer is 27~35℃. After mixing, the mixture is stirred at 3000~8000r / min for 10~15s, and then reacted at room temperature.

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