A high resilience mattress sponge and method of making same

Abstract

The application belongs to the technical field of polyurethane sponge and specifically relates to a high-resilience sponge for mattresses and a preparation method thereof; the high-resilience sponge for mattresses comprises components A and B in a mass ratio of 100:40-60; the component A comprises, in mass parts, 100 parts of polyol, 2-5 parts of foaming agent, 0.1-0.5 parts of catalyst and 0.3-1 parts of foam stabilizer; the polyol comprises polyether polyol, polymer polyol and cashew nut shell oil phenol-formaldehyde resin polyol in a mass ratio of 6-8:1-2:0.1-0.2; the component B comprises modified isocyanate; the modified isocyanate is a mixture of polyol-modified diphenylmethane diisocyanate and polymethylene polyphenyl isocyanate. The sponge for mattresses provided by the application has high resilience and also has excellent support, durability and aging resistance.

Description

Technical Field

[0001] This invention belongs to the field of polyurethane foam technology, specifically relating to a high-resilience mattress foam and its preparation method. Background Technology

[0002] Mattresses are essential furniture items in people's daily lives, playing a vital role in providing sleep comfort and support. Currently, common mattress materials mainly include polyurethane foam, latex, and memory foam, with polyurethane foam being widely used due to its low production cost, softness, and good elasticity.

[0003] Resilience is one of the key indicators of mattress foam. However, high-quality high-resilience mattress foam does not only depend on a high resilience rate. Its mechanical properties and aging performance are equally important.

[0004] Chinese patent CN 119751814 A discloses a tough sponge, its preparation method, and its application. The raw materials, by mass percentage, include: polyol, 100 parts; isocyanate, index 0.85-1.05; amine catalyst, 0.2-0.6 parts; metal catalyst, 0.05-0.3 parts; silicone foam stabilizer, 0.3-1.5 parts; water, 1.2-4.5 parts; and tensile agent, 0.8-3 parts. The polyether polyol has a hydroxyl value of 20-80. The sponge exhibits good breaking and tensile properties; however, the indentation hardness of this technology only reaches approximately 65 N, indicating that its support properties need improvement.

[0005] Chinese patent CN118978664A discloses a high-resilience sponge material and its preparation method. This technology uses polyester polyol block prepolymer and 1,4-butanediisocyanate as raw materials to prepare a self-made polyurethane, which is then used as a raw material to produce a sponge material through foaming. The polyester polyol block prepolymer, as a polymer compound, contains multiple hydroxyl functional groups in its molecular structure, which can react with 1,4-butanediisocyanate to generate polyurethane. This reaction can form a cross-linked structure between polymer chains, giving the polyurethane sponge material higher elasticity and resilience. After being compressed by external force, the polyurethane sponge material can quickly return to its original shape and volume, exhibiting excellent resilience. This high resilience allows the polyurethane sponge material to provide better support and comfort in applications such as cushions and mattresses. However, the tensile strength of this technology only reaches 95 kPa, and its durability needs improvement. Furthermore, none of the above-mentioned prior art addresses the aging performance of the sponge. Summary of the Invention

[0006] The present invention aims to solve one or more technical problems existing in the prior art, and at least provide a beneficial solution. Specifically, the present invention provides a high-resilience mattress sponge and a method for preparing the same, which has high resilience as well as excellent support, durability and aging resistance.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] In a first aspect, the present invention provides a high-resilience mattress sponge, comprising component A and component B in a mass ratio of 100:40-60; wherein component A, by mass parts, comprises 100 parts of polyol, 2-5 parts of foaming agent, 0.1-0.5 parts of catalyst, and 0.3-1 parts of foam stabilizer;

[0009] The polyols include polyether polyols, polymer polyols, and cashew nut shell oil phenolic resin polyols in a mass ratio of 7.8-8.9:1-2:0.1-0.2.

[0010] Component B includes a modified isocyanate; the modified isocyanate is a mixture of polyol-modified diphenylmethane diisocyanate and polymethylene polyphenyl isocyanate.

[0011] Preferably, the hydroxyl value of the polyether polyol is 46-58 mgKOH / g, which can be any one value or a range of any two values ​​among 46 mgKOH / g, 48 mgKOH / g, 50 mgKOH / g, 53 mgKOH / g, 54 mgKOH / g, 56 mgKOH / g, and 58 mgKOH / g.

[0012] Preferably, the polyether polyols include CHE-5602, CHE-5603 and CHP-335 from Changxing Chemical.

[0013] More preferably, the polyether polyol has a hydroxyl value of 54-58 mgKOH / g and is CHE-5602 from Changxing Chemical.

[0014] Preferably, the polymer polyol has a solid content of ≥40%, a hydroxyl value of 17-25 mgKOH / g, an acrylonitrile residue of ≤2 mg / kg, and a styrene residue of ≤10 mg / kg.

[0015] Compared with existing technologies, this invention screens the types and proportions of polyols and modified isocyanates to obtain mattress sponges that have good resilience performance, a moderate 65% / 25% indentation ratio, a high 25% hardness and tensile strength, i.e., good support and durability. In addition, the low-temperature flexibility of the polyether polyol, the rigid particles in the polymer polyol, and the high functionality and hydrolytic stability of the cashew nut shell oil phenolic resin polyol, combined with the modified isocyanate, result in mattress sponges that also have excellent resistance to damp heat aging and low-temperature resistance.

[0016] The inventors discovered that using polymer polyols with a solid content ≥40%, a hydroxyl value of 17-25 mgKOH / g, acrylonitrile residue ≤2 mg / kg, and styrene residue ≤10 mg / kg can improve the resilience of mattress foam, reduce the 40% indentation hardness loss value after repeated indentation fatigue under constant load, increase hardness by 25%, increase tensile strength, and improve damp heat aging performance and low temperature resistance.

[0017] Preferably, the polymeric polyols include CHP-H45D and CHP-H45C from Changxing Chemical.

[0018] More preferably, the polymer polyol has a solid content of 41-45%, a hydroxyl value of 19-23 mgKOH / g, an acrylonitrile residue of ≤2 mg / kg, and a styrene residue of ≤10 mg / kg, and is CHP-H45D from Changxing Chemical.

[0019] Preferably, the cashew nut shell oil phenolic resin polyol has a hydroxyl value of 130-190 mgKOH / g and an average hydroxyl functional group of 3.5-4.5.

[0020] Preferably, the cashew nut shell oil phenolic resin polyols include Cardell's LITE 9001, NX-9001, and NX-9001LV.

[0021] More preferably, the cashew nut shell oil phenolic resin polyol has a hydroxyl value of 175 mg KOH / g and an average hydroxyl functional group of 4.3, and is Cardlä's NX-9001.

[0022] In the above technical solution, the weight of the foaming agent can be any one value or a range of any two values, such as 2 parts, 3 parts, 4 parts, or 5 parts.

[0023] In the above technical solution, preferably, the foaming agent is water.

[0024] In the above technical solution, the weight parts of the catalyst can be any one value or a range of any two values ​​from 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, and 0.5 parts.

[0025] In the above technical solution, preferably, the catalyst comprises an amine catalyst and a triazine catalyst in a mass ratio of 2-4:1.

[0026] Preferably, the amine catalyst is selected from at least one of pentamethyldipropylenetriamine and triethylenediamine.

[0027] Preferably, the triazine catalyst is 1,3,5-tris(dimethylaminopropyl)hexahydrotriazine.

[0028] In the above technical solution, the weight parts of the foam stabilizer can be any one value or a range of any two values ​​from 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, and 1 part.

[0029] In the above technical solution, preferably, the foam stabilizer includes non-hydrolyzed silicone oil, dimethylsiloxane-polyoxyolefin copolymer and polysiloxane-polyepoxyalkane-block copolymer in a mass ratio of 2-4:0.3-0.6:0.4-0.7.

[0030] Preferably, the viscosity of the non-hydrolyzed silicone oil is 100-400 cst (25°C).

[0031] Preferably, the non-hydrolyzed silicone oils include BL-8036, BL-8333, and BL-8309H from Maihao Technology.

[0032] Preferably, the viscosity of the non-hydrolyzed silicone oil is 200-400 cst (25°C), and it is BL-8333 from Maihao Technology.

[0033] Preferably, the dimethylsiloxane-polyoxyolefin copolymer is Stey Chemicals' Silstab 3000.

[0034] Preferably, the polysiloxane-polyepoxyane-block copolymer is Evonik's TEGOSTAB B8002.

[0035] Compared with the prior art, the present invention also screened the types of foam stabilizers and found that when the foam stabilizer includes non-hydrolyzed silicone oil, dimethylsiloxane-polyoxyolefin copolymer and polysiloxane-polyepoxyane-block copolymer in a mass ratio of 2-4:0.3-0.6:0.4-0.7, the cell size distribution is more uniform and the shear resistance of the cell wall is improved. Therefore, it reduces the 40% indentation hardness loss value after repeated indentation fatigue under constant load of mattress foam, and increases the hardness and tensile strength by 25%.

[0036] In the above technical solution, preferably, the NCO content of the modified isocyanate is 26-31%.

[0037] The second aspect of the present invention provides a method for preparing the above-mentioned high-resilience mattress sponge, comprising the following steps: first, mixing polyol, foaming agent, catalyst and foam stabilizer evenly to obtain component A; placing component A and component B in a mold, foaming and maturing to obtain the final product.

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] 1. This invention selects polyether polyol, polymer polyol and cashew nut shell oil phenolic resin polyol in a mass ratio of 7.8-8.9:1-2:0.1-0.2 as polyols; and a mixture of polyol-modified diphenylmethane diisocyanate and polymethylene polyphenyl isocyanate as modified isocyanate. The resulting mattress sponge has good resilience (resilience rate of about 48%), excellent support performance (moderate 65% / 25% indentation ratio (about 2.4), high 25% hardness (about 152N)), durability (tensile strength (about 142N)), and excellent resistance to damp heat aging and low temperature (no obvious cracks at -24℃).

[0040] 2. The present invention uses polymer polyols with a solid content ≥40%, a hydroxyl value of 17-25 mgKOH / g, acrylonitrile residue ≤2 mg / kg, and styrene residue ≤10 mg / kg, which can improve the resilience of mattress foam, reduce the 40% indentation hardness loss value after repeated indentation fatigue under constant load, increase hardness by 25%, increase tensile strength, and improve damp heat aging performance and low temperature resistance.

[0041] 3. The foam stabilizer of the present invention comprises non-hydrolyzed silicone oil, dimethylsiloxane-polyoxyolefin copolymer and polysiloxane-polyepoxyalkylene-block copolymer in a mass ratio of 2-4:0.3-0.6:0.4-0.7, which can reduce the indentation hardness loss value of mattress foam after repeated indentation fatigue under constant load by 40%, increase hardness by 25%, and increase tensile strength.

[0042] 4. The high-resilience mattress sponge provided by this invention is formaldehyde-free and odorless. Attached Figure Description

[0043] Figure 1 This is a photograph of the mattress foam from Example 1;

[0044] Figure 2 This is a photograph of the mattress foam from Example 2;

[0045] Figure 3 Infrared spectrum of the mattress foam used in Example 1 for material analysis;

[0046] Figure 4The graph shows the test results of formaldehyde content, pH, odor, and physical properties of the mattress sponge in Example 1. Detailed Implementation

[0047] The technical solution of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention. Experimental or testing methods not specified in the following embodiments of the present invention are conventional methods in the art unless otherwise specified.

[0048] Table 1

[0049]

[0050] Examples 1-2 and Comparative Examples 1-4 provide a high-resilience mattress sponge composed of component A and component B in a mass ratio of 100:50;

[0051] The composition of component A, by mass, is shown in Table 2.

[0052] Component B is modified isocyanate A.

[0053] Table 2

[0054]

[0055] The preparation method of the above-mentioned high-resilience mattress sponge is as follows: First, the polyol, foaming agent, catalyst and foam stabilizer are mixed evenly to obtain component A; then component A and component B are placed in a mold, foamed, and cured at room temperature for 24 hours to obtain the final product.

[0056] Actual pictures of the mattress foam in Examples 1 and 2 are shown below. Figure 1 and Figure 2 As shown.

[0057] Comparative Example 5 provides a high-resilience mattress sponge, which differs from Example 1 only in that modified isocyanate A is replaced with modified isocyanate B; all other aspects are the same.

[0058] Test Example 1:

[0059] The mattress foams of Example 1 and Comparative Examples 1-5 were tested according to GB / T 10802-2023 standard. The test items and results are shown in Table 3.

[0060] Table 3

[0061] Rebound rate, % 40% indentation hardness loss (P) after repeated indentation fatigue under constant load, % 65% / 25% indentation ratio 25% hardness, N Tensile strength, kPa Change rate of tensile strength after damp heat aging, % Low temperature resistance (freezing at -20℃ for 24 hours) Example 1 48 22 2.4 151 142 -3.8 No visible cracks Example 2 46 23 2.5 155 145 -4.1 No visible cracks Comparative Example 1 41 31 2.0 136 120 -5.9 Visible cracks appear Comparative Example 2 37 36 1.9 127 115 -7.6 Visible cracks appear Comparative Example 3 35 40 1.7 125 107 -7.1 Visible cracks appear Comparative Example 4 42 29 2.3 139 128 -4.5 No cracks Comparative Example 5 39 27 2.0 141 130 -8.1 Visible cracks appear

[0062] As can be seen from Table 3, compared with Comparative Example 1, without cashew nut shell oil phenolic resin polyol, the 40% indentation hardness loss value of the obtained mattress sponge after constant load repeated indentation fatigue was significantly reduced, the 25% hardness was significantly reduced, the tensile strength was significantly reduced, and visible cracks appeared after freezing at -20℃ for 24 hours.

[0063] Compared with Comparative Examples 2, 3, and 5, and Example 1, specific polymer polyols and specific modified isocyanates can improve the resilience of mattress foam, reduce the 40% indentation hardness loss value after repeated indentation fatigue under constant load, increase hardness by 25%, increase tensile strength, and improve damp heat aging performance and low temperature resistance.

[0064] Compared with Example 1, the specific compounded foam stabilizer can reduce the indentation hardness loss value of mattress foam after repeated indentation fatigue under constant load by 40%, and increase the hardness and tensile strength by 25%.

[0065] The mattress foams in Examples 1 and 2 have a high resilience rate, a moderate 65% / 25% indentation ratio, a high 25% hardness, and tensile strength, indicating good support; they also have excellent damp heat aging performance and low temperature resistance.

[0066] Test Example 2

[0067] In Example 1, a sample of mattress foam was sent for testing to determine formaldehyde content, pH, material analysis, odor, and physical properties. The results are as follows: Figures 3-4 As shown.

[0068] Depend on Figure 4 It can be seen that the mattress sponge of Embodiment 1 of the present invention is formaldehyde-free and odorless, and also has good dry heat aging performance and tear strength.

[0069] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, and is not intended to limit the scope of protection of the present invention. Simple modifications or equivalent substitutions made by those skilled in the art to the technical solution of the present invention do not depart from the essence and scope of the technical solution of the present invention.

Claims

1. A high-resilience mattress sponge, characterized in that, It includes component A and component B in a mass ratio of 100:40-60; component A, by mass, includes 100 parts of polyol, 2-5 parts of foaming agent, 0.1-0.5 parts of catalyst, and 0.3-1 parts of foam stabilizer; The polyol comprises polyether polyol, polymer polyol and cashew nut shell oil phenolic resin polyol in a mass ratio of 7.8-8.9:1-2:0.1-0.2; the B component comprises modified isocyanate. The modified isocyanate is a mixture of polyol-modified diphenylmethane diisocyanate and polymethylene polyphenyl isocyanate; The polymer polyol has a solid content of ≥40%, a hydroxyl value of 17-25 mgKOH / g, an acrylonitrile residue of ≤2 mg / kg, and a styrene residue of ≤10 mg / kg; The foam stabilizer comprises non-hydrolyzed silicone oil, dimethylsiloxane-polyoxyolefin copolymer, and polysiloxane-polyepoxyalkane-block copolymer in a mass ratio of 2-4:0.3-0.6:0.4-0.

7.

2. The high-resilience mattress foam according to claim 1, characterized in that, The hydroxyl value of the polyether polyol is 46-58 mg KOH / g.

3. The high-resilience mattress foam according to claim 1, characterized in that, The cashew nut shell oil phenolic resin polyol has a hydroxyl value of 130-190 mgKOH / g and an average hydroxyl functional group of 3.5-4.

5.

4. The high-resilience mattress sponge according to claim 1, characterized in that, The catalyst comprises an amine catalyst and a triazine catalyst in a mass ratio of 2-4:

1.

5. The high-resilience mattress foam according to claim 4, characterized in that, The amine catalyst is selected from at least one of pentamethyldipropylenetriamine and triethylenediamine; the triazine catalyst is 1,3,5-tris(dimethylaminopropyl)hexahydrotriazine.

6. The high-resilience mattress foam according to claim 1, characterized in that, The dimethylsiloxane-polyoxyolefin copolymer is Stey Chemicals' Silstab 3000.

7. The high-resilience mattress foam according to claim 1, characterized in that, The polysiloxane-polyepoxyane-block copolymer is Evonik's TEGOSTAB B8002.

8. The method for preparing the high-resilience mattress sponge according to any one of claims 1-7, characterized in that, Includes the following steps: First, mix the polyol, foaming agent, catalyst and foam stabilizer evenly to obtain component A; place component A and component B in a mold, and foam and mature to obtain the final product.

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