FLEXIBLE POLYURETHANE FOAM MATERIAL WITH STRONG SUPPORT AND HIGH ELASTICITY, AND PREPARATION METHOD THEREOF

Abstract

A flexible polyurethane foam material with strong support and high elasticity is made by foaming the following raw materials by weight: 80-120 parts of lignin-based block copolymer molecular-level combined polyether; 45-65 parts of isocyanate; 0.5-5 parts of foaming catalyst; 1-10 parts of water; and 1-3 parts of foam stabilizer; the lignin-based block copolymer molecular-level combined polyether is based on lignosulfonate, molecular chain of lignosulfonate is cut and embedded by using solvation effect of polyether polyol to form a molecular-level combined polyether that is polymerized and formed by aromatic polymer fragments of lignosulfonate and aliphatic polymer fragments of polyether polyol. The foaming catalyst can be a foaming catalyst commonly used in the technical field.

Claims

1. A flexible polyurethane foam material with strong support and high elasticity, made by foaming the following raw materials by weight: 80-120 parts of lignin-based block copolymer molecular-level combined polyether; 45-65 parts of isocyanate; 0.5-5 parts of foaming catalyst; 1-10 parts of water; and 1-3 parts of foam stabilizer; wherein the lignin-based block copolymer molecular-level combined polyether is based on lignosulfonate, a molecular chain of the lignosulfonate is cut and embedded by using solvation effect of polyether polyol to form a molecular-level combined polyether that is polymerized and formed by aromatic polymer fragments of lignosulfonate and aliphatic polymer fragments of polyether polyol, namely the lignin-based block copolymer molecular-level combined polyether.

2. The flexible polyurethane foam material with strong support and high elasticity of claim 1, wherein the lignosulfonate is one or more selected from a group consisting of sodium lignosulfonate, calcium lignosulfonate and magnesium lignosulfonate; the polyether polyol is one or two selected from a group consisting of polyethylene glycol (PEG) and polypropylene glycol (PPG); and the polyether polyol is one or more selected from a group consisting of PEG200, PEG400, PPG200 and PPG400.

3. The flexible polyurethane foam material with strong support and high elasticity of claim 1, wherein the lignin-based block copolymer molecular-level combined polyether is prepared by following steps: 1) pretreatment of lignosulfonate: mixing the lignosulfonate and a pretreatment reagent in a weight ratio of 1:(2-10), and pretreating for 60-240 minutes at a temperature of 100-140° C. and a pressure of 10-15 MPa; 2) removal of pretreatment reagent: after the pretreatment, removing the pretreatment reagent by vacuum distillation; 3) hard and soft copolymerization of lignosulfonate and polyether polyol: copolymerizing the lignosulfonate and the polyether polyol in a weight ratio of 1:(1-5), with a copolymerization temperature of 120-180° C., and time of 1-4 hours, after reaction, the lignin-based block copolymer molecular-level combined polyether is obtained.

4. The flexible polyurethane foam material with strong support and high elasticity of claim 3, wherein in the hard and soft copolymerization of step 3), sulfuric acid or phosphoric acid is used as a catalyst, and an addition amount of the catalyst is 2-7 wt % of a total weight of the lignosulfonate and the polyether polyol.

5. The flexible polyurethane foam material with strong support and high elasticity of claim 3, wherein the pretreatment reagent is one or more selected from a group consisting of methanol, ethanol, propylene glycol and 1-4 butanediol.

6. The flexible polyurethane foam material with strong support and high elasticity of claim 3, wherein in the vacuum distillation of the step 2), a process condition with a temperature of 80-120° C., a mercury column of 750-1 mm, and time of 30-120 minutes is used.

7. The flexible polyurethane foam material with strong support and high elasticity of claim 1, wherein the foaming catalyst is made by mixing A and B in a weight ratio of 1:(0.5-2), where A is triethylenediamine or bis(2-dimethylaminoethyl) ether, and B is stannous octoate.

8. The flexible polyurethane foam material with strong support and high elasticity of claim 1, wherein the foam stabilizer is a silicone foam stabilizer.

9. The flexible polyurethane foam material with strong support and high elasticity of claim 1, wherein the flexible polyurethane foam material is made by foaming the following raw materials by weight: 100 parts of lignin-based block copolymer molecular-level combined polyether; 50-55 parts of isocyanate; 0.75-2 parts of foaming catalyst; 2-3 parts of water; and 1-3 parts of foam stabilizer.

10. A preparation method of the flexible polyurethane foam material with strong support and high elasticity of claim 1, comprising the following steps: materials preparation: preparing materials according to a formula of raw materials; and foaming: mixing and stirring uniformly in a high-speed mixer, and foaming at a material temperature of 15-30° C. for 30-180 seconds to obtain the flexible polyurethane foam material.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to explain the embodiments of the present invention or the technical solutions of the prior art more clearly, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are merely for some of the embodiments of the present invention, those ordinarily skilled in the art can obtain other drawings based on these drawings without creative work. In such drawings:

[0035] FIG. 1 is a process flow diagram of a preparation method of molecular-level combined polyether based on lignosulfonate and a producing method of flexible polyurethane foam material according to one embodiment of the present invention;

[0036] FIG. 2 is shows one-dimensional density function curve of the flexible polyurethane foam material of the present invention; and

[0037] FIG. 3 is a structural diagram of the flexible polyurethane foam material inferred based on the SAXS chart of the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0038] The technical solutions of the present invention will be further described in detail through specific embodiments below. It should be understood that the implementation of the present invention is not limited to the following embodiments, and any modifications and/or changes made to the present invention will fall into the protection scope of the present invention.

[0039] In the present invention, unless otherwise specified, all parts and percentages are units of weight, and the equipment and raw materials used may be purchased from the market or are commonly used in the field. The methods in the following embodiments, unless otherwise specified, are conventional in the art.

[0040] The reagents used in the following embodiments, unless otherwise specified, may be purchased from conventional biochemical reagent stores. Quantitative data in the following embodiments are all set to three repeated experiments, and averaged results are collected.

[0041] Standard sample is a flexible polyurethane foam material, purchased from Zhejiang Glory Home Furnishing Co., Ltd., with a model of l3324.

Embodiment 1—Preparation of Lignin-Based Block Copolymer Molecular-Level Combined Polyether

[0042] A preparation method of lignin-based block copolymer molecular-level combined polyether includes the following steps, as shown in the flow chart in FIG. 1:

[0043] 1) pretreatment of lignosulfonate:

[0044] mixing a lignosulfonate and a pretreatment reagent in a weight ratio of 1:(2-10), and pretreating for 60-240 minutes at a temperature of 100-140° C. and a pressure of 10-15 MPa;

[0045] 2) removal of pretreatment reagent;

[0046] after the pretreatment, removing the pretreatment reagent by vacuum distillation;

[0047] 3) hard and soft copolymerization of lignosulfonate and polyether polyol:

[0048] copolymerizing the lignosulfonate and the polyether polyol in a weight ratio of 1:(1-5), with a copolymerization temperature of 120-180° C. and time of 1-4 hours, after the reaction, the lignin-based block copolymer molecular-level combined polyether is obtained.

[0049] Further, the lignosulfonate is one or more selected from a group consisting of sodium lignosulfonate, calcium lignosulfonate and magnesium lignosulfonate.

[0050] Further, the polyether polyol is one or two selected from a group consisting of of polyethylene glycol (PEG) and polypropylene glycol (PPG), and in particular is one or more selected from a group consisting of PEG200, PEG400, PPG200 and PPG400.

[0051] In the preparation method, the pretreatment reagent is one or more selected from a group consisting of methanol, ethanol, propylene glycol and 1-4 butanediol.

[0052] Further, in the vacuum distillation of the step 2), a process condition with a temperature of 80-120° C., a mercury column of 750-1 mm, and time of 30-120 minutes is used.

[0053] On the basis of Embodiment 1, the above preparation method is further improved to obtain Embodiment 2. The difference between the present embodiment and the Embodiment 1 includes that, in the hard and soft copolymerization of step 3), sulfuric acid or phosphoric acid is used as a catalyst, and an addition amount of the catalyst is 2-7 wt % of a total weight of the lignosulfonate and the polyether polyol.

[0054] On the basis of Embodiment 1, the above preparation method is further improved to obtain Embodiment 3. The difference between the present embodiment and the Embodiment 1 includes that, the pretreatment reagent is ethanol.

[0055] On the basis of Embodiment 1, the above preparation method is further improved to obtain Embodiment 4. The difference between the present embodiment and the Embodiment 1 includes that, the pretreatment reagent is propylene glycol.

[0056] On the basis of Embodiment 1, the above preparation method is further improved to obtain Embodiments 5, 6 and 7. Table 1 shows raw material proportions, reagents and specific processes of each step involved in this method.

TABLE-US-00001 TABLE 1 Embodiment 5 6 7 Step1) Methanol 100 kg 100 kg 100 kg Sodium  20 kg  50 kg  10 kg lignosulfonate Process condition Temperature: 100° C. Temperature: 120° C. Temperature: 140° C. Time: 60 minutes Time: 60 minutes Time: 120 minutes Pressure: 15 MPa Pressure: 10 MPa Pressure: 15 MPa Step 2) After pretreatment, vacuum After pretreatment, vacuum After pretreatment, vacuum distillation is performed for distillation is performed for distillation is performed for 60 minutes at a temperature 60 minutes at a temperature 60 minutes at a temperature of 100° C. to form pretreated of 100° C. to form pretreated of 100° C. to form pretreated lignosulfonate TR-lignin-1 lignosulfonate TR-lignin-2 lignosulfonate TR-lignin-3 Step 3) Lignosulfonate TR-lignin-1 100 kg TR-lignin-2 100 kg TR-lignin-3 100 kg Polyether polyol PEG200 100 kg PEG400 400 kg PPG200 200 kg Catalyst Phosphoric acid Phosphoric acid Phosphoric acid (concentration 85 wt %) (concentration 85 wt %) (concentration 85 wt %)  6 kg  20 kg  6 kg Process condition Temperature: 180° C. Temperature: 160° C. Temperature: 120° C. Time: 120 minutes Time: 180 minutes Time: 160 minutes

[0057] The lignin-based block copolymer molecular-level combined polyethers prepared by the above embodiments were tested for properties, and the results are shown in Table 2.

TABLE-US-00002 TABLE 2 Embodiment Property index 5 6 7 Color Brown Brown Light brown Viscosity (mPa .Math. s/25° C.) 3000 2000 2000 Hydroxyl value (mgKOH/g) 250 180 200 Functionality 5-8 2-3 4-6 Molecular weight 500-800 400-600 300-500 Acid value 0.2 0.3 0.3 Density (g/ml) 1.04 1.04 1.04

[0058] The factors that have a greater impact on the properties of molecular-level combined polyethers include solvent, catalysts reaction temperature, and reaction time. According to the data in Table 2, it can be proved that sulfuric acid is a better catalyst than phosphoric acid, as it can cut the molecular chain of lignin at a lower dosage; and low temperature and relatively long time are beneficial to improve the properties of the product. In summary, the properties in Embodiment 7 are better. PPG is a better solvent than PEG In practical applications, under the same ratio, the molecular-level combined polyether formed by PPG liquefaction has a lower viscosity, which is more conducive to production.

Embodiments 8-10

[0059] In a preparation method of flexible polyurethane foam material with strong support and high elasticity, the lignin-based block copolymer molecular-level combined polyether obtained from Embodiment 7 is used as raw material for preparation. The raw material formula of the flexible polyurethane foam material is shown in Table 3.

TABLE-US-00003 TABLE 3 (in kg) Emboidment 8 9 10 Lignin-based block copolymer molecular 100 100 100 molecular-level combined polyether Black material TDI 55 55 55 Water 2.0 2.0 2.0 Foam stabilizer 580 1.5 1.5 1.5 Stannous octoate 0.5 0.25 0.25 Triethylenediamine — 0.5 — Bis(2-dimethylaminoethyl) ether — — 0.5

[0060] The above-mentioned raw materials are uniformly mixed and stirred in a high-speed mixer, and foamed at a material temperature of 15-25° C. to obtain a flexible polyurethane foam material. Specifically, the black material TDI and MDI are both isocyanates. After testing, the technical indicators of the flexible polyurethane foam material are shown in Table 4. The one-dimensional density function curve of the flexible polyurethane foam material is shown in FIG. 2, and a structure diagram of the flexible polyurethane foam material inferred based on SAXS chart is shown in FIG. 3.

TABLE-US-00004 TABLE 4 Indicators Standard Embodiment Embodiment Embodiment sample (for Properties 8 9 10 comparison) Density (kg/m.sup.3) 45 45 45 45 Indentation ±10 ±10 ±10 ±13 hardness deviation (N) Rebound rate (%) ≥40 ≥42 ≥40 ≥35 75% compression ≤6 ≤5 ≤5 ≤8 set (%) 40% indentation ≤20 ≤18 ≤16 ≤30 hardness loss after constant load repeated indentation fatigue (%) Comfor factor 2.6 2.8 2.8 2.1 (65/25)

[0061] The data in Table 4 proves that, comparing with the standard sample, the flexible polyurethane foam material using lignin-based block copolymer molecular-level combined polyether has lower indentation hardness deviation (softer) and higher rebound rate (stronger support), and lower 40% indentation hardness loss after constant load repeated indentation fatigue (lifetime of strong support), therefore a higher comfort factor is achieved.

[0062] At the same time, the data in Table 3 also shows that the effect of the composite catalyst is better than that of single catalyst.

[0063] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments, and the same or similar parts among the various embodiments can be referred to each other. For the device/product disclosed in the present application, since it corresponds to the method disclosed in the embodiments, the description is relatively simple therefore, and the relevant parts can be referred to the description of the method parts.

[0064] The flexible polyurethane foam material with strong support and high elasticity and the preparation method thereof provided by the present invention are described in detail above. Specific examples are used in this article to illustrate the principle and implementation of the present invention, and the description of the above embodiments is only used to help understand the method and core idea of the present invention. It should be noted that for those ordinarily skilled in the art, without departing from the principle of the present invention, several improvements and modifications can be made to the present invention, which also fall within the protection scope of the present application defined by the appended claims.