Preparation method and application of polyurethane foam with humidity adjusting capability

Abstract

The invention discloses a preparation method and application of polyurethane foam with humidity adjusting ability, and the preparation method of the polyurethane foam with humidity adjusting ability is characterized by comprising the following preparation steps: S1, pretreatment of cow leather fibers; s2, preparing polyurethane foam with humidity adjusting capability; s21, the polyurethane foam polyol component is mixed with the polyurethane foam isocyanate component through a feeding machine; s22, coating release paper or a release film with the mixed components or injecting the mixed components into a mold; s23, high-temperature curing is conducted; and S24, stripping the release paper or the film or the mold to obtain the polyurethane foam. The antistatic property, the moisture regulation property, the flame retardance and the strength of the two-component polyurethane foam are effectively improved.

Description

Technical Field

[0001] The invention relates to the technical field of polyurethane foam, and in particular to a preparation method of polyurethane foam with humidity regulating ability and application thereof. Background Art

[0002] Two-component polyurethane (PU) foam is obtained by chemical reaction after mixing polyol component and isocyanate component. The foam cells mainly come from the carbon dioxide gas released by the reaction of water and isocyanate. By adjusting the ratio of polyol component to isocyanate component, foams of various hardness can be easily obtained, and the range of resilience and hardness can be particularly wide. Because the polyurethane material itself has the dual properties of plastic and rubber, the polyurethane foam has excellent performance, and it has the characteristics of shock absorption, sound absorption, warmth retention, and good flame retardancy. Therefore, the film-like polyurethane microporous foam is widely used in 3C, automobiles, home decoration, fashion bags and other fields.

[0003] In order to reduce costs, the PU foam industry generally adds inorganic fillers, such as calcium carbonate, talcum powder, etc.; in order to increase flame retardancy, the industry generally adds various flame retardants, such as liquid nitrogen-phosphorus flame retardants; in order to improve the antistatic properties of PU foam, the industry generally needs to add antistatic agents;

[0004] However, polyurethane foam lacks the functions of anti-static and active moisture absorption, especially the humidity regulation ability.

[0005] Cowhide fiber is a natural collagen fiber that is physically extracted from the cow split hide. Cowhide fiber is composed of collagen fibers, which in turn are composed of tropocollagen molecules. Tropocollagen molecules are composed of three entangled polypeptide chains, each with a length of about 1,000 amino acid residues. Tropocollagen molecules are about 300nm long and 1.5nm in diameter. The surface of cowhide fiber contains a large number of amino, hydroxyl and carboxyl groups, which can achieve good moisture absorption and moisturizing effects.

[0006] The cowhide fibers in cowhide are a three-dimensional network structure formed by collagen fibers branching, cross-linking, branching, and cross-linking again. The cowhide fibers grasped by physical methods are a mixture of irregularly shaped, short and long fiber structures and hyperbranched structures. For example, in the patent with application number 201510228478.4, cowhide fibers can be used as spinning materials with a length of 5mm to 50mm. Cowhide fibers with a length of less than 5mm or non-fibrous cowhide fibers will be discharged as impurities during the spinning process.

[0007] Data shows that the moisture regain of cowhide fiber can reach 31%, that is, 100g of cowhide fiber can absorb 31g of water under normal conditions, while the surface remains dry. Therefore, cowhide fiber can be used as a very good humidity regulator.

[0008] In summary, in order to solve the technical problem of how to solve the lack of anti-static and active moisture absorption functions of polyurethane foam in the above-mentioned prior art, the present invention proposes a method for preparing polyurethane foam with humidity regulating ability. Summary of the invention

[0009] The present invention provides a method for preparing a polyurethane foam with humidity regulating ability. The method utilizes a large amount of active hydrogen components on the surface of cowhide fibers, adds the cowhide fibers into the polyurethane foam, and reacts with isocyanate components to form crosslinks; by adding the cowhide fibers into the polyurethane foam, the antistatic, moisture regulating, flame retardant and strength of the two-component polyurethane foam can be greatly improved.

[0010] To achieve the above object, the present invention is implemented by the following technical solutions:

[0011] A method for preparing polyurethane foam with humidity regulating ability comprises the following preparation steps:

[0012] S1 Pretreatment of cowhide fiber;

[0013] S2 Preparation of polyurethane foam with humidity regulation ability

[0014] The S21 polyurethane foam polyol component is mixed with the polyurethane foam isocyanate component through a feeder;

[0015] S22 coating the mixed components on a release paper or a release film or injecting into a mold;

[0016] S23 high temperature curing;

[0017] S24 peels off the release paper or film or the mold to obtain the polyurethane foam.

[0018] As a further improvement of this scheme, the components in the following preparation steps are calculated by weight:

[0019] The pretreatment of S1 leather fiber specifically includes the following steps:

[0020] The cowhide fiber and the cowhide fiber pretreatment agent are mixed and stirred at a stirring speed of 3000 to 5000 revolutions per minute, and then allowed to stand for 12 to 24 hours to obtain a paste of pretreated cowhide fibers;

[0021] in,

[0022] 1-20 parts of cowhide fiber;

[0023] 5-20 parts of cowhide fiber pretreatment agent.

[0024] As a further improvement of the present solution, the kraft fiber pretreatment agent is any one or more of polyether polyol, dioctyl phthalate, and dioctyl terephthalate.

[0025] As a further improvement of this solution, the polyurethane foam polyol component includes the following components in parts by weight:

[0026] 100 parts of polyether polyol;

[0027] Catalyst: 0.05-0.5 parts;

[0028] Water: 0-5 parts;

[0029] Cowhide fiber: 1-20 parts;

[0030] Organic silicon foam regulator: 0.5-5 parts;

[0031] Liquid flame retardant: 5-10 parts;

[0032] Powdered flame retardant: 5 to 10 parts.

[0033] As a further improvement of this solution, the polyurethane foam polyisocyanate component is any one or more of MDI, TDI, HDI trimer, and IPDI trimer.

[0034] As a further improvement of the present solution, the polyurethane foam polyisocyanate component is a mixture of HDI trimer and IPDI trimer, and the HDI trimer and IPDI trimer are mixed in a ratio of 1:1.

[0035] As a further improvement of this scheme,

[0036] The liquid flame retardant is a phosphorus-based flame retardant;

[0037] The powdered flame retardant is a phosphorus-based powdered flame retardant.

[0038] As a further improvement of this scheme,

[0039] The phosphorus-based flame retardant is triethyl phosphate;

[0040] The phosphorus-based powder flame retardant is ethyl ethylene phosphate.

[0041] As a further improvement of this solution, the polyether polyol is

[0042] Polyoxypropylene polyol, molecular weight 1000, hydroxyl value 112mg KOH / g,

[0043] Any one or two of polyoxypropylene polyol, molecular weight 2000, hydroxyl value 56 mg KOH / g.

[0044] The method for preparing a polyurethane foam with humidity regulating ability of the present invention has the following beneficial effects:

[0045] 1) The present invention adds cowhide fiber to the polyol component of the foam, which is a natural collagen fiber. The fiber surface contains a large amount of active hydrogen, such as amino, hydroxyl and carboxyl groups. These active hydrogen components can react with excess isocyanate groups to crosslink, thereby greatly improving the tear strength of the polyurethane foam; the preferred solution of the present invention pre-treats the cowhide fiber, effectively reducing the agglomeration of the cowhide fiber in the polyurethane foam, making the cowhide fiber more evenly dispersed; the presence of fibrous cowhide fiber increases the open cell ratio of the polyurethane foam, and the active hydrogen components that do not participate in the reaction inside can continue to exist, thereby giving the polyurethane foam antistatic, humidity regulation, flame retardancy and other capabilities;

[0046] 2) The addition of kraft fiber, as a protein, provides sufficient nitrogen source for the flame retardancy of polyurethane foam. Therefore, the present invention only needs to add phosphorus flame retardant or metal hydroxide to obtain synergistic flame retardant effect, thereby obtaining excellent flame retardant performance.

[0047] 3) The polyurethane foam with humidity regulating capability of the present invention can absorb moisture in the environment when the humidity in the environment increases during the use of the polyurethane foam, thereby greatly reducing the humidity in the environment. When the humidity in the environment decreases, the absorbed moisture is discharged, thereby preparing for regulating the humidity when the humidity increases next time, thereby playing the role of regulating the humidity in the environment;

[0048] 4) The above functions can be widely used in relatively closed spaces for thermal insulation and humidity regulation, such as battery compartments of new energy vehicles, energy storage power station compartments, 5G base station compartments, sports shoe insoles, high-end floor mats, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 The cross-sectional view 1 of the polyurethane foam with humidity regulating ability of the present invention is obtained in Example 4;

[0050] Figure 2 Figure 2 is a cross-sectional view of the polyurethane foam prepared in Example 4 of the polyurethane foam having humidity regulating ability of the present invention. DETAILED DESCRIPTION

[0051] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is further described below in conjunction with embodiments and drawings:

[0052] Example 1

[0053] The preparation steps of a polyurethane foam with humidity regulating ability are as follows:

[0054] Polyurethane foam material preparation configuration:

[0055] Polyurethane foam polyol component configuration:

[0056] Polyoxypropylene polyol, molecular weight 2000, hydroxyl value 56 mg KOH / g: 100 parts

[0057] Organic tin catalyst: 0.05 parts

[0058] Water: 0 parts

[0059] Cowhide fiber: 1 piece, length 0.1mm;

[0060] Polyether modified silicone oil cell regulator: 0.5 parts

[0061] Liquid flame retardant: 8 parts, specifically phosphorus flame retardant triethyl phosphate

[0062] Powdered flame retardant: 5 parts, specifically aluminum hydroxide flame retardant

[0063] Polyurethane foam polyisocyanate component: polyisocyanate is MDI

[0064] The above materials are stirred evenly to form a two-component polyurethane polyol component;

[0065] The mixture is mixed with the isocyanate component by a feeder, coated on a release paper or a release film, or injected into a mold, cured at 90°C for 5 minutes, and the release paper, film or mold is peeled off to obtain the desired polyurethane foam.

[0066] The amount of the isocyanate component added is such that the molar ratio of isocyanate groups to hydroxyl groups is 1.05, and the isocyanate groups are excessive.

[0067] Example 2

[0068] Polyurethane foam material preparation configuration:

[0069] Polyurethane foam polyol component configuration:

[0070] Polyoxypropylene polyol, molecular weight 1000, hydroxyl value 112 mg KOH / g: 100 parts

[0071] Organotin catalyst: 0.5 parts

[0072] Water: 5 parts

[0073] Cowhide fiber (pre-treated): 10 pieces of cowhide fiber length 2mm

[0074] Polyether modified silicone oil cell regulator: 5 parts

[0075] Liquid flame retardant: 5 parts phosphorus flame retardant triethyl phosphate

[0076] Powdered flame retardant: 5 parts of phosphorus-based powdered flame retardant is ethyl ethylene phosphate

[0077] Polyurethane foam polyisocyanate components:

[0078] Polyisocyanate mixed with HDI trimer and IPDI trimer in a ratio of 1:1;

[0079] The above materials are stirred evenly to form a two-component polyurethane polyol component;

[0080] Mix with isocyanate components through a feeder, apply on release paper, release film or inject into mold - cure at 90℃ for 5min - peel off release paper, film or mold - polyurethane foam

[0081] The pretreatment steps of cowhide fiber are as follows:

[0082] The cowhide fiber was mixed with 10 times the mass fraction of polyether polyol (polyoxypropylene polyol, molecular weight 1000, hydroxyl value 112 mg KOH / g), and stirred at high speed at a stirring speed of 4000 rpm, and then allowed to stand for 12 hours to obtain a paste-like pretreated cowhide fiber;

[0083] The isocyanate component is added in an amount such that the molar ratio of isocyanate groups to hydroxyl groups is 1.1, and the isocyanate groups are in excess;

[0084] Compared with Example 1, the amount of cowhide fiber added in this embodiment is increased by 10 times, and it can still be dispersed evenly; this is due to the pretreatment and pre-dispersion process of the cowhide fiber; after experiments, the amount of cowhide fiber added exceeds 10 parts, that is, the cowhide fiber needs to be pretreated;

[0085] In this embodiment, the preferred polyisocyanate of HDI trimer and IPDI trimer mixed in a ratio of 1:1 is selected to obtain yellowing-resistant polyurethane foam on the one hand, and to give the polyurethane foam high resilience on the other hand.

[0086] Example 3

[0087] Polyurethane foam material preparation configuration:

[0088] Polyurethane foam polyol component configuration:

[0089] Polyoxypropylene polyol, molecular weight 2000, hydroxyl value 56 mg KOH / g: 100 parts

[0090] Compound catalyst of cyclohexylmethyl tertiary amine and organotin: 0.2 parts

[0091] Water: 3 parts

[0092] Cowhide fiber (pre-treated): 15 parts

[0093] Polyether modified silicone oil micropore regulator: 2.5 parts

[0094] Liquid flame retardant: 7 parts

[0095] Powdered flame retardant: 8 parts

[0096] Polyurethane foam polyisocyanate components:

[0097] Polyisocyanate mixed with HDI trimer and IPDI trimer in a ratio of 1:1;

[0098] The above materials are stirred evenly to form a two-component polyurethane polyol component;

[0099] Mix with isocyanate components through a feeder, apply on release paper, release film or inject into mold - cure at 90℃ for 5min - peel off release paper, film or mold - polyurethane foam

[0100] The length of the cowhide fiber is 3 mm; after pretreatment, that is, mixing with 15 times the mass of DOTP and stirring at high speed, the stirring speed is 5000 revolutions / min, and then standing for 24 hours, a paste-like and easily dispersible pretreated cowhide fiber is obtained;

[0101] The liquid flame retardant is triethyl phosphate flame retardant; the powdered flame retardant is ethyl ethylene phosphate;

[0102] The amount of the isocyanate component added is such that the molar ratio of isocyanate groups to hydroxyl groups is 1.08, and the isocyanate groups are excessive.

[0103] Example 4

[0104] Polyurethane foam material preparation configuration:

[0105] Polyurethane foam polyol component configuration:

[0106] Polyoxypropylene polyol, molecular weight 1000, hydroxyl value 112 mg KOH / g: 100 parts

[0107] Dibutyltin dilaurate catalyst: 0.1 parts

[0108] Water: 0.8 parts

[0109] Cowhide fiber (pre-treated): 20 parts

[0110] Polyether modified silicone oil cell regulator: 4 parts

[0111] Liquid flame retardant: 9 parts

[0112] Powdered flame retardant: 5 parts

[0113] Polyurethane foam polyisocyanate components:

[0114] Polyurethane foam polyisocyanate is TDI

[0115] The above materials are stirred evenly to form a two-component polyurethane polyol component;

[0116] Mix with isocyanate components through a feeder, apply on release paper, release film or inject into mold - cure at 90℃ for 5min - peel off release paper, film or mold - polyurethane foam

[0117] The length of the cowhide fiber is 1 mm; after pretreatment, 8 times the mass of dioctyl terephthalate (DOTP) is mixed and stirred at high speed at a stirring speed of 4500 rpm, and then left to stand for 24 hours to obtain a paste-like and easily dispersible cowhide fiber;

[0118] The liquid flame retardant is propyl dimethyl phosphate; the powdered flame retardant is ethyl ethylene phosphate;

[0119] The amount of the isocyanate component added is such that the molar ratio of isocyanate groups to hydroxyl groups is 1.07, and the isocyanate groups are excessive.

[0120] like Figures 1-2 As shown, through the scanning electron microscope of the product obtained in this embodiment, it can be clearly seen that the cowhide fiber is evenly distributed in the polyurethane foam: a part of it is in direct contact with the polyurethane foam, and its internal active hydrogen reacts with the polyurethane foam, and most of it is exposed inside the pores of the polyurethane foam, increasing the open porosity of the polyurethane foam, and giving the polyurethane foam antistatic and humidity regulating capabilities through the hydrophilic groups on its surface;

[0121] Comparative Example 1

[0122] Polyurethane foam material preparation configuration:

[0123] Polyurethane foam polyol component configuration:

[0124] Polyoxypropylene polyol, molecular weight 1000, hydroxyl value 112 mg KOH / g: 100 parts

[0125] Organotin catalyst: 0.5 parts

[0126] Water: 5 parts

[0127] Polyether modified silicone oil cell regulator: 5 parts

[0128] Liquid flame retardant: 5 parts phosphorus flame retardant triethyl phosphate

[0129] Powdered flame retardant: 5 parts phosphorus-based powdered flame retardant - ethyl ethylene phosphate

[0130] Polyurethane foam polyisocyanate components:

[0131] Polyisocyanate mixed with HDI trimer and IPDI trimer in a ratio of 1:1;

[0132] The above materials are stirred evenly to form a two-component polyurethane polyol component;

[0133] Mix with isocyanate components through a feeder, apply on release paper, release film or inject into mold - cure at 90℃ for 5min - peel off release paper, film or mold - polyurethane foam

[0134] The amount of the isocyanate component added is such that the molar ratio of isocyanate group to hydroxyl group is 1.1, and the isocyanate group is in excess.

[0135] This comparative example refers to Example 2, and the difference from Example 2 is that it does not contain pretreatment

[0136] The last cowhide fiber.

[0137]

[0138] Note: The moisture absorption rate of the material is the rate of mass increase measured after placing the material in a standard environment of 25°C and 60% humidity for 24 hours.

[0139] The present invention adds cowhide fiber to the foam polyol component to obtain natural collagen fiber, the fiber surface of which contains a large amount of active hydrogen, such as amino, hydroxyl and carboxyl groups. These active hydrogen components can react with excess isocyanate groups to cross-link, thereby greatly improving the tear strength of the polyurethane foam; in addition, the active hydrogen components inside the collagen fiber can continue to exist, thereby giving the polyurethane foam anti-static, humidity regulating, flame retardant and other capabilities.

[0140] A polyurethane foam with humidity regulating ability. During the use of the polyurethane foam, if the humidity in the environment increases, the polyurethane foam can absorb moisture in the environment, thereby greatly reducing the humidity in the environment. When the humidity in the environment decreases, the absorbed moisture is discharged, thereby preparing for regulating the humidity when the humidity increases next time.

[0141] The above functions can be widely used in relatively closed spaces for heat preservation and humidity regulation, such as new energy battery warehouses, energy storage power station warehouses, 5G base station warehouses, etc.

[0142] A polyurethane foam with humidity regulating ability also has good flame retardant properties. Due to the addition of cowhide fiber, the amount of flame retardant added in the formula can be significantly reduced; this is because cowhide fiber is a protein fiber, which can provide a nitrogen source for the material and form a synergistic effect with the phosphorus flame retardant added in the present invention.

[0143] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0144] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A method for preparing a polyurethane foam having humidity regulating ability, characterized in that: The method comprises the following preparation steps: S1 Pretreatment of cowhide fiber; S2 Preparation of polyurethane foam with humidity regulation ability The S21 polyurethane foam polyol component is mixed with the polyurethane foam isocyanate component through a feeder; S22 coating the mixed components on a release paper or a release film or injecting into a mold; S23 high temperature curing; S24 peels off the release paper or film or the mold to obtain the polyurethane foam.

2. The method for preparing polyurethane foam with humidity regulating ability according to claim 1, characterized in that: The components in the following preparation steps are calculated by weight: The pretreatment of S1 leather fiber specifically includes the following steps: The cowhide fiber and the cowhide fiber pretreatment agent are mixed and stirred at a stirring speed of 3000 to 5000 revolutions per minute, and then allowed to stand for 12 to 24 hours to obtain a paste of pretreated cowhide fibers; in, 1-20 parts of cowhide fiber; 5-20 parts of cowhide fiber pretreatment agent.

3. The method for preparing polyurethane foam with humidity regulating ability according to claim 2, characterized in that: The kraft fiber pretreatment agent is any one or more of polyether polyol, dioctyl phthalate and dioctyl terephthalate.

4. The method for preparing polyurethane foam with humidity regulating ability according to claim 1, characterized in that: The polyurethane foam polyol component comprises the following components in parts by weight: 100 parts of polyether polyol; Catalyst: 0.05-0.5 parts; Water: 0-5 parts; Cowhide fiber: 1-20 parts; Organic silicon foam regulator: 0.5-5 parts; Liquid flame retardant: 5-10 parts; Powdered flame retardant: 5 to 10 parts.

5. The method for preparing polyurethane foam with humidity regulating ability according to claim 1, characterized in that: The polyurethane foam polyisocyanate component is any one or more of MDI, TDI, HDI trimer and IPDI trimer.

6. The method for preparing polyurethane foam with humidity regulating ability according to claim 1, characterized in that: The polyurethane foam polyisocyanate component is a mixture of HDI trimer and IPDI trimer, and the HDI trimer and the IPDI trimer are mixed in a mass ratio of 1:

1.

7. The method for preparing polyurethane foam with humidity regulating ability according to claim 4, characterized in that: The liquid flame retardant is a phosphorus-based flame retardant; The powdered flame retardant is a phosphorus-based powdered flame retardant.

8. The method for preparing polyurethane foam with humidity regulating ability according to claim 4, characterized in that: The phosphorus-based flame retardant is triethyl phosphate; The phosphorus-based powder flame retardant is ethyl ethylene phosphate.

9. The method for preparing polyurethane foam with humidity regulating ability according to claim 4, characterized in that: The polyether polyol is Polyoxypropylene polyol, molecular weight 1000, hydroxyl value 112mg KOH / g, Any one or two of polyoxypropylene polyol, molecular weight 2000, hydroxyl value 56 mg KOH / g.

10. An application of polyurethane foam with humidity regulating ability, characterized in that: The polyurethane foam prepared by the method for preparing a polyurethane foam with humidity regulating ability as described in any one of claims 1 to 9 is applied to new energy battery warehouses, energy storage power station warehouses, and 5G base station warehouses.

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