A polyurethane foam, its preparation method and application

Abstract

This application belongs to the technical field of polymer materials, and particularly relates to a polyurethane foam and its preparation method and application. The polyurethane foam provided in this application introduces a specific amount of polyether polyol initiated by an amine containing a terminal secondary amino group or an amine containing a terminal tertiary amino group into the polyether polyol, omitting the use of a catalyst, fundamentally solving the hidden dangers of VOC and odor. The polyurethane foam prepared with this highly active polyether polyol has excellent VOC, odor performance and resistance to damp heat aging, and has low density and fast curing characteristics. Although no catalyst is used during the preparation process, the normal production process efficiency can still be ensured, meeting the production process requirements of components such as automobiles and furniture, and improving the health and comfort of end users.

Description

Technical Field

[0001] This application belongs to the technical field of polymer materials, and particularly relates to a polyurethane foam, a preparation method thereof, and an application thereof. Background Art

[0002] Due to its excellent physical properties and processing flexibility, polyurethane foam is widely used in transportation means such as automobiles, high-speed rails, and airplanes. It is usually used for preparing interior parts such as automotive carpets, front panels, seats, and coat racks, as well as household mattresses and other fields. In recent years, manufacturers in both the automotive and household industries have put forward more stringent requirements to their foam suppliers, especially for the standards of the content of volatile organic compounds (VOC) in polyurethane foam, odor, and resistance to damp heat aging performance.

[0003] VOC has olfactory irritation and certain toxicity, mainly including aldehydes, amines, benzene compounds, and low-molecular-weight alcohols. VOC and odor mainly come from small and medium-sized molecules such as catalysts, polyethers, and silicone oils, among which catalysts and polyethers play a dominant role. Therefore, to reduce the VOC content in polyurethane materials, it is necessary to select or modify the raw materials for polyurethane foaming to effectively reduce the presence of volatile organic compounds. For example, the existing patent literature discloses a low-VOC hydrolysis-resistant polyurethane foam and a preparation method thereof, which achieve the effect of low VOC through the selection and compound use of various polyether polyols, but the introduction of amine catalysts still has potential risks of odor and VOC sources. The existing technology also discloses obtaining low-odor polyurethane foam through the use of a combination of deodorants, but this does not fundamentally reduce VOC. In addition, the resistance to damp heat aging performance of polyurethane foam in the existing technology also needs to be further improved.

[0004] In view of this, there is an urgent need to develop a polyurethane foam that can fundamentally reduce the VOC and odor of polyurethane foam and simultaneously improve the resistance to damp heat aging performance of polyurethane foam. Summary of the Invention

[0005] Therefore, the technical problem to be solved by this application is to overcome the defects in the prior art that the VOC and odor of polyurethane foam cannot be fundamentally reduced and the resistance to damp heat aging performance needs to be further improved, so as to provide a polyurethane foam, a preparation method thereof, and an application thereof.

[0006] To this end, this application provides the following technical solutions:

[0007] According to one aspect of this application, a polyurethane foam is provided, the raw materials of which include component A and component B. Component A is an isocyanate-reactive component, and component B is an isocyanate component.

[0008] Among them, component A includes the following components in parts by mass:

[0009]

[0010] Among them, the polyether polyol includes 50-100 parts of polyether polyol initiated by a first initiator (polyether polyol A1, i.e., high-activity polyether polyol), and based on the total molar amount of the first initiator, it includes 50%-100% of an amine containing a terminal tertiary amino group and / or an amine containing a terminal secondary amino group.

[0011] In some optional embodiments, the amine containing a terminal secondary amino group or the amine containing a terminal tertiary amino group has any one of the following structures:

[0012]

[0013]

[0014] Among them, R 1 、R 2 、R 3 、R 5 、R 6 、R 7 、R 8 、R 9 、R 10 、R 11 、R 12 and R 13 are independently selected from one of the alkylene groups of C 1 -C 4 ; R 4 is selected from one of the alkyl groups of C 1 -C 4 . As an example, R 1 、R 2 、R 3 、R 5 、R 6 、R 7 、R 8 、R 9 、R 10 、R 11 、R 12 and R 13 are independently selected from at least one of -CH 2 -, -CH 2 CH 2 -, -CH 2 CH 2 CH 2 -, -CH 2 CH 2 CH 2 CH 2 -; R 4 is selected from -CH 3 、-CH 2 CH3 , -CH 2 CH 2 CH 3 , -CH 2 CH 2 CH 2 CH 3 One of the following.

[0015] In the amine containing a terminal secondary amino group or the amine structure containing a terminal tertiary amino group, one end contains a tertiary amino group / secondary amino group. After the N atom in the amino group is used as an initiator to carry out ring-opening polymerization with a polymerization monomer, a polyether polyol containing a tertiary amino group is formed, and the spatial steric hindrance of the N atom in the tertiary amino group is small, maintaining the high activity of its lone pair electrons. The catalytic reaction in polyurethane can be realized by utilizing the characteristics of the amino group in its structure.

[0016] In some optional embodiments, the hydroxyl value of the polyether polyol initiated by the first initiator is 22 - 56 mgKOH / g, preferably 28 - 35 mgKOH / g; the primary hydroxyl group content is ≥65%, preferably ≥80%.

[0017] In this application, the polyether polyol initiated by the amine containing a terminal secondary amino group or the amine containing a terminal tertiary amino group can be obtained by self-preparation, and the preparation method is conventional in the art. For example, ring-opening polymerization is carried out using ethylene oxide, propylene oxide, and butylene oxide, etc. Preferably, ethylene oxide and propylene oxide are used. The reaction molar ratio of the initiator to ethylene oxide and propylene oxide is 1:m:n, where m and n are selected from integers of 0 - 200. Preferably, the ethylene oxide content in the polyether polyol is 20 - 40%. Typically and non-limitingly, its preparation method may include the following steps:

[0018] S1: Add the first initiator (amine containing a terminal secondary amino group or amine containing a terminal tertiary amino group, and may also contain a conventional initiator), catalyst into the reaction kettle, raise the temperature, introduce the epoxide, and carry out the aging reaction;

[0019] S2: Adjust the temperature, introduce the epoxide, and continue the reaction;

[0020] S3: Transfer the material to the refining kettle, add acid and water for neutralization, dehydrate and filter to obtain the target polyether polyol.

[0021] In some optional embodiments, the catalyst in S1 is a common catalyst in the art such as an alkali metal catalyst and / or an organic base, a phosphazene catalyst, etc. Preferably, it is one or more of sodium hydroxide, potassium hydroxide, potassium tert-butoxide, sodium metal, and phosphazene catalyst; the epoxide in S1 is one or at least two of ethylene oxide, propylene oxide, and butylene oxide, preferably propylene oxide and ethylene oxide;

[0022] And / or, the temperature rise in S1 is 85 - 120 °C, and the pressure is below 0.5 MPaG;

[0023] And / or, propylene oxide is introduced into S1, and the dosing period of propylene oxide is 5 - 10 h;

[0024] And / or, the aging reaction time in S1 is 0.5 - 2 h.

[0025] In some alternative embodiments, the temperature of S2 is adjusted to 110 - 130 °C, and the pressure is less than 0.5 MPaG;

[0026] And / or, ethylene oxide is added to S2, and the dosing period of ethylene oxide is 1 - 3 h;

[0027] And / or, the continuous reaction time of S2 is 0.5 - 2 h.

[0028] In some alternative embodiments, the acid in S3 is one or more of phosphoric acid, sulfuric acid, acetic acid, hydrochloric acid, preferably phosphoric acid and / or hydrochloric acid;

[0029] Preferably, the pH is adjusted to 4 - 7 in the neutralization step in S3;

[0030] And / or, the dehydration reduces the moisture to <500 ppm.

[0031] In some alternative embodiments, the first initiator further includes 0 - 50% of a conventional initiator; by way of example, the content of the conventional initiator in the first initiator is 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, or within the range composed of any of the above values;

[0032] And / or, the polyether polyol further includes 0 - 50 parts of polyether polyol initiated by a conventional initiator; by way of example, the amount of polyether polyol initiated by a conventional initiator included in the polyether polyol can be 5 parts, 10 parts, 15 parts, 20 parts, 25 parts, 30 parts, 35 parts, 40 parts, 45 parts, 50 parts, or within the range composed of any of the above values.

[0033] In some alternative embodiments, the conventional initiator includes at least one of, but is not limited to, alkanolamines, polyamines, polyols. It can be understood that when the conventional initiator includes multiple initiators, it can be a mixture of the same type of initiators (such as a mixture of different alkanolamines, a mixture of different polyamines, a mixture of different polyols, etc.), or a mixture of different types of initiators (such as a mixture of alkanolamine and polyamine, a mixture of polyamine and polyol, etc.).

[0034] In some alternative embodiments, the alkanolamine includes at least one of, but is not limited to, diethanolamine (DEA), triethanolamine (TEA), diisopropanolamine (DIPA), and methyldiethanolamine (MDEA), etc.;

[0035] And / or, the polyamine includes at least one of aliphatic or aromatic amines containing more than two N atoms and having an active hydrogen content of ≥2 per molecule. For example, the polyamine includes, but is not limited to, at least one of ethylenediamine, propylenediamine, diethylenetriamine, m-phenylenediamine, m-xylylenediamine, diaminotoluene, 4,4'-methylenebis(2-chloroaniline), etc.

[0036] And / or, the polyol includes, but is not limited to, at least one of ethylene glycol, glycerol, trimethylolpropane, pentaerythritol or sucrose.

[0037] In some alternative embodiments, the NCO content in the component B is 18% - 35%, preferably 22 - 32%.

[0038] In some alternative embodiments, the mass ratio of component A to component B is 100:30 - 70, preferably 100:45 - 65.

[0039] The initiator in the polyether polyol (polyether polyol A2) initiated by the conventional initiator can be an alkanolamine, polyamine or polyol with a functionality of 3 and / or 4 and / or 5; the average functionality of the polyether polyol A2 is 3 - 5, the hydroxyl value is 24 - 42 mgKOH / g, the ethylene oxide content is 20 - 40%, and based on the weight of the polyether polyol A2, the primary hydroxyl group content is greater than or equal to 80%, calculated based on the amount of primary and secondary hydroxyl groups.

[0040] In some alternative embodiments, the mass parts of the surfactant are 0.2 - 1.5, preferably 0.3 - 1.0; the surfactant can be obtained by preparation or through commercial channels. The method of preparation can be carried out according to the methods commonly used by those skilled in the art; examples of surfactants obtained through commercial channels include, but are not limited to, M-8818LO, M-8805, M-7734LF2, M7771LF2 of Jiangsu MSD Chemical Co., Ltd., B8870, B8002, B8715, B8734LF2 of Evonik Industries AG, HR-8870, HR8871 of Dow Chemical Company, etc. The surfactant can be used alone or in combination.

[0041] In some alternative embodiments, the mass parts of the blowing agent are 3 - 6, preferably 3.5 - 4.5; the blowing agents that can be used include chemical blowing agents and / or physical blowing agents, examples of which include, but are not limited to, water, CO 2 , alkane blowing agents, chlorine- or fluorine-containing blowing agents, etc. Examples of the alkane blowing agents are butane, n-pentane, cyclopentane, isopentane, etc., and examples of the chlorine- or fluorine-containing blowing agents are 1,2-dichlorofluoroethane, pentafluoropropane, pentafluorobutane, dichloromethane, etc.

[0042] As a preferred technical solution of the present application, the blowing agent is selected from one or more of water, CO 2 , 1,2-dichlorofluoroethane, butane, n-pentane, cyclopentane and isopentane, preferably water.

[0043] In some alternative embodiments, the mass parts of the crosslinking agent are 0.2 to 1.5, preferably 0.3 to 0.8; the crosslinking agents that can be used include ethanolamine, diethanolamine, triethanolamine, ethylenediamine, ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, hexanediol, cyclohexanediol, diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol, glycerol, trimethylolpropane or pentaerythritol, etc. At least one of them, preferably one or two of diethanolamine and triethanolamine.

[0044] In some alternative embodiments, the component B can be selected from any known isocyanate, modified isocyanate, and isocyanate prepolymer.

[0045] As a preferred technical solution of the present application, the isocyanate component of the component B includes polyphenylmethane polyisocyanate, 2,4-diphenylmethane diisocyanate, 4,4-diphenylmethane diisocyanate and polyol-modified isocyanate prepolymer, preferably a mixture of polyphenylmethane polyisocyanate, 4,4-diphenylmethane diisocyanate and polyol-modified isocyanate prepolymer, and the NCO content is 18 to 35%, preferably 22 to 32%.

[0046] The polyphenylmethane polyisocyanate described in the present application refers to a mixture of polyphenylmethane polyisocyanate with a functionality of 3 or more.

[0047] According to another aspect of the present application, a method for preparing the above-mentioned polyurethane foam is provided, including the following steps:

[0048] Mix component A and component B, and foam to obtain the polyurethane foam.

[0049] In some alternative embodiments, the temperature of the mixing is 20 to 40 °C, preferably fully mixed at 22 to 35 °C;

[0050] And / or, the temperature of the foaming is 50 to 80 °C, and the foaming time is 60 to 100 s.

[0051] Specifically, the method for preparing the polyurethane foam includes: mixing component A and component B at 20 to 40 °C, preferably 22 to 35 °C, fully mixing and stirring, and then quickly injecting into a mold with a mold temperature of 50 to 80 °C for foaming. After 60 to 120 s, open the mold to obtain the polyurethane foam.

[0052] In the preparation steps described in this application, for the specific preparation parameters, processes, and other conditions that are not elaborated in detail, the preparation parameters and processes commonly used by those skilled in the art can be adopted.

[0053] The molded density of the polyurethane foam prepared according to the technical solution of this application is 50 - 80 kg / m 3 , which is suitable for foaming and molding in a mold at 50 - 80 °C and has high production efficiency.

[0054] According to another aspect of this application, there is provided an application of the above-mentioned polyurethane foam or the polyurethane foam prepared by the above-mentioned preparation method in the field of transportation tools or household items. For example, it can be applied to the preparation of high-resilience polyurethane soft foams such as automotive parts and household mattresses.

[0055] The polyurethane foam described in this application has a wide range of uses. As long as the physical properties such as the density and wet heat compression set of the polyurethane foam in this application meet the requirements of any application field, it can be applied to the corresponding field.

[0056] As a preferred use, the polyurethane foam described in this application can be applied to the production of automotive and household parts, and is preferably applied to the production of interior products such as automotive carpets and front panels.

[0057] The technical solution of this application has the following advantages:

[0058] The polyurethane foam provided by this application can eliminate the use of catalysts by introducing a specific amount of polyether polyol initiated by an amine containing a terminal secondary amino group or an amine containing a terminal tertiary amino group into the polyether polyol, fundamentally solving the hidden dangers of VOC and odor. The polyurethane foam prepared with this highly active polyether polyol has excellent VOC, odor performance, and wet heat aging resistance, and has low density and fast curing characteristics. Although no catalyst is used during the preparation process, it can still ensure the normal production process efficiency, meet the production process requirements of automotive, household and other parts, and improve the health and comfort of end users.

[0059] In the polyether polyol initiated by the first initiator of the polyurethane foam provided by this application, the use of a mixed initiator, while ensuring that the obtained polyether polyol has high activity, takes into account the control of the synthesis process, obtains a polyether polyol with a narrow molecular weight distribution, and the mixed initiator can effectively adjust and control the functionality, so as to have better adaptability in the application field of polyurethane foam, and further reduce the VOC content and odor level. Detailed Embodiments

[0060] The following examples are provided for a better understanding of the present application, but are not limited to the best implementation mode described, and do not limit the content and protection scope of the present application. Any product identical or similar to the present application obtained by anyone under the inspiration of the present application or by combining the features of the present application with other prior arts shall fall within the protection scope of the present application.

[0061] If no specific experimental steps or conditions are specified in the examples, the conventional experimental steps or conditions described in the literature in the field can be used. If no manufacturer is specified for the reagents or instruments used, they are all conventional reagent products that can be obtained commercially.

[0062] The main raw materials used in the examples and comparative examples of the present application are as follows. Other raw materials are common commercially available unless otherwise specified:

[0063] Polyether polyol A1-1, using the compound shown in the following structure 1 as an initiator, propylene oxide and ethylene oxide as polymerization monomers and ethylene oxide end-capping, ethylene oxide content of 20%, primary hydroxyl content of 85%, hydroxyl value of 28 mgKOH / g;

[0064] Structure 1, 3-Dimethylaminopropylamine was purchased from Aladdin; the specific synthesis includes the following steps:

[0065] 1) Add 102.18g (1 mol) of 3-dimethylaminopropylamine and potassium hydroxide equivalent to 0.2% of the total mass of 3-dimethylaminopropylamine, propylene oxide, and ethylene oxide into a self-priming reactor. Seal the reactor and replace it with nitrogen three times. When the reactor is heated to 65°C, evacuate the reactor for 1 hour. Heat the reactor to 110°C and control the pressure below 0.5MPa. Add 3370g of propylene oxide. Add the materials after 5 hours. Continue the reaction until the pressure no longer decreases.

[0066] 2) Control the pressure below 0.4 MPa and add 750 g of ethylene oxide. Add the mixture over 2 h and continue the reaction until the pressure no longer decreases;

[0067] 3) Cool to 75-80℃ to remove the monomer for 1 hour, add appropriate amount of hydrochloric acid to the product to neutralize the pH to about 7, remove water and unreacted hydrochloric acid, and discharge the product. Determine the hydroxyl value and trialdehyde content of the product.

[0068] Polyether polyol A1-2, starting from the compound shown in structure 1 and diethylenetriamine, propylene oxide and ethylene oxide are polymerization monomers and ethylene oxide is terminated, the ethylene oxide content is 30%, the primary hydroxyl content is 89%, and the hydroxyl value is 34 mgKOH / g;

[0069] Diethylenetriamine was purchased from Aladdin; the specific synthesis includes the following steps:

[0070] 1) Add 61.3g (0.6mol) 3-dimethylaminopropylamine, 41.27g (0.4mol) diethylenetriamine and 0.05% of the total mass of 3-dimethylaminopropylamine, diethylenetriamine, propylene oxide and ethylene oxide to a self-priming reactor, with a phosphazene:potassium hydroxide mass ratio of 1:1. Close the reactor and replace it with nitrogen three times. Vacuum the reactor until it is heated to 70°C for 1h. Heat the reactor to 110°C and control the pressure below 0.4MPa. Add 3650g propylene oxide. Add the materials after 5h, and continue the reaction until the pressure no longer decreases.

[0071] 2) Control the pressure below 0.3 MPa and add 1560 g of ethylene oxide. Add the mixture over 2 h and continue the reaction until the pressure stops decreasing.

[0072] 3) Cool to 75-80℃ to remove the monomer for 1 hour, add appropriate amount of hydrochloric acid to the product to neutralize the pH to about 7, remove water and unreacted hydrochloric acid, and discharge the product. Determine the hydroxyl value and trialdehyde content of the product.

[0073] Polyether polyol A1-3, using the compound shown in structure 2 as an initiator, propylene oxide and ethylene oxide as polymerization monomers and ethylene oxide end-capping, ethylene oxide content of 20%, primary hydroxyl content of 87%, hydroxyl value of 35 mgKOH / g;

[0074] Structure 2, N,N-dimethyldipropylenetriamine was purchased from Aladdin; the specific synthesis includes the following steps:

[0075] 1) Add 159.3g (1mol) of N,N-dimethyldipropylenetriamine and 0.05% of the total mass of N,N-dimethyldipropylenetriamine, propylene oxide and ethylene oxide to a self-priming reactor, with a phosphazene composite catalyst composition of 2:1 mass ratio of phosphazene to potassium hydroxide. Close the reactor and replace it with nitrogen three times. Vacuum the reactor until it is heated to 90°C for 1h. Heat the reactor to 120°C and control the pressure below 0.4MPa. Add 3850g of propylene oxide. Add the materials after 5h, and continue the reaction until the pressure no longer decreases.

[0076] 2) Control the pressure below 0.3 MPa and add 960 g of ethylene oxide. The addition should be completed within 2 hours and the reaction should continue until the pressure no longer decreases.

[0077] 3) Cool to 75-80℃ to remove the monomer for 1 hour, add appropriate amount of hydrochloric acid to the product to neutralize the pH to about 7, remove water and unreacted hydrochloric acid, and discharge the product. Determine the hydroxyl value and trialdehyde content of the product.

[0078] Polyether polyol A1-4, using the compound shown in Structure 3 and triethylenediamine as a mixed initiator, propylene oxide and ethylene oxide as polymerization monomers and ethylene oxide-capped, with an ethylene oxide content of 18%, a primary hydroxyl content of 84%, and a hydroxyl value of 36 mg KOH / g;

[0079] Structure 3 is N-Methylethylenediamine, purchased from Aladdin; the specific synthesis steps are as follows:

[0080] 1) Add 59.3 g (0.8 mol) of N-methylethylenediamine, 20.6 g (0.2 mol) of diethylenetriamine, and a phosphazene composite catalyst equivalent to 0.05% of the total mass of N-methylethylenediamine, diethylenetriamine, propylene oxide, and ethylene oxide in a self-priming reactor. The composition is a phosphazene: potassium hydroxide mass ratio of 2:1. Seal the reactor, displace with nitrogen three times, and evacuate for 1 h when the reactor temperature rises to 90 °C. Raise the reactor temperature to 120 °C and add 4230 g of propylene oxide while controlling the pressure below 0.4 MPa. The feeding is completed in 5 h, and continue the reaction until the pressure no longer decreases.

[0081] 2) Add 880 g of ethylene oxide while controlling the pressure below 0.3 MPa. The addition is completed in 2 h, and continue the reaction until the pressure no longer decreases.

[0082] 3) Cool to 75 - 80 °C to remove monomers for 1 h. Add an appropriate amount of hydrochloric acid to the product to neutralize the pH to about 7, remove water and unreacted hydrochloric acid, and discharge the product. Measure the hydroxyl value, trialdehyde content, etc. of the product.

[0083] Polyether polyol A2-1, starting with glycerol, propylene oxide and ethylene oxide as polymerization monomers and ethylene oxide-capped, with an ethylene oxide content of 23%, a primary hydroxyl content of 85%, and a hydroxyl value of 28 mg KOH / g.

[0084] Polyether polyol A2-2, starting with trimethylolpropane, propylene oxide and ethylene oxide as polymerization monomers and ethylene oxide-capped, with an ethylene oxide content of 25%, a primary hydroxyl content of 88%, and a hydroxyl value of 35 mg KOH / g.

[0085] Polyether polyol A2-3, starting with triethanolamine, propylene oxide and ethylene oxide as polymerization monomers and ethylene oxide-capped, with an ethylene oxide content of 23%, a primary hydroxyl content of 87%, and a hydroxyl value of 33 mg KOH / g;

[0086] Polyether polyol A2-4, starting with triethylenediamine, propylene oxide and ethylene oxide as polymerization monomers and ethylene oxide-capped, with an ethylene oxide content of 21%, a primary hydroxyl content of 86%, and a hydroxyl value of 36 mg KOH / g.

[0087] Surfactant, Evonik B8734LF2.

[0088] Crosslinking agent 1: Triethanolamine;

[0089] Crosslinking agent 2: Diethanolamine.

[0090] Isocyanate B1, a mixture of polyphenylmethane polyisocyanate, 4,4-diphenylmethane diisocyanate and polyol-modified isocyanate prepolymer, with an NCO content of 30%;

[0091] Isocyanate B2, a mixture of polyphenylmethane polyisocyanate, 4,4-diphenylmethane diisocyanate and polyol-modified isocyanate prepolymer, with an NCO content of 22%;

[0092] Isocyanate B3, a mixture of polyphenylmethane polyisocyanate, 4,4-diphenylmethane diisocyanate and polyol-modified isocyanate prepolymer, with an NCO content of 32%.

[0093] Catalyst 1: Huntsman, dimethylaminopropylamine;

[0094] Catalyst 2: Huntsman, N,N-dimethyl-N,N-bis(2-hydroxypropyl)-1,3-propanediamine (CAS No. 63469-23-8).

[0095] Example 1

[0096] This example provides a polyurethane foam, and its preparation method includes the following steps:

[0097] According to the proportions in Table 1: Weigh the raw materials of Component A and mix them evenly at 25°C, then mix them fully with the weighed Component B at 25°C and inject them into a mold with a mold temperature of 65°C for reaction foaming. After 120 s, open the mold and take out the foam (the gel time needs to be less than 70 s) to obtain the polyurethane foam.

[0098] Performance testing:

[0099] The standard for testing density is ISO845;

[0100] Evaluation standards for odor and VOC: BMW cubic chamber test method, GS97014-3:2022 (VOC) GS97014-4:2021 (Odour);

[0101] Wet heat aging test: Place the foam in a constant temperature and humidity aging chamber at 60°C and 90% RH for 240 h, and refer to the standard: GB / T10802-2023 to test the compression set;

[0102] Rise time: Visual method. After mixing Component A and Component B under the set material temperature and ambient temperature conditions, the time when the liquid material turns milky white and starts to foam;

[0103] Gel time: Visual method. After components A and B are mixed under the set material temperature and ambient temperature conditions, the foam begins to form a strength that can resist slight external pressure and has a relatively stable three-dimensional structure. The gel time is also called the drawing time. The common test method: The time required for the first thin filament to appear from the mixing of the foaming material to inserting a bamboo stick or the like 1 cm deep into the foam.

[0104] The raw materials of each component in Table 1 are calculated by mass parts.

[0105] Examples 2 - 9

[0106] This example provides a polyurethane foam, and its preparation method is the same as that of Example 1. The specific composition of the raw materials is shown in Table 1.

[0107] Comparative Examples 1 - 4

[0108] This comparative example provides a polyurethane foam, and its preparation method is the same as that of Example 1. The specific composition of the raw materials is shown in Table 2.

[0109] In the following Table 1 and Table 2, " / " represents that the corresponding component is not added or the relevant performance test is not carried out.

[0110] Composition and test results of examples in Table 1

[0111]

[0112]

[0113] Composition and test results of comparative examples in Table 2

[0114]

[0115]

[0116] From the data in the above table, it can be seen that by using polyether polyols initiated by amines containing terminal secondary amino groups or amines containing terminal tertiary amino groups, the fast rise and curing of the foam can be maintained without a catalyst, fundamentally solving the hidden dangers of VOC and odor. The prepared polyurethane foam has excellent VOC and odor performance, and has superior moisture and heat resistance and low density. From the comparison between Example 1 and Example 2, it can be seen that in high-activity polyether polyols, the use of a mixed initiator can further reduce the VOC content and odor level. Among them, the gel time of Comparative Example 1 and Comparative Examples 3 - 4 is above 70 s, which does not meet the foaming requirements, and subsequent performance tests are not carried out.

[0117] Obviously, the above embodiments are merely examples for clear illustration and not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or variations can be made based on the above description. It is not necessary and impossible to exhaustively list all implementation manners here. And the obvious changes or variations derived therefrom are still within the protection scope of the present invention.

Claims

1. A polyurethane soft foam, characterized in that: The raw materials include component A and component B, wherein component A is an isocyanate reactive component, and component B is an isocyanate component. Wherein, the component A comprises the following components in parts by weight: 100 parts of polyether polyol, Surfactant 0.2~1.5 parts; 3~6 parts of foaming agent; 0.2~1.5 parts of cross-linking agent; The polyether polyol comprises 50 to 100 parts of a polyether polyol initiated by a first initiator, and comprises 50% to 100% of an amine containing a terminal tertiary amine group and / or an amine containing a terminal secondary amine group, based on the total molar amount of the first initiator; The polyether polyol initiated by the first initiator has a hydroxyl value of 22-56 mgKOH / g and a primary hydroxyl content of ≥65%; The amine containing a terminal secondary amine group or the amine containing a terminal tertiary amine group has any of the following structures: （Ⅰ） ； （Ⅱ）； （Ⅲ）； （Ⅳ）； （Ⅴ）； （Ⅵ）； （Ⅶ）； Among them, R1, R2, R3, R5, R6, R7, R8, R9, R 10 , R 11 , R 12 and R 13 R4 is independently selected from one of C1-C4 alkylene groups; The first initiator also includes 5% to 50% of a conventional initiator; the conventional initiator includes at least one of an alcohol amine, a polyamine, and a polyol, and the polyamine includes at least one of ethylenediamine, propylenediamine, diethylenetriamine, metaphenylenediamine, metaphenylenediamine, diaminotoluene, and 4,4'-methylenebis(2-chloroaniline).

2. The polyurethane soft foam according to claim 1, characterized in that: The alcohol amine includes at least one of diethanolamine, triethanolamine, diisopropanolamine, and methyldiethanolamine; The polyol includes at least one of ethylene glycol, glycerol, trimethylolpropane, pentaerythritol or sucrose.

3. The polyurethane soft foam according to any one of claims 1 to 2, characterized in that: The NCO content in the component B is 18% to 35%.

4. The polyurethane soft foam according to claim 3, characterized in that: The mass ratio of component A to component B is 100:30-70.

5. A method for preparing a polyurethane soft foam according to any one of claims 1 to 4, characterized in that: The steps include: Component A and component B are mixed and foamed to obtain the polyurethane foam.

6. The method for preparing polyurethane soft foam according to claim 5, characterized in that: The mixing temperature is 20-40°C; And / or, the foaming temperature is 50-80° C., and the foaming time is 60-100 s.

7. Use of the polyurethane soft foam according to any one of claims 1 to 4 or the polyurethane soft foam prepared by the preparation method according to claim 5 or 6 in the field of transportation or home furnishing.

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