阅读说明：本技术 一种高回弹聚氨酯泡沫及其制备方法 (High-resilience polyurethane foam and preparation method thereof ) 是由 于正洋 何国龙 沈国平 于 2019-08-21 设计创作，主要内容包括：本发明提供了一种高回弹聚氨酯泡沫,针对现有技术中产品物性不足的缺陷,原料中加入胺类扩链剂,并与其他组分配合使用,可大幅提高泡沫的撕裂性能及断裂伸长率等物理性能,同时具有较好的气味和TVOC表现。本发明还提供了所述泡沫的制备方法。(The invention provides a high-resilience polyurethane foam, aiming at the defect of insufficient physical properties of products in the prior art, the amine chain extender is added into the raw materials and is matched with other components for use, so that the physical properties of the foam, such as tearing property, elongation at break and the like, can be greatly improved, and the foam has better smell and TVOC performance. The invention also provides a preparation method of the foam.)

1. The high-resilience polyurethane foam is characterized by being obtained by reacting organic isocyanate and an isocyanate reactive component, wherein the isocyanate reactive component comprises polyether polyol, a catalyst, a foaming agent and an amine chain extender, and the amine chain extender is an amine compound without hydroxyl.

2. The foam of claim 1, wherein the organic isocyanate is one or more of toluene diisocyanate, diphenylmethane diisocyanate, and polymethylene polyphenyl isocyanates.

3. The foam according to claim 1 or 2, wherein the polyether polyol has a functionality of 2 to 4, preferably 3, and a hydroxyl number of 22.5 to 36.5mgKOH/g, preferably 27.5 to 35.5 mgKOH/g; more preferably, the polyether polyol is prepared by polymerizing propylene oxide and ethylene oxide, and the content of propylene oxide is 70-90%, preferably 75-85%.

4. A foam according to any of claims 1 to 3, wherein the amine chain extender has a functionality of 2 and an amine number of from 190 to 370 mgKOH/g.

5. The foam of any one of claims 1 to 4, wherein the amine chain extender is 4,4' -bis (sec-butylamino) -diphenylmethane and/or a self-made amine chain extender, and the self-made amine chain extender is prepared from the following raw materials: a compound containing two primary amine groups, an ester compound containing one unsaturated double bond, an optional ester compound containing two unsaturated double bonds, and an optional basic catalyst; the preparation method comprises the following steps:

step one, adding the compound containing two primary amino groups into a reactor, starting stirring, and adding an optional basic catalyst;

and step two, controlling the temperature of the reactor to be 30-135 ℃, preferably 40-70 ℃ for reaction, adding the ester compound containing one unsaturated double bond into the reactor for reaction, adding an optional ester compound containing two unsaturated double bonds for reaction after the reaction is completed, and discharging after the reaction is finished.

6. The foam according to any one of claims 1 to 5, wherein the compound containing two primary amine groups is one or more of 1, 3-cyclohexyldimethylamine, 1, 3-cyclohexanediamine, hexamethylenediamine, diethylenetriamine and polyetheramine; the ester compound containing one unsaturated double bond is selected from diethyl maleate and/or diethyl fumarate; the ester compound containing two unsaturated double bonds is selected from one or more of diethylene glycol diacrylate, dipropylene glycol diacrylate, tripropylene glycol diacrylate and 1, 6-hexanediol diacrylate.

7. The foam according to any one of claims 1 to 6, wherein the total mass of the compound having two primary amino groups, the ester compound having one unsaturated double bond, and the ester compound having two unsaturated double bonds is taken as a calculation reference:

the dosage of the compound containing two primary amino groups is 20-60%, preferably 23.4-55.7%;

the dosage of the ester compound containing one unsaturated double bond is 40-80%, preferably 42.3-74.6%;

the dosage of the ester compound containing two unsaturated double bonds is 0-20%, preferably 2-10%.

8. A foam according to any of claims 1 to 7, wherein the molar ratio of isocyanate groups in the organic isocyanate to active hydrogen atoms in the isocyanate-reactive component is from 1: 1 to 1.5, preferably 1: 1.1 to 1.2.

9. A process for preparing the foam of any one of claims 1 to 8, wherein the organic isocyanate and isocyanate-reactive component are mixed uniformly and injected into a mould for reaction to obtain a polyurethane foam after the reaction is finished.

Technical Field

The invention relates to a high resilience polyurethane foam, in particular to a polyurethane foam for seats and a preparation method of the foam.

Background

The high-resilience cold curing polyurethane foam has the advantages of high resilience, low cost and the like, is particularly suitable for seat materials, is continuously improved along with the living standard of people, has higher and higher requirements on the physical properties of the foam, particularly has the properties of tearing property, breaking elongation and the like, and not only influences the product yield during production, but also has certain influence on the service life of the seat. The prior seat composite material system is mainly divided into two types of TM/MT systems and a modified MDI system. The TM/MT system composite material has the characteristics of good rebound resilience, low preparation density and the like, but the main component TDI has toxicity and strong volatility, and the problems of TDI use and transportation and hazardous chemical package recovery bring more burden to production enterprises under the condition of increasingly emphasizing green production and severe environmental protection situation. Compared with a TM/MT system, the modified MDI system has the characteristics of environmental protection, belongs to common chemicals, has small volatility and is more convenient to transport and use, but the tear tensile strength of polyurethane foam prepared by the modified MDI system is poor, and the service life of the automobile seat is influenced to a certain extent.

Therefore, in order to solve the problems of the prior art, it is required to provide a high resilience polyurethane foam having excellent properties and a method for preparing the same.

Disclosure of Invention

Aiming at solving the problems in the prior art, the invention provides a high-resilience polyurethane foam, aiming at the defect of insufficient physical properties of products in the prior art, the amine chain extender is added into the raw materials and is matched with other components for use, so that the physical properties of the foam, such as tearing property, elongation at break and the like, can be greatly improved, and meanwhile, the foam has better smell and TVOC performance. The invention also provides a preparation method of the foam.

The high-resilience polyurethane foam is obtained by reacting organic isocyanate with an isocyanate reactive component, wherein the isocyanate reactive component comprises polyether polyol, a catalyst, a foaming agent and an amine chain extender, and the amine chain extender is an amine compound without hydroxyl.

The organic isocyanate may be isocyanate compounds commonly used in the art, and examples thereof include, but are not limited to, Toluene Diisocyanate (TDI), diphenylmethane diisocyanate (MDI), isophorone diisocyanate (IPDI), Hexamethylene Diisocyanate (HDI), dicyclohexylmethane diisocyanate (HMDI), Naphthalene Diisocyanate (NDI), p-phenylene diisocyanate (PPDI), 1, 4-cyclohexane diisocyanate (CHDI), Xylylene Diisocyanate (XDI), cyclohexanedimethylene diisocyanate (HXDI), trimethyl-1, 6-hexamethylene diisocyanate (TMHDI), tetramethylm-xylylene diisocyanate (TMXDI), norbornane diisocyanate (NBDI), dimethylbiphenyl diisocyanate (TODI), methylcyclohexyl diisocyanate (HTDI), and the like, and polyisocyanates obtained by reacting the above isocyanate monomers, polyisocyanate monomers, and the like, Isocyanate prepolymer, isocyanate dimer, isocyanate trimer and the like, and such isocyanate compounds may be used alone or in combination. Preferably, the organic isocyanate is one or more of toluene diisocyanate, diphenylmethane diisocyanate and polymethylene polyphenyl isocyanate.

The polyether polyol refers to a class of compounds polymerized from a small molecule alcohol or a small molecule amine as an initiator and an alkylene oxide as a polymerization monomer, examples of the initiator include, but are not limited to, glycerin, trimethylolpropane, ethylenediamine, pentaerythritol, xylitol, dimethylethyltriamine, sorbitol, sucrose, etc., and examples of the alkylene oxide include, but are not limited to, ethylene oxide, propylene oxide, butylene oxide, etc. Preferably, the polyether polyol has a functionality of 2 to 4, preferably 3, and a hydroxyl value of 22.5 to 36.5mgKOH/g, preferably 27.5 to 35.5 mgKOH/g.

More preferably, the polyether polyol is prepared by polymerizing propylene oxide and ethylene oxide, and the content of propylene oxide is 70-90%, preferably 75-85%.

The isocyanate-reactive component may also optionally include polyester polyols, polycarbonate polyols, polymer polyols, biobased polyols, and the like. In a preferred example, the isocyanate-reactive component does not comprise any or all of a polyester polyol, a polycarbonate polyol, a polymer polyol, a bio-based polyol. The adoption of polyester polyol, polycarbonate polyol, polymer polyol and bio-based polyol can increase the production cost, the operation complexity, reduce the production efficiency, reduce the product stability and the like, and in addition, the increase of the raw materials is difficult to achieve the advantages of good foam resilience, small compression deformation, good hand feeling and the like caused by the use of single polyether polyol.

The catalyst may be selected from catalysts commonly used in the art, examples of which include, but are not limited to, triethylenediamine, bis (dimethylaminoethyl) ether, dimethylethanolamine, dimethylaminoethoxyethanol, and commercial examples of which include, but are not limited to, KC120, KC100, KC102L, KC162, KC164, KC168, and the like, which may be used alone or in combination.

The foaming agent may be selected from foaming agents commonly used in the art, and examples thereof include, but are not limited to, physical foaming agents, chemical foaming agents, and the like, and preferably, the foaming agent is water.

The amine chain extender means a polyfunctional amine compound having an active hydrogen atom and no hydroxyl group, which is capable of reacting with an isocyanate group, such as an aliphatic amine compound, an aromatic amine compound, and the like, and more specific examples include, but are not limited to, ethylenediamine, 1, 3-propanediamine, 4' -bis (sec-butylamino) -diphenylmethane, dihydroxyethylaniline, and the like.

In a preferred embodiment, the amine chain extender does not contain low molecular weight amine compounds such as phenylenediamine and ethylenediamine. The reaction of low molecular weight amine compounds such as phenylenediamine and ethylenediamine with isocyanate groups is very violent, the gelling speed is too fast, and the reaction process is not easy to control, so that the amine compounds are not adopted in the preferred embodiment of the invention.

Preferably, the amine chain extender has a functionality of 2 and an amine value of 190-370 mgKOH/g.

Further preferably, the amine chain extender is 4,4' -bis (sec-butylamino) -diphenylmethane and/or a self-made amine chain extender, wherein the self-made amine chain extender is prepared from the following raw materials: a compound containing two primary amine groups, an ester compound containing one unsaturated double bond, an optional ester compound containing two unsaturated double bonds, and an optional basic catalyst; the preparation method comprises the following steps:

step one, adding the compound containing two primary amino groups into a reactor, starting stirring, and adding an optional basic catalyst;

and step two, controlling the temperature of the reactor to be 30-135 ℃, preferably 40-70 ℃ for reaction, adding the ester compound containing one unsaturated double bond into the reactor for reaction, adding an optional ester compound containing two unsaturated double bonds for reaction after the reaction is completed, and discharging after the reaction is finished.

In the second step, the "adding an optional ester compound containing two unsaturated double bonds for reaction after the reaction is completed" means that the ester compound containing two unsaturated double bonds may or may not be added during the reaction; when an ester compound containing two unsaturated double bonds is added, corresponding reaction is carried out; when the ester compound containing two unsaturated double bonds is not added, the corresponding reaction is not carried out. In addition, the method of adding the reactant into the reactor is well known in the art, and for example, a method of slowly adding dropwise, or a method of adding in portions, or a method of adding in one portion, etc. may be used without affecting the practice of the present invention, and the method of preparing the reactant by slowly adding dropwise or adding in portions is preferred.

In the preparation method of the self-made amine chain extender, inert gas can be selectively introduced or not introduced in the reaction process, and the implementation of the method is not influenced. Whether the inert gas is introduced affects the appearance of the reaction product, the appearance of the reaction product introduced with the inert gas is colorless and transparent, and the appearance of the reaction product not introduced with the inert gas is light yellow. The preparation process of the present invention preferably employs inert gas injection.

The compound containing two primary amine groups has a structure shown in a formula 1, wherein the structure shown in the formula 1 is NH₂-X₁-NH₂Wherein, X is₁Selected from aliphatic linking groups having a linear structure, aliphatic linking groups having a cyclic structure, aliphatic linking groups having a hetero atom, and aromatic linking groups.

In a preferred embodiment, X is₁The aliphatic connecting group is selected from aliphatic connecting groups with a straight chain structure, wherein the number of carbon atoms of the straight chain structure is 2-24, and preferably 4-16. In addition, X is₁When an aliphatic linking group having a linear structure is represented, the linear structure may optionally include a branch, and the number of carbon atoms of the linear structure refers to only carbon atoms of the linear structure, excluding the optional branch carbon atoms.

In a preferred embodiment, X is₁Selected from aliphatic linking groups having a cyclic structure, wherein the cyclic structure is a carbocyclic structure well known in the art, e.g., the number of carbon atoms5 to 12 ring structures, double ring structures, multiple ring structures, etc.

In a preferred embodiment, X is₁Selected from aliphatic linking groups having hetero atoms, wherein X is₁Having a linear and/or cyclic structure, optionally comprising branches; the heteroatoms are those well known in the art, such as O, S, N, P and the like; preferably, said X₁Has a linear structure; further preferably, the heteroatom is O and/or N; further preferably, X is₁Is a structure of formula 2 or a structure of formula 3;

wherein, the structure of formula 2 is

n is an integer, and 1. ltoreq. n.ltoreq.8, preferably 2. ltoreq. n.ltoreq.7; r₁Represents a hydrogen atom or a saturated aliphatic group, preferably a hydrogen atom or a methyl group; r₂Represents a saturated aliphatic linking group having 2 to 8 carbon atoms, preferably 3 to 6 carbon atoms, more preferably-CH (CH)₃)CH₂-、-CH(CH₃)CH₂CH(CH₃)CH₂-、-CH(CH₃)CH₂CH₂CH(CH₃) -one of the above;

formula 3 has the structure

p is an integer, and 1. ltoreq. p.ltoreq.4, preferably 1. ltoreq. p.ltoreq.2; r₃Represents a saturated aliphatic group or a hydrogen atom, preferably a hydrogen atom; r₄、R₅The same or different saturated aliphatic linking groups each independently represent a saturated aliphatic linking group, and preferably a saturated aliphatic linking group having a linear structure and 2 to 4 carbon atoms.

In a preferred embodiment, X is₁Selected from aromatic linking groups, refers to a group having a benzene ring structure in the group, such structures are well known in the art, and examples thereof include, but are not limited to

And the like.

In a preferred example, the compound having two primary amine groups is ethylenediamine, propylenediamine, tetramethylenediamine, 1, 5-diaminopentane, neopentyldiamine, hexamethylenediamine, octanediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, hexaethyleneheptamine, dipropylenetriamine, amine, 1, 2-cyclohexyldimethylamine, 1, 3-cyclohexyldimethylamine, 1, 4-cyclohexyldimethylamine, 1, 2-cyclohexanediamine, 1, 3-cyclohexanediamine, 1, 4-cyclohexanediamine, 4-diaminodicyclohexylmethane, p-phenylenediamine, o-phenylenediamine, m-phenylenediamine, diethyltoluenediamine, methylenebis (4-amino-3-methylbenzoate), 4-methylenebis (2, 6-diethyl) aniline, one or more of 4, 4-methylene bis (2, 6-diisopropylaniline) and polyether amine, preferably one or more of 1, 3-cyclohexyldimethylamine, 1, 3-cyclohexanediamine, hexamethylenediamine, diethylenetriamine and polyether amine.

The polyether amine refers to a polymer with a main chain of a polyether structure and an amine group as a terminal active functional group, and the polyether amine can be obtained by commercial purchase, such as JEFFAMINE series products produced by Hensman company, and the like, and can also be prepared by a conventional method without affecting the implementation of the invention. Preferably, the polyetheramine has a weight average molecular weight of not more than 500; more preferably, the polyether amine has a weight average molecular weight of 200 to 450.

The compound containing two primary amine groups as a raw material has the following beneficial effects: the two primary amine groups react with unsaturated groups to form secondary amine groups, the formed secondary amine groups are used as reaction groups to react with organic isocyanate, a good chain extension effect is provided, and simultaneously, urea bonds formed by the reaction of the secondary amine groups and the organic isocyanate can endow the foam with good physical properties.

The ester compound containing one unsaturated double bond has a structure shown in a formula 9, wherein the structure shown in the formula 9 isWherein, R is₆、R₇The same or different, each independently represent an organic group inert to isocyanate groups, preferably a saturated aliphatic group, more preferably an ethyl group. Examples of the ester compound having one unsaturated double bond include, but are not limited to, cis-butenedioic acid diester compounds, trans-butenedioic acid diester compounds, and the like, which may be used alone or in combination.

The above-mentioned maleic diester-based compound refers to a compound having a cis-butene structure and two ester-based structures in the molecule, and examples thereof include, but are not limited to, dimethyl maleate, diethyl maleate, dibutyl maleate, diisobutyl maleate, dioctyl maleate, diisooctyl maleate and the like, and such maleic diester-based compounds may be used alone or in combination.

The trans-butenedioic acid diester-based compound refers to a compound having a trans-butene structure and two ester-based structures in the molecule, and examples thereof include, but are not limited to, dimethyl fumarate, diethyl fumarate, dibutyl fumarate, diisobutyl fumarate, dioctyl fumarate, diisooctyl fumarate, and the like, and such trans-butenedioic acid diester-based compounds may be used alone or in combination.

Further preferably, the ester compound containing one unsaturated double bond is selected from diethyl maleate and/or diethyl fumarate.

The ester compound containing one unsaturated double bond as a raw material has the following beneficial effects: the unsaturated double bond reacts with primary amine with higher reactivity to form secondary amine with proper reactivity, so that a more proper chain extension effect is provided for a system; steric hindrance effect provided by the ester bond in the structure further reduces the reactivity of secondary amine, and meanwhile, the ester bond is beneficial to improving the performance of the prepared product.

The ester compound containing two unsaturated double bonds has a structure shown as a formula 10, wherein the structure shown as the formula 10 isWherein, X is₂Selected from aliphatic linking groups or linking groups having ether linkages.

In a preferred embodiment, X is₂The group is selected from aliphatic linking groups having a linear structure or a cyclic structure, and optionally including a branched chain, examples of which include, but are not limited to, a linear structure having 1 to 8 carbon atoms, a cyclic structure having 5 to 12 carbon atoms, a bicyclic structure, a polycyclic structure, and the like.

In a preferred embodiment, X is₂Selected from the group consisting of a linking group having an ether bond, the linking group having an ether bond having a structure of formula 11,

wherein q is an integer, and 1. ltoreq. q.ltoreq.8, preferably 1. ltoreq. q.ltoreq.4; r₈、R₉、R₁₀Identical or different, each independently represent a hydrogen atom or a saturated aliphatic group, preferably R₈、R₉、R₁₀Each independently represents a hydrogen atom or a methyl group.

The repeating units in the structures of formula 2, formula 3 and formula 11 only indicate that each repeating unit independently corresponds to the structure shown by the repeating unit in the corresponding structure; for example, the structure of formula 2 includes,

the structure, also comprising,

the structure, also comprising,

structure; and further formula 3The structure not only comprises the components of the structure,

the structure, also comprising,

the structure, also comprising,

structure; again, the structure of formula 11 includes,

the structure, also comprising,

the structure, also comprising,

and (5) structure.

In a preferred example, the ester compound having two unsaturated double bonds is selected from ethylene glycol diacrylate, diethylene glycol diacrylate, dipropylene glycol diacrylate, tripropylene glycol diacrylate, 1, 4-butanediol diacrylate, 1, 6-hexanediol diacrylate, polyethylene glycol diacrylate, neopentyl glycol diacrylate, tetraethylene glycol diacrylate and the like, and such compounds may be used alone or in combination. Preferably, the ester compound containing two unsaturated double bonds is selected from one or more of diethylene glycol diacrylate, dipropylene glycol diacrylate, tripropylene glycol diacrylate and 1, 6-hexanediol diacrylate.

The ester compound containing two unsaturated double bonds as a raw material has the following beneficial effects: two unsaturated double bonds react with primary amine groups to form more secondary amines in a molecular chain, so that the reaction functionality of the synthesized amine chain extender is improved, and the secondary amines react with organic isocyanate to form more urea bonds, so that the tensile strength and the tear strength of the product can be improved, and the density of the product can be reduced.

The basic catalyst may be selected from basic catalysts commonly used in the art, and examples thereof include, but are not limited to, basic organic compounds, basic inorganic compounds, and the like, and more specific examples include, but are not limited to, sodium ethoxide, potassium tert-butoxide, potassium ethoxide, sodium tert-butoxide, methyl potassium, methyl sodium, butyl lithium, butyl potassium, triethyl aluminum, and the like, and such catalysts may be used alone or in combination.

In a preferred embodiment of the present invention, the basic catalyst is necessary. The reaction efficiency can be effectively improved and the reaction time can be shortened by adding the alkaline catalyst.

In a preferred embodiment of the present invention, the preparation raw material does not contain a basic catalyst. The reaction is more stable without adding alkaline catalyst, and the reaction is easy to control.

In a preferred embodiment, based on the total mass of the compound having two primary amine groups, the ester compound having one unsaturated double bond, and the ester compound having two unsaturated double bonds:

the dosage of the compound containing two primary amino groups is 20-60%, preferably 23.4-55.7%;

the dosage of the ester compound containing one unsaturated double bond is 40-80%, preferably 42.3-74.6%;

the dosage of the ester compound containing two unsaturated double bonds is 0-20%, preferably 2-10%.

In a preferred embodiment, the ester compound containing two unsaturated double bonds is necessary, and the two unsaturated double bonds react with primary amine groups to enable the synthesized amine chain extender to have higher functionality, so that the tensile strength and tear strength of the product can be improved, and the density of the product can be reduced.

In a preferred embodiment, the basic catalyst is used in an amount of 0 to 1%, preferably 0.001 to 0.1%, more preferably 0.01 to 0.05%, based on the total mass of the compound having two primary amino groups, the ester compound having one unsaturated double bond, and the ester compound having two unsaturated double bonds.

When the self-made amine chain extender is used for polyurethane foam, the physical properties of the foam can be improved, such as tensile strength, tearing strength and the like.

The isocyanate-reactive component also contains a surfactant, which can be selected from surfactants commonly used in the art, examples of which include, but are not limited to, polysiloxane-alkylene oxide block or graft copolymers and the like, and commercial examples include, but are not limited to, SC870, SC815 and the like produced by warfarin chemistry.

In a preferred embodiment, based on the total mass of the isocyanate-reactive components:

the using amount of the polyether polyol is 90-98%, and preferably 92-96%;

the dosage of the catalyst is 0.1-1%, preferably 0.2-0.8%;

the amount of the foaming agent is 1-5%, preferably 2-4%;

the using amount of the amine chain extender is 0.1-5%, and preferably 0.2-3%;

the dosage of the surfactant is 0.1-5%, preferably 0.2-3%.

The molar ratio of isocyanate groups in the organic isocyanate to active hydrogen atoms in the isocyanate-reactive component is 1: 1 to 1.5, preferably 1: 1.1 to 1.2.

The preparation method of the foam comprises the steps of uniformly mixing the organic isocyanate and the isocyanate reactive component, injecting the mixture into a mold for reaction, and obtaining the polyurethane foam after the reaction is finished.

It should be noted that the specific operations, such as the selection of the reactor, the selection of the stirring device, the control of the mold temperature, the reaction time, etc., which are not described in the preparation method, can be implemented by referring to the disclosure of the prior art, such as polyurethane foam (third edition) published by the chemical industry publisher (written by zhui, liu yi army, etc.), etc., without affecting the implementation of the present invention.

The invention has the beneficial effects that: when the self-made amine chain extender is used for polyurethane foam, the physical properties of the foam, such as tensile strength, tearing strength and the like, can be improved greatly, and meanwhile, the self-made amine chain extender has good smell and TVOC performance.

Detailed Description

The examples and comparative examples used the following starting materials:

organic isocyanate: WANNATE8223B, NCO content 32.6%, Vanhua Chemicals;

polyether polyol 1: functionality of 3, hydroxyl value of 27.5mgKOH/g, ethylene oxide and propylene oxide polymerized, propylene oxide content of 80%;

polyether polyol 2: the functionality is 3, the hydroxyl value is 34.5mgKOH/g, the epoxy ethane and the epoxy propane are polymerized, and the content of the epoxy propane is 85 percent;

polymer polyol: the functionality is 3, the hydroxyl value is 32mgKOH/g, the viscosity is not less than 25 ℃ and not more than 6500 mpa.s, acrylonitrile and styrene are grafted, and the solid content is 40 percent. (ii) a

Catalyst: KC120, KC100, KC102L, wanhua chemistry;

foaming agent: water;

amine chain extenders: self-made amine chain extender 1 with an amine value of 235.894 mgKOH/g; self-made amine chain extender 2 with an amine value of 196.350 mgKOH/g; ethylenediamine with an amine value of 1870 mgKOH/g; 4,4' -bis (sec-butylamino) -diphenylmethane, having an amine value of 361.935 mgKOH/g;

surfactant (b): SC815, wanhua chemistry;

polyether amine: d400, Hensmei corporation.

The self-made amine chain extender is prepared as follows.

Amine chain extender 1

Under the atmosphere of nitrogen, 298.4g of 1, 3-cyclohexyldimethylamine are added into the flask, and stirring is started; 661.1g of diethyl maleate is slowly dropped into the flask, 39.5g of 1, 6-hexanediol diacrylate is added after stirring and reacting for 2 hours, the mixture in the flask is heated to 55 ℃ after dropping and reacting, the temperature is reduced and discharging is carried out after the reaction time is 70 hours, and the amine chain extender 1 is obtained.

Amine chain extender 2

Under the nitrogen atmosphere, 700g of polyetheramine D400 is added into a flask, and stirring is started; and slowly dropwise adding 280g of diethyl maleate into the flask, stirring for reacting for 2 hours, then adding 20g of tripropylene glycol diacrylate, heating the mixture in the flask to 55 ℃ for reacting after the dropwise adding is finished, and cooling and discharging after the reaction time is 70 hours to obtain the amine chain extender 2.

The amounts of the raw materials used in the examples and comparative examples are shown in Table 1.

TABLE 1

Examples and comparative examples polyurethane foams were prepared as follows: according to table 1, the organic isocyanate was stirred uniformly for use, and the isocyanate-reactive components were pre-mixed uniformly for use; the organic isocyanate and the isocyanate reactive component are quickly mixed and stirred for 6 seconds, and then poured into a mold with the temperature of 55 ℃ for reaction, and polyurethane foam is obtained after the reaction is finished.

Examples 1 to 5 are preferable examples of the present invention, and examples 6 to 8 are not preferable examples of the present invention.

The foams obtained in the examples and comparative examples were tested and the test properties are shown in Table 3.

TABLE 3