Foamable polyurethane composition, modified polyurethane and preparation method thereof, polyurethane foam material and preparation method thereof

Abstract

The invention relates to the technical field of foaming polyurethane, and discloses a foamable polyurethane composition, a modified polyurethane and a preparation method thereof, a polyurethane foam material and a preparation method thereof, wherein the composition comprises polyurethane, polar monomer grafted polypropylene and an amino compound, and based on the total weight of the composition, the content of the polyurethane is 70-95wt%, the content of the polar monomer grafted polypropylene is 3-29.9wt%, and the content of the amino compound is 0.1-3wt%. The invention modifies the polyurethane by adopting the polar monomer grafted polypropylene and the amino compound, and the polyurethane cooperates with the polar monomer grafted polypropylene and the amino compound, so that the prepared modified polypropylene has better viscoelastic properties, thereby making the prepared polyurethane foam material have better foaming effect.

Description

Technical Field

[0001] The invention relates to the technical field of foamed polyurethane, and in particular to a foamable polyurethane composition, a modified polyurethane and a preparation method thereof, a polyurethane foam material and a preparation method thereof. Background Art

[0002] Thermoplastic polyurethane (TPU) foam materials have the advantages of low density, good resilience, wear resistance, yellowing resistance, and good low-temperature flexibility. They can be used in shoe materials, cushioning gaskets, packaging and transportation, automobiles and other fields, and therefore have attracted widespread attention.

[0003] Among them, polyurethane is polymerized by long-chain segments and short-chain segments. Generally, the soft segment is composed of long-chain diols, and the hard segment is composed of polyisocyanates and chain extenders. The types of soft segments and hard segments affect the hardness and strength of polyurethane. Hydrogen bonds are mostly present in the hard segment, which plays a physical cross-linking role, making polyurethane have higher strength and better wear resistance. The more hydrogen bonds there are, the stronger the intermolecular force is, and the higher the strength of polyurethane is. Compared with the force of intermolecular chemical bonds, hydrogen bonds are a physical force. At higher temperatures, the chain segments receive energy and move, and hydrogen bonds disappear. Therefore, during the growth of bubbles, increasing the foaming temperature will cause the hydrogen bonds to disappear, reduce the strength of polyurethane, and cause bubbles to rupture, merge, collapse, etc.; when the foaming temperature is low, the foamed polyurethane is harder, because the foaming temperature is not high enough, the bubbles lack the power to expand, and the strength of polyurethane is large, the resistance to bubble expansion is large, and the internal bubbles are not fully expanded. Therefore, the polyurethane foaming temperature range is narrow and the foaming ratio is low.

[0004] At present, polyurethane foam materials can be obtained by optimizing and modifying the polyurethane matrix, for example, optimizing TPU with a high hard segment content, increasing the hard segment content, adding graphene nucleating agents and replacing soft segments, filling hollow glass beads (HGB), adding cross-linking agents (DCP), etc. However, there are still problems such as a narrow polyurethane foaming temperature range and a low foaming ratio.

[0005] Therefore, it is of great significance to provide a new polyurethane foam material. Summary of the invention

[0006] The purpose of the present invention is to solve the problems of low foaming ratio and narrow foaming temperature range of existing polyurethanes, and to provide a foamable polyurethane composition, a modified polyurethane and a preparation method thereof, a polyurethane foam material and a preparation method thereof, wherein the polyurethane foam material has a better foaming effect.

[0007] In order to achieve the above-mentioned object, the first aspect of the present invention provides a foamable polyurethane composition, which comprises polyurethane, polar monomer grafted polypropylene and an amino compound. Based on the total weight of the composition, the content of the polyurethane is 70-95wt%, the content of the polar monomer grafted polypropylene is 3-29.9wt%, and the content of the amino compound is 0.1-3wt%.

[0008] The second aspect of the present invention provides a method for preparing a modified polyurethane, which comprises: mixing, tableting and drying the foamable polyurethane composition described in the first aspect of the present invention to obtain the modified polyurethane.

[0009] The third aspect of the present invention provides a modified polyurethane prepared by the method described in the second aspect of the present invention, wherein at 190° C., the tan δ value of the modified polyurethane in the low frequency region is reduced by more than 30% compared with the tan δ value of the polyurethane matrix in the low frequency region; and / or

[0010] At 190° C., the complex viscosity of the modified polyurethane in the low frequency region is increased by more than 40% compared with the complex viscosity of the polyurethane matrix in the low frequency region; and / or

[0011] At 190° C., the storage modulus of the modified polyurethane in the low frequency region is increased by more than 30% compared with the storage modulus of the polyurethane matrix in the low frequency region; and / or

[0012] At 190° C., the loss modulus of the modified polyurethane in the low frequency region is increased by more than 40% compared with the loss modulus of the polyurethane matrix in the low frequency region; wherein,

[0013] The polyurethane matrix is ​​obtained by tableting and drying polyurethane.

[0014] The fourth aspect of the present invention provides a method for preparing a polyurethane foam material, the method comprising: foaming the modified polyurethane described in the third aspect of the present invention in the presence of a foaming agent, and then cooling the temperature to 110-150° C. to obtain a polyurethane foam material.

[0015] The fifth aspect of the present invention provides a polyurethane foam material prepared by the method described in the fourth aspect of the present invention, wherein the polyurethane foam material has a foaming ratio of more than 9 times, an average diameter of the pores of 50-80 μm, and a pore density of (5-9.5)×10 7 Pieces / cm 3 .

[0016] Through the above technical scheme, the present invention uses polar monomer grafted polypropylene and amino compounds to modify polyurethane, and the polyurethane, polar monomer grafted polypropylene and amino compounds cooperate with each other, so that the prepared modified polypropylene has better viscoelastic properties, so that the prepared polyurethane foam material has a higher foaming ratio, a larger pore density, and a smaller pore diameter, and thus has a better foaming effect; and the method provided by the present invention can foam within a temperature range of 110-150°C, further broadening the foaming temperature range of polyurethane. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a graph showing the variation of tan δ values ​​of the modified polyurethanes prepared in Examples 1-4 of the present invention and the polyurethane matrix prepared in Comparative Example 1 at 190° C. with angular frequency.

[0018] Figure 2 This is a graph showing the variation of complex viscosity of the modified polyurethanes prepared in Examples 1-4 of the present invention and the polyurethane matrix prepared in Comparative Example 1 at 190° C. with angular frequency.

[0019] Figure 3 This is a graph showing the variation of the storage modulus of the modified polyurethanes prepared in Examples 1-4 of the present invention and the polyurethane matrix prepared in Comparative Example 1 at 190° C. with angular frequency.

[0020] Figure 4 This is a graph showing the change in loss modulus of the modified polyurethanes prepared in Examples 1-4 of the present invention and the polyurethane matrix prepared in Comparative Example 1 at 190° C. as a function of angular frequency. DETAILED DESCRIPTION

[0021] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0022] As mentioned above, the first aspect of the present invention provides a foamable polyurethane composition, which comprises polyurethane, polar monomer grafted polypropylene and amino-containing compound, and based on the total weight of the composition, the content of the polyurethane is 70-95wt%, the content of the polar monomer grafted polypropylene is 3-29.9wt%, and the content of the amino-containing compound is 0.1-3wt%. The modified polyurethane prepared from the foamable polyurethane composition that meets the above-defined conditions has better viscoelastic properties, thereby facilitating the acquisition of a polyurethane foam material with better foaming effect.

[0023] According to a preferred embodiment of the present invention, based on the total weight of the composition, the content of the polyurethane is 80-95wt%, the content of the polar monomer grafted polypropylene is 4-19wt%, and the content of the amino compound is 1-3wt%. In this preferred embodiment, the viscoelastic properties of the modified polyurethane can be further improved, thereby improving the foaming performance of the polyurethane foam material.

[0024] The polyurethane of the present invention is not particularly limited and can be obtained commercially, for example, the polyurethane produced by Huntsman Corporation is Irogian A85P4394 (Shore hardness is 85A, density is 1.12 g / cm 3 ) of polyurethane.

[0025] In some embodiments of the present invention, preferably, the amino-containing compound is an organic compound containing an amino group, an ether bond and an aromatic group, wherein the C2-C 12 Alkanes or alkanes, C6-C 18 At least one of the aromatic hydrocarbons, wherein n is an integer of 2-5.

[0026] The present invention has a wide selection range for the organic matter containing amino groups, ether bonds and aromatic groups. Preferably, the organic matter containing amino groups, ether bonds and aromatic groups is selected from at least one of phenoxyaniline, 3,3',4,4'-tetraaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 3,4-diaminodiphenyl ether, 2,4-bis(2-methylphenoxy)-aniline, 4-(2-methylphenoxy)aniline and 2-methyl-2'-aminodiphenyl ether, and more preferably at least one of phenoxyaniline, 3,3',4,4'-tetraaminodiphenyl ether and 2-methyl-2'-aminodiphenyl ether. In this preferred case, the foaming effect of the polyurethane foam material can be further improved.

[0027] In the present invention, the n amino-substituted C2-C 12 The alkane or alkane-ene includes two amino-substituted C2-C 12 Alkanes or alkanes, C2-C 12 Alkanes or alkanes, C2-C 12 An alkane or alkanediol and five amino-substituted C2-C 12 of alkanes or alkanes.

[0028] The present invention is directed to the C2-C 12 The selection range of alkanes or alkanes is relatively wide. Preferably, the n amino-substituted C2-C 12The alkane or alkaneene is selected from at least one of 1,12-diaminododecane, 1,9-diaminononane, 1,6-hexanediamine, 1,10-decanediamine, diethylenetriamine, tetraethylenepentamine and pentamethyldiethylenetriamine, and more preferably at least one of 1,12-diaminododecane, 1,9-diaminononane, diethylenetriamine and 1,6-hexanediamine, which is more conducive to modifying the polyurethane and obtaining a polyurethane foam material with better foaming effect.

[0029] In the present invention, the n amino-substituted C6-C 18 The aromatic hydrocarbons include two amino-substituted C6-C 18 Aromatic hydrocarbons, C6-C 18 Aromatic hydrocarbons, four amino-substituted C6-C 18 Aromatic hydrocarbons and five amino-substituted C6-C 18 of aromatic hydrocarbons.

[0030] The present invention is directed to the C6-C 18 The selection range of aromatic hydrocarbons is relatively wide. Preferably, the n amino-substituted C6-C 18 The aromatic hydrocarbon is selected from at least one of p-phenylenediamine, m-phenylenediamine, o-phenylenediamine, 2,4-diaminododecylbenzene, diethyltoluenediamine, 1,3,5-triaminobenzene and 1,2,4,5-tetraaminobenzene, and more preferably p-phenylenediamine and / or 2,4-diaminododecylbenzene. In this preferred case, the foaming performance of the polyurethane foam material can be further improved.

[0031] In some embodiments of the present invention, preferably, the grafting degree of the polar monomer grafted polypropylene is 1-4wt%, more preferably 1.5-3wt%. In this preferred case, the obtained polyurethane foam material can have a better foaming effect. The present invention has no particular limitation on the weight average molecular weight of the polar monomer grafted polypropylene, preferably a polar monomer grafted polypropylene with a weight average molecular weight of 2000-800000 g / mol.

[0032] The present invention has a wide selection range for the polar monomer in the polar monomer grafted polypropylene. Preferably, the polar monomer in the polar monomer grafted polypropylene is selected from at least one of acrylic acid, methacrylic acid, methyl acrylate, methyl methacrylate, maleic anhydride, epoxy acrylate, triallyl isocyanurate, hydroxyethyl methacrylate, glycidyl methacrylate and isooctyl acrylate, and more preferably at least one of triallyl isocyanurate, methyl acrylate, methacrylic acid and methyl methacrylate, which is more conducive to obtaining a polyurethane foam material with a high foaming ratio.

[0033] The second aspect of the present invention provides a method for preparing a modified polyurethane, which comprises: kneading, tableting and drying the aforementioned foamable polyurethane composition of the present invention to obtain the modified polyurethane.

[0034] In some embodiments of the present invention, preferably, the mixing conditions include: temperature of 150-200° C., preferably 180-200° C.; time of 2-20 min, preferably 2-10 min.

[0035] The present invention has no particular limitation on the equipment used for the mixing, which can be any conventional choice in the art, for example, including but not limited to using an internal mixer for mixing, and the rotation speed of the internal mixer is preferably 40-80 r / min.

[0036] The present invention has no particular limitation on the tableting, as long as the mixed material can be pressed into a sheet with a thickness of 0.5-5 mm.

[0037] The present invention has no particular limitation on the drying. Preferably, the drying conditions include: a temperature of 60-100° C. and a time of 10-60 min. The present invention has no particular limitation on the equipment used for the drying, which can be a conventional choice in the art, such as including but not limited to using an oven for drying.

[0038] In the method provided by the present invention, the polyurethane, polar monomer grafted polypropylene and amino-containing compound involved in the foamable polyurethane composition are as described above and will not be described in detail here.

[0039] The third aspect of the present invention provides a modified polyurethane prepared by the aforementioned method of the present invention, wherein at 190°C, the tanδ value of the modified polyurethane in the low frequency region is reduced by more than 30% compared with the tanδ value of the polyurethane matrix in the low frequency region; and / or

[0040] At 190° C., the complex viscosity of the modified polyurethane in the low frequency region is increased by more than 40% compared with the complex viscosity of the polyurethane matrix in the low frequency region; and / or

[0041] At 190° C., the storage modulus of the modified polyurethane in the low frequency region is increased by more than 30% compared with the storage modulus of the polyurethane matrix in the low frequency region; and / or

[0042] At 190° C., the loss modulus of the modified polyurethane in the low frequency region is increased by more than 40% compared with the loss modulus of the polyurethane matrix in the low frequency region; wherein,

[0043] The polyurethane matrix is ​​obtained by tableting and drying polyurethane. The low frequency region of the present invention is a region with an angular frequency less than 1 rad / s.

[0044] According to a preferred embodiment of the present invention, at 190° C., the tan δ value of the modified polyurethane in the low frequency region is reduced by more than 40% compared with the tan δ value of the polyurethane matrix in the low frequency region; and / or

[0045] At 190° C., the complex viscosity of the modified polyurethane in the low frequency region is increased by more than 50% compared with the complex viscosity of the polyurethane matrix in the low frequency region; and / or

[0046] At 190° C., the storage modulus of the modified polyurethane in the low frequency region is increased by more than 40% compared with the storage modulus of the polyurethane matrix in the low frequency region; and / or

[0047] At 190° C., the loss modulus of the modified polyurethane in the low frequency region is increased by more than 50% compared with the loss modulus of the polyurethane matrix in the low frequency region. The modified polyurethane meeting the above defined conditions has better viscoelastic properties, which is conducive to obtaining a polyurethane foam material with better foaming performance.

[0048] The fourth aspect of the present invention provides a method for preparing a polyurethane foam material, the method comprising: in the presence of a foaming agent, foaming and molding the modified polyurethane of the present invention, and then cooling to 110-150°C to obtain a polyurethane foam material. The foaming temperature range provided by the present invention is 110-150°C, which broadens the foaming temperature range of polyurethane compared with the existing foaming temperature range (125-140°C).

[0049] In some embodiments of the present invention, preferably, the foaming molding conditions include: temperature of 180-210°C, preferably 180-200°C; pressure of 5-15MPa, preferably 8-15MPa; time of 30-120min, preferably 30-60min. The foaming molding of the present invention is carried out in a high-pressure reactor.

[0050] The present invention has a wide selection range for the foaming agent. Preferably, the foaming agent is selected from one of N2, CO2 and butane.

[0051] In some embodiments of the present invention, preferably, after cooling the foamed product to 110-150° C., the method further comprises opening a pneumatic valve of the autoclave to release pressure for foaming, and then obtaining a polyurethane foam material.

[0052] In order to clearly describe the method of the polyurethane foam material of the present invention, a preferred specific embodiment is provided below for illustration:

[0053] (1) mixing polyurethane, polar monomer grafted polypropylene and amino compound in proportion and adding them into an internal mixer, mixing them for 2-10 min at a temperature of 180-200° C. and a rotation speed of 40-80 r / min, and then pressing the obtained product into a sheet with a thickness of 0.5-5 mm, and drying at 60-100° C. for 10-60 min to obtain a modified polyurethane;

[0054] (2) placing the modified polyurethane into a high-pressure reactor, introducing a foaming agent, saturating for 30-60 min at a temperature of 180-200° C. and a pressure of 8-15 MPa, then cooling to 110-150° C. and releasing the pressure to obtain a polyurethane foam material.

[0055] The fifth aspect of the present invention provides a polyurethane foam material prepared by the above method of the present invention, wherein the foaming ratio of the polyurethane foam material is more than 9 times, the average diameter of the pores is 50-80 μm, and the pore density is (5-9.5)×10 7 Pieces / cm 3 .

[0056] According to a preferred embodiment of the present invention, the foaming ratio of the polyurethane foam material is 11-15 times, the average diameter of the pores is 50-70 μm, and the pore density is (6-9.5)×10 7 Pieces / cm 3 The polyurethane foam material that meets the above-mentioned limiting conditions has a better foaming effect.

[0057] Unless otherwise specified, the pressures described in the present invention refer to gauge pressures.

[0058] The present invention will be described in detail below by way of examples. In the following examples, unless otherwise specified, all the raw materials used can be obtained from commercial channels.

[0059] Polyurethane: Brand: IrogianA85P4394, Shore hardness: 85A, density: 1.12g / cm 3 , Huntsman Corporation;

[0060] Triallyl isocyanurate grafted polypropylene-I: grafting degree is 2wt%, weight average molecular weight is 10000g / mol;

[0061] Triallyl isocyanurate grafted polypropylene-II: grafting degree is 1wt%, weight average molecular weight is 20000g / mol;

[0062] Methyl acrylate grafted polypropylene: grafting degree is 2wt%, weight average molecular weight is 8000g / mol;

[0063] Methacrylic acid grafted polypropylene: grafting degree is 1.5wt%, weight average molecular weight is 12000g / mol;

[0064] Methyl methacrylate grafted polypropylene: grafting degree is 2wt%, weight average molecular weight is 10000g / mol;

[0065] Isooctyl acrylate grafted polypropylene: grafting degree is 3wt%, weight average molecular weight is 6000g / mol;

[0066] The tan δ value, complex viscosity, storage modulus and loss modulus of the modified polyurethane are tested by a rotational rheometer;

[0067] The foaming ratio of the polyurethane foam material is calculated as the ratio of the density of the unfoamed sample to the density of the foamed sample, wherein the density of the unfoamed sample and the density of the foamed sample are tested with reference to GB1033-86;

[0068] The average cell diameter of the polyurethane foam material is measured by immersing the foamed sample in liquid nitrogen for cooling for 1 hour, taking it out and rapidly breaking it, and then spraying gold on the fracture surface and using a scanning electron microscope;

[0069] The polyurethane foam material was photographed using a scanning electron microscope (model Nova NanoSEM 450, FEI Company, Czech Republic), and the cell density of the polyurethane foam material was calculated using the following formula:

[0070]

[0071] Where, D-cell density, cells / cm 3 ; n-number of cells, pcs; M-magnification, times; S-photograph statistical area, cm 2 ; ρ0-density of polyurethane before foaming, g / cm 3 ;ρ-density of polyurethane after foaming, g / cm 3 , where ρ0 and ρ are obtained by referring to GB1033-86 test.

[0072] Example 1

[0073] (1) 85 g of polyurethane, 14 g of triallyl isocyanurate grafted polypropylene-I and 1 g of phenoxyaniline were mixed uniformly and added into an internal mixer, and kneaded for 5 min at a temperature of 200° C. and a rotation speed of 40 r / min. The obtained product was then pressed into a sheet with a thickness of 2 mm, and dried at 90° C. for 30 min to obtain a modified polyurethane;

[0074] (2) The modified polyurethane is placed in a high-pressure reactor, CO2 is introduced, and saturation is carried out for 60 minutes at a temperature of 200°C and a pressure of 10 MPa. The temperature is then reduced to 140°C and the pressure is released to obtain a polyurethane foam material.

[0075] Example 2

[0076] (1) 90 g of polyurethane, 8 g of methyl acrylate grafted polypropylene and 2 g of 1,12-diaminododecane were mixed uniformly and added into an internal mixer, and kneaded for 2 min at a temperature of 190° C. and a rotation speed of 50 r / min, and then the obtained product was pressed into a sheet with a thickness of 2 mm, and dried at 60° C. for 20 min to obtain a modified polyurethane;

[0077] (2) The modified polyurethane was placed in a high-pressure reactor, N2 was introduced, and saturation was performed at a temperature of 190°C and a pressure of 8 MPa for 30 minutes. The temperature was then reduced to 145°C and the pressure was released to obtain a polyurethane foam material.

[0078] Example 3

[0079] (1) 88 g of polyurethane, 10.5 g of methacrylic acid grafted polypropylene and 1.5 g of 3,3',4,4'-tetraaminodiphenyl ether were mixed uniformly and added into an internal mixer, and kneaded for 4 min at a temperature of 190° C. and a rotation speed of 80 r / min, and then the obtained product was pressed into a sheet with a thickness of 2 mm, and dried at 100° C. for 10 min to obtain a modified polyurethane;

[0080] (2) The modified polyurethane was placed in a high-pressure reactor, N2 was introduced, and saturation was performed at a temperature of 180°C and a pressure of 15 MPa for 60 minutes. The temperature was then reduced to 130°C and the pressure was released to obtain a polyurethane foam material.

[0081] Example 4

[0082] (1) 80 g of polyurethane, 18 g of methyl methacrylate grafted polypropylene and 2 g of p-phenylenediamine were mixed uniformly and added into an internal mixer, and kneaded for 10 min at a temperature of 180° C. and a rotation speed of 70 r / min, and then the obtained product was pressed into a sheet with a thickness of 2 mm, and dried at 80° C. for 60 min to obtain a modified polyurethane;

[0083] (2) The modified polyurethane is placed in a high-pressure reactor, butane is introduced, and saturation is carried out at a temperature of 200° C. and a pressure of 10 MPa for 40 minutes. The temperature is then reduced to 125° C. and the pressure is released to obtain a polyurethane foam material.

[0084] Example 5

[0085] The method of Example 1 is followed, except that in step (1), the amount of polyurethane is changed to 70 g, the amount of triallyl isocyanurate grafted polypropylene-I is changed to 29.9 g, and the amount of phenoxyaniline is changed to 0.1 g;

[0086] The other steps are the same as those in Example 1, thereby obtaining modified polyurethane and polyurethane foam material.

[0087] Example 6

[0088] The method of Example 1 is followed, except that in step (1), the same amount of triallyl isocyanurate grafted polypropylene-II is used instead of triallyl isocyanurate grafted polypropylene-I;

[0089] The other steps are the same as those in Example 1, thereby obtaining modified polyurethane and polyurethane foam material.

[0090] Example 7

[0091] The method of Example 1 is followed, except that in step (1), the mixing temperature is changed to 150° C. and the mixing time is changed to 20 min;

[0092] The other steps are the same as those in Example 1, thereby obtaining modified polyurethane and polyurethane foam material.

[0093] Example 8

[0094] The method of Example 1 is followed, except that in step (2), the foaming molding conditions are changed to saturation at a temperature of 210° C. and a pressure of 5 MPa for 120 min;

[0095] The other steps are the same as those in Example 1, thereby obtaining modified polyurethane and polyurethane foam material.

[0096] Example 9

[0097] The method of Example 1 is followed, except that in step (1), the same amount of isooctyl acrylate grafted polypropylene is used instead of triallyl isocyanurate grafted polypropylene-I;

[0098] The other steps are the same as those in Example 1, thereby obtaining modified polyurethane and polyurethane foam material.

[0099] Example 10

[0100] The method of Example 1 is followed, except that in step (1), phenoxyaniline is replaced by the same amount of 3,4-diaminodiphenyl ether;

[0101] The other steps are the same as those in Example 1, thereby obtaining modified polyurethane and polyurethane foam material.

[0102] Embodiment 11

[0103] The method of Example 2 is followed, except that in step (1), the same amount of 1,10-decanediamine is used instead of 1,12-diaminododecane;

[0104] The other steps are the same as those in Example 2, thereby obtaining modified polyurethane and polyurethane foam material.

[0105] Example 12

[0106] The method of Example 4 is followed, except that the same amount of 1,3,5-triaminobenzene is used instead of p-phenylenediamine;

[0107] The other steps are the same as those in Example 4, thereby obtaining modified polyurethane and polyurethane foam material.

[0108] Comparative Example 1

[0109] The method of Example 1 is followed, except that triallyl isocyanurate-grafted polypropylene-I and phenoxyaniline are not added, specifically:

[0110] (1) 100 g of polyurethane was pressed into a sheet with a thickness of 2 mm, and dried at 90° C. for 30 min to obtain a polyurethane matrix;

[0111] (2) The polyurethane matrix is ​​placed in a high-pressure reactor, CO2 is introduced, and saturation is performed for 60 minutes at a temperature of 200°C and a pressure of 10 MPa. The temperature is then reduced to 140°C and the pressure is released to obtain a polyurethane foam material.

[0112] Comparative Example 2

[0113] The method of Example 1 is followed, except that in step (1), the amount of polyurethane is changed to 60 g; the amount of triallyl isocyanurate grafted polypropylene-I is changed to 35 g; and the amount of phenoxyaniline is changed to 5 g;

[0114] The other steps are the same as those in Example 1, thereby obtaining modified polyurethane and polyurethane foam material.

[0115] Comparative Example 3

[0116] The method of Example 1 is followed, except that triallyl isocyanurate-grafted polypropylene-I is not added, specifically:

[0117] (1) 85 g of polyurethane and 15 g of phenoxyaniline were mixed uniformly and added into an internal mixer, and kneaded for 5 min at a temperature of 200° C. and a rotation speed of 40 r / min. The obtained product was then pressed into a sheet with a thickness of 2 mm, and dried at 90° C. for 30 min to obtain a modified polyurethane;

[0118] (2) The modified polyurethane is placed in a high-pressure reactor, CO2 is introduced, and saturation is carried out for 60 minutes at a temperature of 200°C and a pressure of 10 MPa. The temperature is then reduced to 140°C and the pressure is released to obtain a polyurethane foam material.

[0119] Comparative Example 4

[0120] The method of Example 1 is followed, except that phenoxyaniline is not added, specifically:

[0121] (1) 85 g of polyurethane and 15 g of triallyl isocyanurate grafted polypropylene-I were mixed uniformly and added into an internal mixer, and kneaded for 5 min at a temperature of 200° C. and a rotation speed of 40 r / min. The resulting product was then pressed into a sheet with a thickness of 2 mm, and dried at 90° C. for 30 min to obtain a modified polyurethane;

[0122] (2) The modified polyurethane is placed in a high-pressure reactor, CO2 is introduced, and saturation is carried out for 60 minutes at a temperature of 200°C and a pressure of 10 MPa. The temperature is then reduced to 140°C and the pressure is released to obtain a polyurethane foam material.

[0123] Comparative Example 5

[0124] The method of Example 1 is followed, except that in step (1), the triallyl isocyanurate-grafted polypropylene-I is replaced with a mixture of triallyl isocyanurate (molecular weight 249 g / mol) and polypropylene (weight average molecular weight 550000 g / mol);

[0125] The other steps are the same as those in Example 1, thereby obtaining modified polyurethane and polyurethane foam material.

[0126] Test Example 1

[0127] The rheological properties of the modified polyurethanes prepared in step (1) of the above Examples 1-4 and the polyurethane matrix prepared in step (1) of Comparative Example 1 were measured at 190° C. using a rotational rheometer. The measurement results are as follows: Figure 1-4 shown.

[0128] Figure 1 The graph is a graph showing the variation of tanδ values ​​of the modified polyurethanes prepared in Examples 1 to 4 of the present invention and the polyurethane matrix prepared in Comparative Example 1 at 190°C with angular frequency. Figure 1It can be seen that the tanδ value of the modified polyurethanes prepared in Examples 1-4 in the low frequency region (angular frequency less than 1 rad / s) is significantly lower than the tanδ value of the polyurethane matrix prepared in Comparative Example 1 in the low frequency region (angular frequency less than 1 rad / s), and the reduction range is more than 40%, indicating that the modified polyurethane prepared in the present invention has better elasticity and higher melt strength, which is beneficial to the subsequent preparation of a polyurethane foam material with better foaming effect.

[0129] Figure 2 The graphs are the changes of complex viscosity of the modified polyurethanes prepared in Examples 1-4 and the polyurethane matrix prepared in Comparative Example 1 at 190°C as a function of angular frequency. Figure 2 It can be seen that the complex viscosity of the modified polyurethanes prepared in Examples 1-4 in the low frequency region (angular frequency less than 1 rad / s) is significantly increased relative to the complex viscosity of the polyurethane matrix prepared in Comparative Example 1 in the low frequency region (angular frequency less than 1 rad / s), and the increase is more than 50%; this indicates that the molecular weight of the modified polyurethane prepared in the present invention is increased, the molecular chain is longer, and the entanglement of the molecular chains makes the modified polyurethane more viscous, which is beneficial to the stable growth of the bubbles and more conducive to the formation of bubbles with smaller pore sizes, so that the foaming ratio of the subsequently prepared polyurethane foam material can be larger and the bubble density can be increased.

[0130] Figure 3 The storage modulus of the modified polyurethanes prepared in Examples 1 to 4 of the present invention and the polyurethane matrix prepared in Comparative Example 1 at 190° C. varies with angular frequency. Figure 3 It can be seen that the storage modulus of the modified polyurethanes prepared in Examples 1-4 in the low frequency region (angular frequency less than 1 rad / s) is greater than that of the polyurethane matrix prepared in Comparative Example 1 in the low frequency region (angular frequency less than 1 rad / s), and the increase is more than 40%, indicating that the modified polyurethane prepared in the present invention has better elasticity, which is beneficial to the subsequent preparation of a polyurethane foam material with a high foaming ratio and uniform pores.

[0131] Figure 4 The graph is a graph showing the change of the loss modulus of the modified polyurethanes prepared in Examples 1 to 4 of the present invention and the polyurethane matrix prepared in Comparative Example 1 at 190°C with angular frequency. Figure 4 It can be seen that the loss modulus of the modified polyurethanes prepared in Examples 1-4 in the low frequency region (angular frequency less than 1 rad / s) is significantly improved compared with the loss modulus of the polyurethane matrix prepared in Comparative Example 1 in the low frequency region (angular frequency less than 1 rad / s), and the improvement is more than 50%, indicating that the modified polyurethane prepared in the present invention has better viscoelastic properties, can reduce the merging and collapse of the cells, thereby enabling the subsequent preparation of a polyurethane foam material with a higher foaming ratio, a smaller cell diameter, and a higher cell density.

[0132] The variation of tanδ value, complex viscosity, storage modulus and loss modulus of the modified polyurethane prepared in the other embodiments in the low frequency region with angular frequency is shown in FIG. Figure 1-4 similar.

[0133] Test Example 2

[0134] The polyurethane foam materials prepared in the above examples and comparative examples were subjected to the following performance tests, and the results are listed in Table 1.

[0135] Table 1

[0136]

[0137]

[0138] It can be seen from the results of the embodiments, comparative examples and Table 1 that the polyurethane foam material prepared by the foamable polyurethane composition comprising polyurethane, polar monomer grafted polypropylene and amino compound of the present invention can obtain a higher foaming ratio of more than 9 times, the cell density is increased by one order of magnitude, and the average diameter of the cells is reduced to within the range of 50-80 μm, thereby having a better foaming effect.

[0139] Comparative Example 1 is a polyurethane foam material prepared without adding polar monomer grafted polypropylene and amino compound; Comparative Examples 3-4 are polyurethane foam materials prepared by reacting polyurethane only with amino compound or polar monomer grafted polypropylene; Comparative Example 2 is a polyurethane foam material prepared by using polyurethane, polar monomer grafted polypropylene and amino compound not within the ratio range specified in the present invention; Comparative Example 5 is a polyurethane foam material prepared by using a mixture of polar monomer and polypropylene instead of polar monomer grafted polypropylene. The polyurethane foam materials obtained in Comparative Examples 1-5 have a foaming ratio of only 4-6 times, a low cell density, a large average cell diameter, and cannot achieve a good foaming effect.

[0140] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A foamable polyurethane composition, characterized in that: The composition comprises polyurethane, polar monomer grafted polypropylene and amino compound, wherein the content of the polyurethane is 80-95wt%, the content of the polar monomer grafted polypropylene is 4-19wt%, and the content of the amino compound is 1-3wt% based on the total weight of the composition; The amino-containing compound is an organic substance containing an amino group, an ether bond and an aromatic group, wherein the C2-C 12 Alkanes or alkanes, C6-C 18 At least one of the aromatic hydrocarbons, wherein n is an integer of 2-5; the grafting degree of the polar monomer grafted polypropylene is 1-4wt%.

2. The composition according to claim 1, wherein The organic matter containing an amino group, an ether bond and an aromatic group is selected from at least one of phenoxyaniline, 3,3',4,4'-tetraaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 3,4-diaminodiphenyl ether, 2,4-bis(2-methylphenoxy)-aniline, 4-(2-methylphenoxy)aniline and 2-methyl-2'-aminodiphenyl ether; and / or, the n amino-substituted C2-C 12 The alkane or alkane is selected from at least one of 1,12-diaminododecane, 1,9-diaminononane, 1,6-hexanediamine, 1,10-decanediamine, diethylenetriamine, tetraethylenepentamine and pentamethyldiethylenetriamine; and / or, the n amino-substituted C6-C 18 The aromatic hydrocarbon is selected from at least one of p-phenylenediamine, m-phenylenediamine, o-phenylenediamine, 2,4-diaminododecylbenzene, diethyltoluenediamine, 1,3,5-triaminobenzene and 1,2,4,5-tetraaminobenzene.

3. The composition according to claim 2, wherein The organic substance containing an amino group, an ether bond and an aromatic group is at least one of phenoxyaniline, 3,3',4,4'-tetraaminodiphenyl ether and 2-methyl-2'-aminodiphenyl ether; and / or, the n amino-substituted C2-C 12 The alkane or alkane is at least one of 1,12-diaminododecane, 1,9-diaminononane, diethylenetriamine and 1,6-hexanediamine; and / or, the n amino-substituted C6-C 18 The aromatic hydrocarbon is p-phenylenediamine and / or 2,4-diaminododecylbenzene.

4. The composition according to claim 1 or 2, wherein The polar monomer in the polar monomer grafted polypropylene is selected from at least one of acrylic acid, methacrylic acid, methyl acrylate, methyl methacrylate, maleic anhydride, epoxy acrylate, triallyl isocyanurate, hydroxyethyl methacrylate, glycidyl methacrylate and isooctyl acrylate.

5. The composition according to claim 4, wherein The grafting degree of the polar monomer grafted onto polypropylene is 1.5-3wt%; And / or, the polar monomer in the polar monomer grafted polypropylene is at least one of triallyl isocyanurate, methyl acrylate, methacrylic acid and methyl methacrylate.

6. A method for preparing a modified polyurethane, characterized in that: The method comprises: mixing, tableting and drying the foamable polyurethane composition according to any one of claims 1 to 5 to obtain modified polyurethane.

7. The method according to claim 6, wherein: The mixing conditions include: temperature of 150-200°C and time of 2-20min; And / or, the drying conditions include: temperature of 60-100° C. and time of 10-60 min.

8. The method according to claim 7, wherein: The mixing conditions include: temperature of 180-200° C. and time of 2-10 min.

9. A modified polyurethane prepared by the method according to any one of claims 6 to 8, characterized in that: At 190° C., the tan δ value of the modified polyurethane in the low frequency region is reduced by more than 30% compared with the tan δ value of the polyurethane matrix in the low frequency region; and / or At 190° C., the complex viscosity of the modified polyurethane in the low frequency region is increased by more than 40% compared with the complex viscosity of the polyurethane matrix in the low frequency region; and / or At 190° C., the storage modulus of the modified polyurethane in the low frequency region is increased by more than 30% compared with the storage modulus of the polyurethane matrix in the low frequency region; and / or At 190° C., the loss modulus of the modified polyurethane in the low frequency region is increased by more than 40% compared with the loss modulus of the polyurethane matrix in the low frequency region; wherein, The polyurethane matrix is ​​obtained by tableting and drying polyurethane.

10. The modified polyurethane according to claim 9, wherein At 190° C., the tan δ value of the modified polyurethane in the low frequency region is reduced by more than 40% compared with the tan δ value of the polyurethane matrix in the low frequency region; and / or At 190° C., the complex viscosity of the modified polyurethane in the low frequency region is increased by more than 50% compared with the complex viscosity of the polyurethane matrix in the low frequency region; and / or At 190° C., the storage modulus of the modified polyurethane in the low frequency region is increased by more than 40% compared with the storage modulus of the polyurethane matrix in the low frequency region; and / or At 190° C., the loss modulus of the modified polyurethane in the low frequency region is increased by more than 50% compared with the loss modulus of the polyurethane matrix in the low frequency region.

11. A method for preparing a polyurethane foam material, characterized in that: The method comprises: in the presence of a foaming agent, foaming and molding the modified polyurethane according to claim 9 or 10, and then cooling the temperature to 110-150° C. to obtain a polyurethane foam material.

12. The method according to claim 11, wherein: The foaming molding conditions include: temperature of 180-210°C, pressure of 5-15MPa, and time of 30-120min; And / or, the foaming agent is selected from one of N2, CO2 and butane.

13. The method according to claim 12, wherein: The foaming molding conditions include: temperature of 180-200° C., pressure of 8-15 MPa, and time of 30-60 min.

14. A polyurethane foam material prepared by the method according to any one of claims 11 to 13, characterized in that: The foaming ratio of the polyurethane foam material is more than 9 times, the average diameter of the pores is 50-80 μm, and the pore density is (5-9.5)×10 7 Pieces / cm 3 .

15. The polyurethane foam material according to claim 14, wherein: The foaming ratio of the polyurethane foam material is 11-15 times, the average diameter of the pores is 50-70 μm, and the pore density is (6-9.5)×10 7 Pieces / cm 3 .

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