One-component polyurethane adhesive, its preparation method and use

Abstract

The application provides a single-component polyurethane adhesive as well as a preparation method and application thereof. The preparation raw materials of the single-component polyurethane adhesive include the following components: a polyurethane prepolymer A, a polyurethane prepolymer B, a plasticizer, a filler, carbon black, a water absorbent, a catalyst a and a catalyst b; the preparation raw materials of the polyurethane prepolymer A include a polyether polyol and a first isocyanate; and the preparation raw materials of the polyurethane prepolymer B include a small-molecule dihydric alcohol and a second isocyanate. The single-component polyurethane adhesive provided in the application has the characteristics of high modulus and high elongation.

Description

Technical Field

[0001] The present invention belongs to the technical field of polyurethane adhesives, and in particular relates to a one-component polyurethane adhesive and a preparation method and application thereof. Background Art

[0002] With the development of vehicle manufacturing technology and the improvement of glass production processes, sunroof glass has gradually been replaced by larger skylight glass. The connection between skylight glass and the car body is similar to the front and rear windshields and traditional sunroof glass. In most cases, single-component polyurethane adhesives are used. According to CAE analysis, with the increase in the modulus of single-component polyurethane adhesives, the torsional stiffness of passenger cars equipped with skylight glass can be improved by a certain proportion (2% to 5%). At the same time, the noise of the whole vehicle can also be reduced to a certain extent (2 to 4dB). Therefore, the development of single-component polyurethane adhesives with higher modulus has important practical significance and broad application prospects.

[0003] The tensile modulus (1% to 10% elongation) of single-component polyurethane adhesives currently on the market generally ranges from 1.0 to 3.0 MPa, making limited contributions to vehicle torsional stiffness and noise. While the addition of multifunctional isocyanates can increase the tensile modulus of single-component polyurethane adhesives, this can also lead to a rapid decrease in elongation at break.

[0004] CN110423592A discloses a two-component polyurethane adhesive and a preparation method thereof, wherein the two-component polyurethane adhesive is mainly composed of two components A and B, wherein the mass ratio of the two components A and B is 1:1; wherein the component A comprises 10wt% to 35wt% of castor oil polyol, 10wt% to 40wt% of polyester polyol, 5wt% to 30wt% of polyether polyol, 1wt% to 10wt% of hindered amine chain extender, 10wt% to 40wt% of plasticizer, 1wt% to 15wt% of modulus reducer, and no The two-component polyurethane adhesive comprises 30-60 wt% organic filler, 0.5-3 wt% coupling agent, 0.1-0.5 wt% catalyst, and 0.1-0.5 wt% thermosensitive catalyst; component B comprises 5-40 wt% liquefied diphenylmethane diisocyanate, 10-60 wt% polymethylene polyphenyl polyisocyanate, 20-40 wt% polyether polyol, 10-80 wt% inorganic filler, 1-10 wt% thixotropic agent, and 0.5-3 wt% water scavenger. The two-component polyurethane adhesive provided by this technical solution has the characteristics of rapid curing, high bonding strength, and can be used for bonding accessories with high seismic requirements, but its tensile modulus is still relatively low and needs to be further improved.

[0005] CN108587548A discloses a silane-terminated modified polycarbonate polyurethane adhesive resin, its preparation method, and application. The silane-terminated modified polycarbonate polyurethane adhesive resin is characterized by being obtained by reacting the following raw materials: (a) a polycarbonate resin having a glass transition temperature below 30°C, in an amount of 50 to 95 wt%, preferably 70 to 90 wt%, based on the weight of the resin; (b) a silane coupling agent with a primary amino group, in an amount of 4 to 45 wt%, preferably 9 to 29 wt%; and (c) a catalyst, in an amount of 0.1 to 10 wt%, preferably 0.2 to 1 wt%. The silane-terminated modified polycarbonate polyurethane adhesive resin has high modulus and strength, making it suitable for the preparation of automotive windshield adhesives. However, its shear strength is relatively low, and its tensile modulus still needs to be further improved.

[0006] Therefore, it is necessary to develop a one-component polyurethane adhesive with high modulus and high elongation. Summary of the Invention

[0007] In view of the shortcomings of the prior art, the present invention aims to provide a one-component polyurethane adhesive and its preparation method and application. The one-component polyurethane adhesive has the characteristics of high tensile shear strength, high modulus and high elongation.

[0008] To achieve this object, the present invention adopts the following technical solutions:

[0009] In a first aspect, the present invention provides a one-component polyurethane adhesive, wherein the raw materials for preparing the one-component polyurethane adhesive include the following components: polyurethane prepolymer A, polyurethane prepolymer B, plasticizer, filler, carbon black, water absorbent, catalyst a and catalyst b;

[0010] The raw materials for preparing the polyurethane prepolymer A include polyether polyol and a first isocyanate;

[0011] The raw materials for preparing the polyurethane prepolymer B include small molecule diol and second isocyanate.

[0012] In the present invention, the polyurethane prepolymer A and the polyurethane prepolymer B have a synergistic effect and are compounded with a plasticizer, a filler, carbon black, a water absorbent, a catalyst a, and a catalyst b. This allows the one-component polyurethane adhesive to achieve a high tensile modulus while ensuring basic mechanical properties (tensile shear strength ≥5 MPa, elongation at break ≥250%) and construction performance (extrudability of 10 g / min under a pressure of 0.4 MPa in a pressure flow viscometer with a 4 mm aperture).

[0013] Preferably, the molar ratio of the isocyanate group of the first isocyanate to the hydroxyl group of the polyether polyol in the raw materials for preparing the polyurethane prepolymer A is (2.1-2.5):1, for example, 2.15:1, 2.2:1, 2.25:1, 2.3:1, 2.35:1, 2.4:1 or 2.45:1.

[0014] In the present invention, the molar ratio of the isocyanate group to the hydroxyl group is expressed as NCO / OH.

[0015] Preferably, the polyether polyol is a polyether triol.

[0016] Preferably, the weight average molecular weight of the polyether polyol is 3000-6000 (eg, 3300, 3600, 3900, 4200, 4500, 4800, 5100, 5400 or 5700, etc.), more preferably 4500-5000.

[0017] In the present invention, the weight average molecular weight of the polyether polyol is more preferably 4500 to 5000. If the weight average molecular weight of the polyether polyol is too large, the tensile strength decreases and the elongation at break increases; if the weight average molecular weight of the polyether polyol is too small, the tensile strength increases but the elongation at break significantly decreases.

[0018] Preferably, the hydroxyl value of the polyether triol is 28 to 56 mgKOH / g (for example, 30 mgKOH / g, 33 mgKOH / g, 36 mgKOH / g, 39 mgKOH / g, 42 mgKOH / g, 45 mgKOH / g, 48 mgKOH / g, 51 mgKOH / g or 54 mgKOH / g, etc.), and more preferably 33.6 to 37.3 mgKOH / g.

[0019] Preferably, the first isocyanate and the second isocyanate each independently comprise an aromatic polyisocyanate and / or an aliphatic polyisocyanate.

[0020] Preferably, the aromatic polyisocyanate includes any one or a combination of at least two of toluene diisocyanate, diphenylmethane diisocyanate, 1,4-phenylene diisocyanate (PPDI), xylylene diisocyanate (XDI), tetramethylxylylene diisocyanate (TMXDI), toluidine diisocyanate (TODI) or 1,5-naphthalene diisocyanate (NDI).

[0021] Preferably, the toluene diisocyanate includes 2,4-toluene diisocyanate (2,4-TDI) and / or 2,6-toluene diisocyanate (2,6-TDI).

[0022] Preferably, the diphenylmethane diisocyanate includes 4,4'-diphenylmethane diisocyanate (4,4'-MDI) and / or 2,4'-diphenylmethane diisocyanate (2,4'-MDI).

[0023] Preferably, the aliphatic polyisocyanate includes any one or a combination of at least two of hexamethylene diisocyanate (HDI), trimethylhexamethylene diisocyanate (TMHDI), 1,5-pentamethylene diisocyanate (PDI), lysine diisocyanate (LDI), norbornane diisocyanate (NBDI), trans-cyclohexane-1,4-diisocyanate (TCDI), isophorone diisocyanate (IPDI), bis(isocyanatemethyl)cyclohexane (H6XDI) or dicyclohexylmethane diisocyanate (H12MDI).

[0024] Preferably, the first isocyanate is diphenylmethane diisocyanate, more preferably 4,4'-diphenylmethane diisocyanate.

[0025] Preferably, the second isocyanate is any one of xylylene diisocyanate, hexamethylene diisocyanate, lysine diisocyanate or 1,5-pentamethylene diisocyanate, or a combination of at least two thereof, more preferably xylylene diisocyanate.

[0026] Preferably, the preparation method of the polyurethane prepolymer A comprises the following steps: heating the polyether polyol to dehydrate, cooling the polyol, mixing the polyol with the first isocyanate and the catalyst C to react, thereby obtaining the polyurethane prepolymer A.

[0027] Preferably, the heating dehydration in the preparation method of polyurethane prepolymer A includes heating to 110-130°C (for example, 113°C, 116°C, 119°C, 122°C, 125°C or 128°C, etc.) under stirring and dehydrating for 1.5-2.5h (for example, 1.6h, 1.7h, 1.8h, 1.9h, 2.0h, 2.1h, 2.2h, 2.3h or 2.4h, etc.).

[0028] Preferably, the cooling in the preparation method of the polyurethane prepolymer A is cooling to 30-50° C. (eg, 33° C., 36° C., 39° C., 42° C., 45° C., or 48° C.).

[0029] Preferably, the reaction temperature in the preparation method of polyurethane prepolymer A is 75-90°C (for example, 77°C, 79°C, 81°C, 83°C, 85°C, 87°C or 89°C, etc.), and the reaction time is 2-6h (for example, 2.5h, 3h, 3.5h, 4h, 4.5h, 5h or 5.5h, etc.).

[0030] Preferably, the catalyst c comprises any one of dioctyltin dilaurate, dibutyltin dilaurate, dimethyltin dilaurate, stannous octoate, dibutyltin oxide or dioctyltin oxide, or a combination of at least two thereof.

[0031] Preferably, the mass of the catalyst c is 0.001% to 0.05% (e.g., 0.005%, 0.01%, 0.015%, 0.02%, 0.025%, 0.03%, 0.035%, 0.04% or 0.045%) of the total mass of the polyether polyol and the first isocyanate.

[0032] Preferably, the molar ratio of the isocyanate group of the second isocyanate to the hydroxyl group of the small molecule diol in the raw materials for preparing the polyurethane prepolymer B is (2.0-2.2):1, for example, 2.02:1, 2.04:1, 2.06:1, 2.08:1, 2.10:1, 2.12:1, 2.14:1, 2.16:1 or 2.18:1, etc.

[0033] Preferably, the small molecule diol includes a linear small molecule diol and / or a nonlinear small molecule diol, and more preferably a nonlinear small molecule diol.

[0034] In the present invention, the raw materials for preparing the polyurethane prepolymer B contain a relatively high content of isocyanate, which provides a higher modulus. At the same time, the addition of nonlinear small molecule diols enables the polyurethane prepolymer B to maintain a high modulus while also improving toughness compared to the use of linear small molecule diols.

[0035] Preferably, the linear small molecule diol includes any one or a combination of at least two of ethylene glycol, 1,4-butanediol, 1,6-hexanediol, bisphenol A or bisphenol-propylene oxide adduct.

[0036] Preferably, the nonlinear small molecule diol includes any one of 2-methyl-1,3-propanediol, 2-methyl-2,4-pentanediol, 2-ethyl-1,3-ethanediol or 2-ethyl-1,3-hexanediol, or a combination of at least two thereof, and more preferably 2-ethyl-1,3-hexanediol.

[0037] Preferably, the preparation method of the polyurethane prepolymer B comprises the following steps: heating and dehydrating a small molecule diol, cooling the mixture, mixing the mixture with a second isocyanate, and reacting the mixture to obtain the polyurethane prepolymer B.

[0038] Preferably, the heating dehydration in the preparation method of the polyurethane prepolymer B includes heating to 110-130°C (for example, 113°C, 116°C, 119°C, 122°C, 125°C or 128°C, etc.) under stirring and dehydrating for 1.5-2.5h (for example, 1.6h, 1.7h, 1.8h, 1.9h, 2.0h, 2.1h, 2.2h, 2.3h or 2.4h, etc.).

[0039] Preferably, the cooling in the preparation method of the polyurethane prepolymer B is cooling to 30-50° C. (eg, 33° C., 36° C., 39° C., 42° C., 45° C., or 48° C.).

[0040] Preferably, the reaction temperature in the preparation method of polyurethane prepolymer B is 75-90°C (for example, 77°C, 79°C, 81°C, 83°C, 85°C, 87°C or 89°C, etc.), and the reaction time is 2-6h (for example, 2.5h, 3h, 3.5h, 4h, 4.5h, 5h or 5.5h, etc.).

[0041] Preferably, the plasticizer includes any one of alkyl sulfonate, phthalate, tricresyl phosphate or trioctyl phosphate, or a combination of at least two thereof, and more preferably phthalate.

[0042] Preferably, the plasticizer is a plasticizer obtained by vacuum dehydration at 110-130°C (e.g., 113°C, 116°C, 119°C, 122°C, 125°C or 128°C, etc.) for 1.5-2.5h (e.g., 1.6h, 1.7h, 1.8h, 1.9h, 2.0h, 2.1h, 2.2h, 2.3h or 2.4h, etc.).

[0043] Preferably, the phthalate includes any one or a combination of at least two of dioctyl phthalate (DOP), butylbenzene phthalate (DBP), diisooctyl phthalate (DIOP), diisodecyl phthalate (DIDP) or diisononyl phthalate (DINP), more preferably diisodecyl phthalate.

[0044] Preferably, the filler comprises any one or a combination of at least two of silicon dioxide, heavy calcium carbonate, talc, clay, organic bentonite, hydrogenated castor oil or barium sulfate.

[0045] Preferably, the carbon black includes any one of gas furnace carbon black, oil furnace carbon black, oil-gas furnace carbon black, thermal cracking carbon black or acetylene carbon black, or a combination of at least two thereof.

[0046] Preferably, the water absorbent comprises any one of alkylsulfonic acid isocyanate, calcium oxide or molecular sieve, or a combination of at least two thereof.

[0047] Preferably, the catalyst a comprises an organotin metal catalyst and / or an organobismuth metal catalyst.

[0048] Preferably, the organotin metal catalyst includes any one of dioctyltin dilaurate, dibutyltin dilaurate, dimethyltin dilaurate, dioctyltin dimaleate, dibutyltin dimaleate, dimethyltin dimaleate, dioctyltin dithiol, dibutyltin dithiol, dimethyltin dithiol, stannous octoate, butyltin oxide or octyltin oxide, or a combination of at least two thereof.

[0049] Preferably, the organic bismuth metal catalyst includes any one of bismuth neodecanoate, bismuth laurate, bismuth isooctanoate or bismuth naphthenate, or a combination of at least two thereof.

[0050] Preferably, the catalyst b comprises a tertiary amine catalyst.

[0051] Preferably, the tertiary amine catalyst includes any one or a combination of at least two of N,N-dimethylcyclohexylamine, bis(2-dimethylaminoethyl) ether, bismorpholine diethyl ether, N,N,N',N'-tetramethylalkylenediamine, triethylamine or N,N-dimethylbenzylamine.

[0052] Preferably, the raw materials for preparing the one-component polyurethane adhesive include the following components in parts by weight: 30-45 parts of polyurethane prepolymer A (for example, 32 parts, 34 parts, 36 parts, 38 parts, 40 parts, 42 parts or 44 parts), 3-5 parts of polyurethane prepolymer B (for example, 3.2 parts, 3.4 parts, 3.6 parts, 3.8 parts, 4 parts, 4.2 parts, 4.4 parts, 4.6 parts or 4.8 parts), 15-25 parts of plasticizer (for example, 16 parts, 17 parts, 18 parts, 19 parts, 20 parts, 21 parts, 22 parts, 23 parts or 24 parts), 10 parts of filler ~20 parts (for example, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts, 18 parts or 19 parts, etc.), carbon black 15-25 parts (for example, 16 parts, 17 parts, 18 parts, 19 parts, 20 parts, 21 parts, 22 parts, 23 parts or 24 parts, etc.), water absorbent 0.1-1 part (for example, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts or 0.9 parts, etc.), catalyst a 0.01 to 1 part (e.g., 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8 or 0.9 part, etc.) and catalyst b 0.01 to 1 part (e.g., 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8 or 0.9 part, etc.).

[0053] In a second aspect, the present invention provides a method for preparing the one-component polyurethane adhesive as described in the first aspect, the preparation method comprising the following steps: mixing polyurethane prepolymer A, polyurethane prepolymer B, a plasticizer, a filler, carbon black, a water absorbent, a catalyst a and a catalyst b to obtain the one-component polyurethane adhesive.

[0054] Preferably, the moisture content in the filler is ≤1000 ppm, for example, 300 ppm, 400 ppm, 500 ppm, 600 ppm, 700 ppm, 800 ppm or 900 ppm.

[0055] Preferably, the moisture content in the carbon black is ≤1000 ppm, for example, 300 ppm, 400 ppm, 500 ppm, 600 ppm, 700 ppm, 800 ppm or 900 ppm.

[0056] Preferably, the preparation method specifically comprises the following steps: first mixing polyurethane prepolymer A, polyurethane prepolymer B, plasticizer, filler, carbon black and water absorbent under vacuum conditions, and secondly adding catalyst a and catalyst b to mix to obtain the one-component polyurethane adhesive.

[0057] Preferably, the vacuum degree of the vacuum condition is -1000 to -950 mbar, for example, -995 mbar, -990 mbar, -985 mbar, -980 mbar, -975 mbar, -970 mbar, -965 mbar, -960 mbar or -955 mbar.

[0058] In a third aspect, the present invention provides a use of the one-component polyurethane adhesive as described in the first aspect in bonding skylight glass.

[0059] Compared with the prior art, the present invention has the following beneficial effects:

[0060] In the present invention, the one-component polyurethane adhesive prepared by compounding the polyurethane prepolymer A, polyurethane prepolymer B, plasticizer, filler, carbon black, water absorbent, catalyst A, and catalyst B exhibits high modulus and elongation while maintaining basic mechanical properties and workability. The one-component polyurethane adhesive has a tensile modulus of 9.5 MPa or greater, a tensile strength of 8.6 MPa or greater, an elongation at break of 250% or greater, and a tensile shear strength of 5.6 MPa or greater. DETAILED DESCRIPTION

[0061] The technical solution of the present invention is further described below by way of specific embodiments. It should be understood by those skilled in the art that the embodiments are merely to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0062] The sources of some raw materials in the preparation examples, embodiments and comparative examples are as follows:

[0063] Polyether triol: The average weight-average molecular weight is 4600 and it comes from Yantai Wanhua Chemical Group;

[0064] Polyether triol: The average weight-average molecular weight is 6000 and it comes from Yantai Wanhua Chemical Group;

[0065] 2-Ethyl-1,3-hexanediol, from Jiangsu Runfeng Synthetic Technology Co., Ltd.;

[0066] 4,4'-diphenylmethane diisocyanate, MDI-50, from Yantai Wanhua Chemical Group;

[0067] xylylene diisocyanate, from Mitsui Chemicals;

[0068] Diisononyl phthalate, from ExxonMobil (China) Co., Ltd.;

[0069] Filler: Clay B-95, from Shanxi Jinyu Kelin Technology Co., Ltd.

[0070] Carbon black: M-580 from Cabot;

[0071] Water absorbent: TI, from Bayer;

[0072] Catalyst a: bismorpholine diethyl ether, from Air Products and Chemicals, USA;

[0073] Catalyst b: UL-29, from Maitu High-Tech Materials.

[0074] Preparation Example 1

[0075] This preparation example provides a polyurethane prepolymer A, specifically polyurethane prepolymer A1, which is prepared by the following method:

[0076] The polyether triol ( The average weight-average molecular weight is 4600) 1500g, heated to 130 ° C for dehydration for 2 hours, then cooled to 50 ° C, added with the first isocyanate (4,4'-diphenylmethane diisocyanate) 258g (at this time NCO / OH = 2.2), dioctyltin dilaurate 0.82g, mixed, heated to 85 ° C for reaction for 2h, the tested NCO content reached 2.69%, cooled to 50 ° C, and obtained the polyurethane prepolymer A1.

[0077] Preparation Example 2

[0078] This preparation example provides a polyurethane prepolymer A, specifically polyurethane prepolymer A2, which is prepared by the following method:

[0079] The polyether triol ( The average weight-average molecular weight is 6000) 1500g, heated to 130 ° C for dehydration for 2 hours, then cooled to 50 ° C, added with the first isocyanate (4,4'-diphenylmethane diisocyanate) 206g (at this time NCO / OH = 2.2), dioctyltin dilaurate 0.82g, mixed, heated to 85 ° C for reaction 2h, the tested NCO content reached 2.21%, cooled to 50 ° C, and obtained the polyurethane prepolymer A2.

[0080] Preparation Example 3

[0081] This preparation example provides a polyurethane prepolymer A, specifically polyurethane prepolymer A3, which is prepared by the following method:

[0082] The polyether triol ( The average weight-average molecular weight is 4600) 1500g, heated to 130 ° C for dehydration for 2 hours, then cooled to 50 ° C, added with the first isocyanate (hexamethylene diisocyanate) 173g (at this time NCO / OH = 2.2), dioctyltin dilaurate 0.82g, mixed, heated to 85 ° C for 2h, and the NCO content to be tested reached 2.81%, and then cooled to 50 ° C to obtain the polyurethane prepolymer A3.

[0083] Preparation Example 4

[0084] This preparation example provides a polyurethane prepolymer B, specifically polyurethane prepolymer B1, which is prepared by the following method:

[0085] 500 g of a small molecule diol (2-ethyl-1,3-hexanediol) was heated to 130° C. for dehydration for 2 hours, then cooled to 50° C. and added with 1350 g of a second isocyanate (xylylene diisocyanate) (NCO / OH = 2.1 at this time). After mixing, the temperature was raised to 85° C. for reaction for 2 hours. When the tested NCO content reached 17.30%, the temperature was lowered to 50° C. to obtain the polyurethane prepolymer B1.

[0086] Preparation Example 5

[0087] This preparation example provides a polyurethane prepolymer B, specifically polyurethane prepolymer B2, which is prepared by the following method:

[0088] 500 g of a small molecule diol (2-ethyl-1,3-hexanediol) was heated to 130° C. for dehydration for 2 hours, then cooled to 50° C. and added with 1110 g of a second isocyanate (1,5-pentane diisocyanate) (NCO / OH = 2.1 at this time). After mixing, the temperature was raised to 85° C. for reaction for 2 hours. When the tested NCO content reached 19.7%, the temperature was lowered to 50° C. to obtain the polyurethane prepolymer B2.

[0089] Preparation Example 6

[0090] This preparation example provides a polyurethane prepolymer B, specifically polyurethane prepolymer B3, which is prepared by the following method:

[0091] 500 g of a small molecule diol (2-methyl-1,3-propanediol) was heated to 130° C. for dehydration for 2 hours, then cooled to 50° C. and added with 1478 g of a second isocyanate (xylene diisocyanate) (NCO / OH = 2.1 at this time). After mixing, the temperature was raised to 85° C. and reacted for 2 hours. When the tested NCO content reached 18.6%, the temperature was lowered to 50° C. to obtain the polyurethane prepolymer B3.

[0092] Preparation Example 7

[0093] This preparation example provides a polyurethane prepolymer B, specifically polyurethane prepolymer B4, which is prepared by the following method:

[0094] 500 g of a small molecule diol (1,6-hexanediol) was heated to 130° C. for dehydration for 2 hours, then cooled to 50° C. and added with 1673 g of a second isocyanate (xylene diisocyanate) (NCO / OH = 2.1 at this time). After mixing, the temperature was raised to 85° C. for reaction for 2 hours. When the tested NCO content reached 18.0%, the temperature was lowered to 50° C. to obtain the polyurethane prepolymer B4.

[0095] Example 1

[0096] This embodiment provides a one-component polyurethane adhesive and a preparation method thereof. The raw materials for preparing the one-component polyurethane adhesive include the following components in parts by weight: 40 parts of the polyurethane prepolymer A1 provided in Preparation Example 1, 4 parts of the polyurethane prepolymer B1 provided in Preparation Example 4, 20 parts of a plasticizer (diisononyl phthalate), 15 parts of a filler (clay B-95), 20 parts of carbon black (M-580), 0.5 parts of a water absorbent (TI), 0.1 parts of a catalyst a (bismorpholine diethyl ether), and 0.02 parts of a catalyst b (UL-29).

[0097] The preparation method comprises the following steps:

[0098] The polyurethane prepolymer A1 provided in Preparation Example 1, the polyurethane prepolymer B1 provided in Preparation Example 4, a plasticizer, a filler, carbon black and a water absorbent were mixed under vacuum conditions (vacuum degree of 980 mbar), and then catalysts a and b were added and stirred evenly to obtain the one-component polyurethane adhesive.

[0099] The above plasticizer is a plasticizer obtained by vacuum dehydration at 110°C for 2 hours;

[0100] The filler was dried in an oven at 120°C for 7 days and had a moisture content of 800 ppm.

[0101] The carbon black was dried in an oven at 120°C for 7 days and had a moisture content of 800 ppm.

[0102] Example 2

[0103] This embodiment provides a one-component polyurethane adhesive and a preparation method thereof. The only difference between this embodiment and Example 1 is that the weight fraction of the polyurethane prepolymer B1 provided in Preparation Example 4 is adjusted to 3 parts, and other conditions are the same as those in Example 1.

[0104] Example 3

[0105] This embodiment provides a one-component polyurethane adhesive and a preparation method thereof. The only difference between the one-component polyurethane adhesive and Example 1 is that the raw materials for preparing the one-component polyurethane adhesive include the following components in parts by weight: 45 parts of the polyurethane prepolymer A1 provided in Preparation Example 1, 3 parts of the polyurethane prepolymer B1 provided in Preparation Example 4, 15 parts of a plasticizer (diisononyl phthalate), 15 parts of a filler (clay B-95), 20 parts of carbon black (M-580), 0.5 parts of a water absorbent (TI), 0.1 parts of a catalyst a (bismorpholine diethyl ether), and 0.02 parts of a catalyst b (UL-29). Other conditions are the same as in Example 1.

[0106] Example 4

[0107] This embodiment provides a one-component polyurethane adhesive and a preparation method thereof. The only difference between the one-component polyurethane adhesive and Example 1 is that the raw materials for preparing the one-component polyurethane adhesive include the following components in parts by weight: 30 parts of the polyurethane prepolymer A1 provided in Preparation Example 1, 5 parts of the polyurethane prepolymer B1 provided in Preparation Example 4, 20 parts of a plasticizer (diisononyl phthalate), 20 parts of a filler (clay B-95), 25 parts of carbon black (M-580), 0.5 parts of a water absorbent (TI), 0.1 parts of a catalyst a (bismorpholine diethyl ether), and 0.02 parts of a catalyst b (UL-29). Other conditions are the same as in Example 1.

[0108] Example 5

[0109] This embodiment provides a one-component polyurethane adhesive and a preparation method thereof. The only difference between the one-component polyurethane adhesive and Example 1 is that the raw materials for preparing the one-component polyurethane adhesive include the following components in parts by weight: 35 parts of the polyurethane prepolymer A1 provided in Preparation Example 1, 5 parts of the polyurethane prepolymer B1 provided in Preparation Example 4, 20 parts of a plasticizer (diisononyl phthalate), 20 parts of a filler (clay B-95), 20 parts of carbon black (M-580), 0.5 parts of a water absorbent (TI), 0.1 parts of a catalyst a (bismorpholine diethyl ether), and 0.02 parts of a catalyst b (UL-29). Other conditions are the same as in Example 1.

[0110] Example 6

[0111] This embodiment provides a one-component polyurethane adhesive and a preparation method thereof. The only difference between this embodiment and Example 1 is that the polyurethane prepolymer A1 provided in Preparation Example 1 is replaced with the polyurethane prepolymer A2 provided in Preparation Example 2 of the same mass. Other conditions are the same as in Example 1.

[0112] Example 7

[0113] This embodiment provides a one-component polyurethane adhesive and a preparation method thereof. The only difference between this embodiment and Example 1 is that the polyurethane prepolymer A1 provided in Preparation Example 1 is replaced with the polyurethane prepolymer A3 provided in Preparation Example 3 of the same mass. Other conditions are the same as in Example 1.

[0114] Example 8

[0115] This embodiment provides a one-component polyurethane adhesive and a preparation method thereof. The only difference between this embodiment and Example 1 is that the polyurethane prepolymer B1 provided in Preparation Example 1 is replaced with the polyurethane prepolymer B2 provided in Preparation Example 5 of the same mass. Other conditions are the same as in Example 1.

[0116] Example 9

[0117] This embodiment provides a one-component polyurethane adhesive and a preparation method thereof. The only difference between this embodiment and Example 1 is that the polyurethane prepolymer B1 provided in Preparation Example 1 is replaced with the polyurethane prepolymer B3 provided in Preparation Example 6 of the same mass. Other conditions are the same as in Example 1.

[0118] Example 10

[0119] This embodiment provides a one-component polyurethane adhesive and a preparation method thereof. The only difference between this embodiment and Example 1 is that the polyurethane prepolymer B1 provided in Preparation Example 1 is replaced with the polyurethane prepolymer B4 provided in Preparation Example 7 of the same mass. Other conditions are the same as in Example 1.

[0120] Example 11

[0121] This embodiment provides a one-component polyurethane adhesive and a preparation method thereof. The only difference between this embodiment and Example 1 is that the weight fraction of the polyurethane prepolymer A1 provided in Preparation Example 1 is adjusted to 25 parts, and other conditions are the same as those in Example 1.

[0122] Example 12

[0123] This embodiment provides a one-component polyurethane adhesive and a preparation method thereof. The only difference between this embodiment and Example 1 is that the weight fraction of the polyurethane prepolymer A1 provided in Preparation Example 1 is adjusted to 50 parts, and other conditions are the same as those in Example 1.

[0124] Comparative Example 1

[0125] This comparative example provides a one-component polyurethane adhesive and a preparation method thereof, which differs from Example 1 only in that the polyurethane prepolymer B1 provided in Preparation Example 4 is replaced with a polyisocyanate (HDI trimer) of the same mass, and other conditions are the same as in Example 1.

[0126] Comparative Example 2

[0127] This comparative example provides a one-component polyurethane adhesive and a preparation method thereof, which differs from Example 6 only in that the polyurethane prepolymer B1 provided in Preparation Example 4 is replaced with a polyisocyanate (HDI trimer) of the same mass, and other conditions are the same as Example 6.

[0128] The one-component polyurethane adhesives provided in Examples 1 to 12 and Comparative Examples 1 to 2 were tested as follows: tensile strength, elongation at break, and tensile shear strength were tested according to the method in standard HG / T 4363-2012 One-component polyurethane adhesives for automotive window glass. The tensile modulus was obtained by taking the slope of the tensile curve at an elongation of 1% to 10% during the tensile strength and elongation at break tests.

[0129] The test results are shown in Table 1 below:

[0130] Table 1

[0131]

[0132]

[0133] As can be seen from the contents of Table 1, the one-component polyurethane adhesive provided by Examples 1-12 has a tensile modulus of 9.5 to 11.5 MPa, a tensile strength of 8.6 to 11.2 MPa, an elongation at break of 250% to 370%, and a tensile shear strength of 5.6 to 6.2 MPa, and has the characteristics of high modulus and high elongation.

[0134] Compared with Example 1, if the polyurethane prepolymer A1 provided in Preparation Example 1 is replaced by the polyurethane prepolymer A2 provided in Preparation Example 2 of the same mass (Example 6), the tensile modulus and tensile strength of the prepared one-component polyurethane adhesive decrease. It can be seen that the performance of the one-component polyurethane adhesive prepared when the weight average molecular weight of the polyether polyol is preferably 4500-5000 is better.

[0135] Compared with Example 1, if the polyurethane prepolymer A1 provided in Preparation Example 1 is replaced by the polyurethane prepolymer A3 provided in Preparation Example 3 of the same mass (Example 7), the various indicators of the prepared one-component polyurethane adhesive are lower. It can be seen that the performance of the one-component polyurethane adhesive prepared by preferably using 4,4'-diphenylmethane diisocyanate as the first isocyanate is better.

[0136] Compared with Example 1, if the polyurethane prepolymer B1 provided in Preparation Example 1 is replaced with the polyurethane prepolymer B2 provided in Preparation Example 5 of the same mass (Example 8), the various indicators of the prepared one-component polyurethane adhesive are lower. It can be seen that the performance of the one-component polyurethane adhesive prepared by preferably using xylene diisocyanate as the second isocyanate is better.

[0137] Compared with Example 1, if the polyurethane prepolymer B1 provided in Preparation Example 1 is replaced with the polyurethane prepolymer B3 provided in Preparation Example 6 of the same mass (Example 9), the various indicators of the prepared one-component polyurethane adhesive are slightly reduced. It can be seen that the performance of the one-component polyurethane adhesive prepared by the nonlinear small molecule diol preferably being 2-ethyl-1,3-hexanediol is better.

[0138] Compared with Example 1, if the polyurethane prepolymer B1 provided in Preparation Example 1 is replaced with the polyurethane prepolymer B4 provided in Preparation Example 7 of the same mass (Example 10), the elongation at break of the prepared one-component polyurethane adhesive is greatly reduced. It can be seen that the performance of the one-component polyurethane adhesive prepared by the small molecule diol is preferably a nonlinear small molecule diol.

[0139] Compared with Example 1, if the weight fraction of polyurethane prepolymer A1 is too low (Example 11), the tensile modulus and tensile strength of the prepared one-component polyurethane adhesive increase, but the elongation at break decreases significantly; if the weight fraction of polyurethane prepolymer A1 is too high (Example 12), the elongation at break of the prepared one-component polyurethane adhesive increases, but the tensile modulus and tensile strength decrease significantly. It can be seen that the one-component polyurethane adhesive prepared with a weight fraction of polyurethane prepolymer A of 30 to 45 parts has better performance.

[0140] Compared to Example 1, if the polyurethane prepolymer B1 provided in Preparation Example 4 was replaced with a polyisocyanate of the same mass (Comparative Example 1), the tensile modulus, tensile strength, elongation at break, and tensile shear strength of the resulting one-component polyurethane adhesive were all reduced. Compared to Example 6, if the polyurethane prepolymer B1 provided in Preparation Example 4 was replaced with a polyisocyanate of the same mass (Comparative Example 2), the tensile modulus, tensile strength, elongation at break, and tensile shear strength of the resulting one-component polyurethane adhesive were all reduced. This indicates that the one-component polyurethane adhesive prepared by compounding polyurethane prepolymer A and polyurethane prepolymer B exhibits superior performance.

[0141] The applicant declares that the present invention uses the above-described embodiments to illustrate the one-component polyurethane adhesive, its preparation method, and its application. However, the present invention is not limited to the above-described embodiments, nor does it necessarily rely on the above-described embodiments for implementation. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions for raw materials in the present invention, addition of auxiliary components, and selection of specific methods, etc., fall within the scope of protection and disclosure of the present invention.

Claims

1. A one-component polyurethane adhesive, characterized in that: The raw materials for preparing the one-component polyurethane adhesive include the following components in parts by weight: 30-45 parts of polyurethane prepolymer A, 3-5 parts of polyurethane prepolymer B, 15-25 parts of plasticizer, 10-20 parts of filler, 15-25 parts of carbon black, 0.1-1 part of water absorbent, 0.01-1 part of catalyst a and 0.01-1 part of catalyst b; The raw materials for preparing the polyurethane prepolymer A include polyether polyol and a first isocyanate; The raw materials for preparing the polyurethane prepolymer B include small molecule diol and second isocyanate; The catalyst a includes an organic tin metal catalyst and / or an organic bismuth metal catalyst; The catalyst b includes a tertiary amine catalyst.

2. The one-component polyurethane adhesive according to claim 1, characterized in that The molar ratio of the isocyanate group of the first isocyanate to the hydroxyl group of the polyether polyol in the raw materials for preparing the polyurethane prepolymer A is (2.1-2.5):

1.

3. The one-component polyurethane adhesive according to claim 1, characterized in that The polyether polyol is a polyether triol.

4. The one-component polyurethane adhesive according to claim 1, characterized in that The weight average molecular weight of the polyether polyol is 3000-6000.

5. The one-component polyurethane adhesive according to claim 1, characterized in that The weight average molecular weight of the polyether polyol is 4500-5000.

6. The one-component polyurethane adhesive according to claim 3, characterized in that: The hydroxyl value of the polyether triol is 28-56 mgKOH / g.

7. The one-component polyurethane adhesive according to claim 1, characterized in that: The first isocyanate and the second isocyanate each independently include aromatic polyisocyanate and / or aliphatic polyisocyanate.

8. The one-component polyurethane adhesive according to claim 7, characterized in that: The aromatic polyisocyanate includes any one or a combination of at least two of toluene diisocyanate, diphenylmethane diisocyanate, 1,4-phenylene diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, toluidine diisocyanate or 1,5-naphthalene diisocyanate.

9. The one-component polyurethane adhesive according to claim 8, characterized in that: The toluene diisocyanate includes 2,4-toluene diisocyanate and / or 2,6-toluene diisocyanate.

10. The one-component polyurethane adhesive according to claim 8, characterized in that: The diphenylmethane diisocyanate includes 4,4'-diphenylmethane diisocyanate and / or 2,4'-diphenylmethane diisocyanate.

11. The one-component polyurethane adhesive according to claim 7, characterized in that: The aliphatic polyisocyanate includes any one or a combination of at least two of hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, 1,5-pentamethylene diisocyanate, lysine diisocyanate, norbornane diisocyanate, trans-cyclohexane-1,4-diisocyanate, isophorone diisocyanate, bis(isocyanatomethyl)cyclohexane or dicyclohexylmethane diisocyanate.

12. The one-component polyurethane adhesive according to claim 1 or 2, characterized in that: The preparation method of the polyurethane prepolymer A comprises the following steps: heating and dehydrating a polyether polyol, cooling the polyol, mixing the polyol with a first isocyanate and a catalyst C to react, and obtaining the polyurethane prepolymer A.

13. The one-component polyurethane adhesive according to claim 12, characterized in that: The heating dehydration in the preparation method of the polyurethane prepolymer A includes heating to 110-130° C. for dehydration for 1.5-2.5 hours under stirring.

14. The one-component polyurethane adhesive according to claim 12, characterized in that: The cooling in the preparation method of polyurethane prepolymer A is cooling to 30-50°C.

15. The one-component polyurethane adhesive according to claim 12, characterized in that: The reaction temperature in the preparation method of polyurethane prepolymer A is 75-90° C. and the reaction time is 2-6 h.

16. The one-component polyurethane adhesive according to claim 12, characterized in that: The catalyst c includes any one of dioctyltin dilaurate, dibutyltin dilaurate, dimethyltin dilaurate, stannous octoate, dibutyltin oxide or dioctyltin oxide, or a combination of at least two thereof.

17. The one-component polyurethane adhesive according to claim 12, characterized in that: The mass of the catalyst c is 0.001% to 0.05% of the total mass of the polyether polyol and the first isocyanate.

18. The one-component polyurethane adhesive according to claim 1, characterized in that The molar ratio of the isocyanate group of the second isocyanate to the hydroxyl group of the small molecule diol in the raw materials for preparing the polyurethane prepolymer B is (2.0-2.2):

1.

19. The one-component polyurethane adhesive according to claim 1, characterized in that: The small molecule diols include linear small molecule diols and / or nonlinear small molecule diols.

20. The one-component polyurethane adhesive according to claim 1, characterized in that The small molecule diol is a nonlinear small molecule diol.

21. The one-component polyurethane adhesive according to claim 19, characterized in that The linear small molecule diol includes any one of ethylene glycol, 1,4-butanediol, 1,6-hexanediol, bisphenol A or bisphenol-propylene oxide adduct, or a combination of at least two thereof.

22. The one-component polyurethane adhesive according to claim 19, characterized in that The nonlinear small molecule diol includes any one of 2-methyl-1,3-propanediol, 2-methyl-2,4-pentanediol and 2-ethyl-1,3-hexanediol, or a combination of at least two thereof.

23. The one-component polyurethane adhesive according to claim 19, characterized in that The nonlinear small molecule diol is 2-ethyl-1,3-hexanediol.

24. The one-component polyurethane adhesive according to claim 1, characterized in that The preparation method of the polyurethane prepolymer B comprises the following steps: heating and dehydrating a small molecule diol, cooling the diol, mixing the diol with a second isocyanate, and reacting the mixture to obtain the polyurethane prepolymer B.

25. The one-component polyurethane adhesive according to claim 24, characterized in that The heating dehydration in the preparation method of the polyurethane prepolymer B includes heating to 110-130° C. for dehydration for 1.5-2.5 hours under stirring.

26. The one-component polyurethane adhesive according to claim 24, characterized in that The cooling in the preparation method of polyurethane prepolymer B is cooling to 30-50°C.

27. The one-component polyurethane adhesive according to claim 24, characterized in that In the preparation method of polyurethane prepolymer B, the reaction temperature is 75-90° C., and the reaction time is 2-6 h.

28. The one-component polyurethane adhesive according to claim 1, characterized in that The plasticizer includes any one of alkyl sulfonate, phthalate, tricresyl phosphate or trioctyl phosphate, or a combination of at least two thereof.

29. The one-component polyurethane adhesive according to claim 1, characterized in that The plasticizer is phthalate.

30. The one-component polyurethane adhesive according to claim 1, characterized in that The plasticizer is obtained by vacuum dehydration at 110-130° C. for 1.5-2.5 hours.

31. The one-component polyurethane adhesive according to claim 29, characterized in that The phthalate ester includes any one of dioctyl phthalate, butyl phthalate, diisooctyl phthalate, diisodecyl phthalate or diisononyl phthalate, or a combination of at least two of them.

32. The one-component polyurethane adhesive according to claim 29, characterized in that The phthalate ester is diisodecyl phthalate.

33. The one-component polyurethane adhesive according to claim 1, characterized in that The filler includes any one of silicon dioxide, heavy calcium carbonate, talc, clay, organic bentonite, hydrogenated castor oil or barium sulfate, or a combination of at least two thereof.

34. The one-component polyurethane adhesive according to claim 1, characterized in that The carbon black includes any one of gas furnace carbon black, oil furnace carbon black, oil-gas furnace carbon black, thermal cracking carbon black or acetylene carbon black, or a combination of at least two thereof.

35. The one-component polyurethane adhesive according to claim 1, characterized in that The water absorbing agent includes any one of alkylsulfonic acid isocyanate, calcium oxide or molecular sieve, or a combination of at least two of them.

36. The one-component polyurethane adhesive according to claim 1, characterized in that The organotin metal catalyst includes any one of dioctyltin dilaurate, dibutyltin dilaurate, dimethyltin dilaurate, dioctyltin dimaleate, dibutyltin dimaleate, dimethyltin dimaleate, dioctyltin dithiol, dibutyltin dithiol, dimethyltin dithiol, stannous octoate, butyltin oxide or octyltin oxide, or a combination of at least two thereof.

37. The one-component polyurethane adhesive according to claim 1, characterized in that The organic bismuth metal catalyst includes any one of bismuth neodecanoate, bismuth laurate, bismuth isooctanoate or bismuth naphthenate, or a combination of at least two thereof.

38. The one-component polyurethane adhesive according to claim 1, characterized in that The tertiary amine catalyst includes any one of N,N-dimethylcyclohexylamine, bis(2-dimethylaminoethyl) ether, bismorpholine diethyl ether, N,N,N',N'-tetramethylalkylenediamine, triethylamine or N,N-dimethylbenzylamine, or a combination of at least two thereof.

39. A method for preparing the one-component polyurethane adhesive according to any one of claims 1 to 38, characterized in that: The preparation method comprises the following steps: mixing polyurethane prepolymer A, polyurethane prepolymer B, plasticizer, filler, carbon black, water absorbent, catalyst a and catalyst b to obtain the one-component polyurethane adhesive.

40. The preparation method according to claim 39, characterized in that The moisture content in the filler is ≤1000ppm.

41. The preparation method according to claim 39, characterized in that The moisture content in the carbon black is ≤1000ppm.

42. The preparation method according to claim 39, characterized in that The preparation method specifically comprises the following steps: first mixing polyurethane prepolymer A, polyurethane prepolymer B, plasticizer, filler, carbon black and water absorbent under vacuum conditions, and secondly adding catalyst a and catalyst b to mix to obtain the one-component polyurethane adhesive.

43. The preparation method according to claim 42, characterized in that The vacuum degree of the vacuum condition is -1000~-950 mbar.

44. Use of the one-component polyurethane adhesive according to any one of claims 1 to 38 in bonding skylight glass.

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