Single-component reactive polyurethane hot melt adhesive for aluminum honeycomb and preparation method of single-component reactive polyurethane hot melt adhesive

Abstract

The invention discloses a single-component moisture-curing reaction type polyurethane hot melt adhesive for aluminum honeycombs and a preparation method thereof, the hot melt adhesive is prepared from the following raw materials in parts by weight: 15-30 parts of isocyanate, 10-25 parts of poly (1, 6-hexanediol adipate), 5-15 parts of poly (1, 6-hexanediol dodecanoate), 5-15 parts of poly (1, 6-hexanediol isophthalate), 5-15 parts of poly (1, 6-hexanediol isophthalate), 5-15 parts of poly (1, 6-hexanediol adipate), 5-15 parts of poly (1, 6-hexanediol adipate), 5-15 parts of poly (1, 6 The invention relates to a high-temperature-resistant adhesive which is prepared from the following components in parts by weight: 2 to 10 parts of 1, 6-hexanediol-neopentyl glycol ester glycol, 5 to 15 parts of polycarbonate polyether glycol, 10 to 20 parts of polytetramethylene ether glycol, 5 to 15 parts of ethylene-vinyl acetate, 15 to 25 parts of polydodecanedioic acid-hydrogenated phthalic anhydride-methylpropanediol ester glycol, 0.01 to 0.1 part of stabilizer, 0.05 to 0.5 part of antioxidant, 0.05 to 0.5 part of catalyst and 0.1 to 5 parts of adhesion promoter. The hot melt adhesive disclosed by the invention has the characteristics of high bonding strength and excellent weather resistance, and can meet the use requirements of the current furniture market.

Description

Technical Field

[0001] The invention relates to the field of polyurethane hot melt adhesive, in particular to a single-component reactive polyurethane hot melt adhesive for aluminum honeycomb and a preparation method thereof. Background Art

[0002] Due to the excellent properties of honeycomb materials such as high wind pressure resistance, shock absorption, sound insulation, heat preservation, flame retardancy and high specific strength, aluminum honeycomb panels (abbreviated as aluminum honeycomb) are widely used in civil construction, vehicle and ship decoration, aerospace and other fields. At present, aluminum honeycombs are increasingly used in home decoration, such as beds, desks and cabinets.

[0003] Traditionally, the glues used to bond aluminum honeycombs include two-component polyurethane, two-component epoxy resin, and hot-melt adhesive film. Two-component adhesive can be cured at room temperature or at high temperature: room temperature curing for about a week or high temperature of 80°C or 100°C for a few hours can reach a certain strength; using hot-melt adhesive film, bonding is performed under pressure and heating, and strength is generated immediately after cooling, which is highly efficient. However, the room temperature curing of two-component adhesive has the problems of weak initial strength, difficulty in handling, and low efficiency; high-temperature curing will increase energy consumption, long waiting time, and low efficiency; hot-melt adhesive film has high efficiency due to high-temperature compounding, but its later strength is lower than that of two-component glue, and there is a risk of weather resistance.

[0004] Therefore, how to provide a one-component moisture-curing reactive polyurethane hot melt adhesive that combines the high initial adhesion and rapid positioning of ordinary hot melt adhesives with the high strength, water resistance, heat resistance, cold resistance, creep resistance and other characteristics of reactive polyurethane to ensure the initial strength of aluminum honeycomb and reduce curing energy consumption is a problem that needs to be solved.

[0005] In view of this, the present invention is proposed. Summary of the invention

[0006] The purpose of the present invention is to provide a single-component reactive polyurethane hot melt adhesive for aluminum honeycomb and a preparation method thereof, which has high bonding strength and excellent weather resistance, ensures the initial strength of the aluminum honeycomb and reduces the curing energy consumption, thereby solving the above-mentioned technical problems existing in the prior art.

[0007] The objective of the present invention is achieved through the following technical solutions:

[0008] A single-component moisture-curing reactive polyurethane hot melt adhesive for aluminum honeycomb is made from the following raw materials in parts by weight, the raw materials comprising:

[0009]

[0010]

[0011] Preferably, in the above hot melt adhesive, the number average molecular weight of the poly(1,6-hexanediol adipate) diol is 2000 to 4000;

[0012] The number average molecular weight of the poly (1,6-hexanediol dodecanoate) is 3000 to 4000;

[0013] The number average molecular weight of the polyisophthalic acid-1,6-hexanediol-neopentyl glycol ester diol is 500 to 3000;

[0014] The number average molecular weight of the polycarbonate polyether diol is 1500 to 2500;

[0015] The number average molecular weight of the polytetramethylene ether glycol is 1000 to 2000;

[0016] The number average molecular weight of the polydodecanedioic acid-hydrogenated phthalic anhydride-methylpropylene glycol ester diol is 3000-8000.

[0017] Preferably, in the above hot melt adhesive, the isocyanate is 4,4'-diphenylmethane diisocyanate.

[0018] Preferably, in the above hot melt adhesive, the proportion of vinyl acetate in the ethylene-vinyl acetate is 30-60%, specifically, vinyl acetate accounts for 30-60% of the entire molecular chain segment, and the rest is ethylene.

[0019] Preferably, in the above hot melt adhesive, the stabilizer is phosphoric acid.

[0020] Preferably, in the above hot melt adhesive, the antioxidant is at least one of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate, tris[2,4-di-tert-butylphenyl]phosphite, and β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate.

[0021] Preferably, in the above hot melt adhesive, the catalyst is at least one of pentamethyldiethylenetriamine, triethylenediamine, and dimorpholine diethyl ether.

[0022] Preferably, in the above hot melt adhesive, the adhesion promoter is at least one of γ-aminopropyltriethoxysilane, γ-glycidyloxypropyltrimethoxysilane and γ-methacryloxypropyltrimethoxysilane.

[0023] A method for preparing a single-component moisture-curing reactive polyurethane hot melt adhesive for aluminum honeycomb according to the present invention comprises the following steps:

[0024] Step 1: weighing various raw materials according to the formula ratio of the single-component moisture-curing reactive polyurethane hot melt adhesive for aluminum honeycomb of the present invention;

[0025] Step 2: Add poly(1,6-hexanediol adipate), poly(1,6-hexanediol dodecanoate), poly(1,6-hexanediol isophthalate-neopentyl glycol), polycarbonate polyether diol, polytetramethylene ether glycol, ethylene-vinyl acetate, poly(dodecanedioic acid-hydrogenated phthalic anhydride-methylpropylene glycol), stabilizer and antioxidant in the raw materials into a reaction kettle, control the temperature to 130-150° C., maintain the pressure at -0.06-0.095 MPa, and stir to dehydrate for 1-2 hours; then cool to 60-80° C., add isocyanate, and react at 80-100° C. for 2-3 hours;

[0026] Step 3: Add the catalyst and adhesion promoter in the raw materials into the reactor, control the temperature between 80 and 100°C, stir for 10 minutes, and maintain the vacuum degree between -0.06 and -0.095 MPa;

[0027] Step 4: Turn off stirring, degas for 10 to 20 minutes, filter, and discharge the material to obtain the single-component moisture-curing reactive polyurethane hot-melt adhesive for aluminum honeycomb of the present invention.

[0028] Compared with the prior art, the one-component reactive polyurethane hot melt adhesive for aluminum honeycomb provided by the present invention and the preparation method thereof have the following beneficial effects:

[0029] By adding poly(1,6-hexanediol adipate) and poly(1,6-hexanediol dodecanoate) and utilizing the regularity of their chain segments, rapid surface drying can be achieved and the bonding strength can be increased; by adding poly(1,6-hexanediol isophthalate)-neopentyl glycol ester, the hydrolysis resistance can be increased by utilizing the characteristic that its ester bond is protected by the steric hindrance effect of isophthalic acid, and at the same time, due to the van der Waals force between the benzene ring and the interface workpiece, the initial positioning strength of the colloid can be increased; by adding poly(dodecanedioic acid)-hydrogenated phthalic anhydride)-methylpropylene glycol ester, due to the presence of methyl groups in the main chain, the regularity of the chain segments is destroyed, the overall crystallinity is reduced, and the wettability to the substrate is increased; relative to the stacking effect of the benzene ring in phthalic anhydride, since the main chain is hydrogenated phthalic anhydride, the force between the ring structures after hydrogenation is weak, and at the same time, relative to its long chain structure, its It is more difficult to fold, has poorer crystallinity, and increases its surface wettability; at the same time, due to the strong crystallinity of dodecanedioic acid, its crystallinity and wettability are balanced in molecular structure; the polycarbonate polyether diol used is a carbon dioxide-based polycarbonate structure, and the carbonate structure on the main chain is not easy to hydrolyze, and its weather resistance is excellent. At the same time, carbon dioxide is used in the synthesis, which is in line with the country's carbon neutrality policy; by adding ethylene-vinyl acetate, using its large molecular weight and its own polarity and the interaction between the substrate, it provides a strong initial strength at the beginning of bonding; the polyester diol used has similar reaction activity, and the distribution of each polyester chain segment in the cross-linked network formed after the reaction with isocyanate is relatively uniform, and the molecular weight distribution of the synthesized hot melt adhesive is narrower, and the performance indicators of the hot melt adhesive produced are more stable, which is more conducive to customer use. In summary, the single-component reactive polyurethane hot melt adhesive used for aluminum honeycomb of the present invention has high bonding strength, can achieve high initial adhesion, rapid positioning, and excellent weather resistance such as water resistance, heat resistance, cold resistance, and creep resistance. Moreover, its construction temperature is between 120 and 160°C, which consumes less energy than ordinary hot melt adhesives with the same initial strength, which are used at 180 to 220°C. DETAILED DESCRIPTION

[0030] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in combination with the specific content of the present invention; it is obvious that the described embodiments are only part of the embodiments of the present invention, not all of the embodiments, which does not constitute a limitation of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the protection scope of the present invention.

[0031] First, the terms that may be used in this article are explained as follows:

[0032] The term “and / or” means that either or both of them can be realized at the same time. For example, X and / or Y means both “X” or “Y” and “X and Y”.

[0033] The terms "include", "comprises", "contains", "has" or other descriptions with similar semantics should be interpreted as non-exclusive inclusion. For example, including certain technical feature elements (such as raw materials, components, ingredients, carriers, dosage forms, materials, dimensions, parts, components, mechanisms, devices, steps, procedures, methods, reaction conditions, processing conditions, parameters, algorithms, signals, data, products or products, etc.) should be interpreted as including not only certain technical feature elements explicitly listed, but also other technical feature elements known in the art that are not explicitly listed.

[0034] The term "consisting of..." means excluding any technical feature elements not explicitly listed. If this term is used in a claim, it will make the claim closed, so that it does not contain technical feature elements other than the technical feature elements explicitly listed, except for the conventional impurities related to them. If this term only appears in a clause of a claim, it only limits the elements explicitly listed in the clause, and the elements recorded in other clauses are not excluded from the overall claim.

[0035] The term "parts by mass" refers to the mass ratio relationship between multiple components. For example, if it is described that component X is x parts by mass and component Y is y parts by mass, then the mass ratio of component X to component Y is x:y. 1 part by mass can represent any mass, for example, 1 part by mass can be represented as 1 kg or 3.1415926 kg. The sum of the parts by mass of all components is not necessarily 100 parts, but can be greater than 100 parts, less than 100 parts or equal to 100 parts. Unless otherwise specified, the parts, proportions and percentages described herein are all measured by mass.

[0036] When concentration, temperature, pressure, size or other parameters are expressed in the form of a numerical range, the numerical range should be understood to specifically disclose all ranges formed by the pairing of any upper limit, lower limit, and preferred value in the numerical range, regardless of whether the range is explicitly stated; for example, if a numerical range of "2 to 8" is stated, the numerical range should be interpreted as including ranges such as "2 to 7", "2 to 6", "5 to 7", "3 to 4 and 6 to 7", "3 to 5 and 7", "2 and 5 to 7", etc. Unless otherwise specified, the numerical ranges stated herein include both their end values ​​and all integers and fractions within the numerical range.

[0037] The following is a detailed description of the one-component reactive polyurethane hot melt adhesive for aluminum honeycomb provided by the present invention and its preparation method. The contents not described in detail in the embodiments of the present invention belong to the prior art known to professional and technical personnel in the field. If no specific conditions are specified in the embodiments of the present invention, the conventional conditions in the field or the conditions recommended by the manufacturer are followed. The reagents or instruments used in the embodiments of the present invention, if the manufacturer is not specified, are all conventional products that can be purchased commercially.

[0038] The embodiment of the present invention provides a one-component reactive polyurethane hot melt adhesive for aluminum honeycomb, which is a one-component reactive polyurethane hot melt adhesive with high bonding strength and excellent weather resistance. The hot melt adhesive is mainly made of the following raw materials in parts by weight: 15 to 30 parts of isocyanate, 10 to 25 parts of polyadipate-1,6-hexanediol ester diol, 5 to 15 parts of polydodecanoic acid-1,6-hexanediol ester diol, 2 to 10 parts of polyisophthalic acid-1,6-hexanediol-neopentyl glycol ester diol, 5 to 15 parts of polycarbonate polyether diol, 10 to 20 parts of polytetramethylene ether glycol, 5 to 15 parts of ethylene-vinyl acetate, 15 to 25 parts of polydodecanedioic acid-hydrogenated phthalic anhydride-methyl propylene glycol ester diol, 0.01 to 0.1 parts of stabilizer, 0.05 to 0.5 parts of antioxidant, 0.05 to 0.5 parts of catalyst, and 0.1 to 5 parts of adhesion promoter.

[0039] Preferably, in the above hot melt adhesive, the isocyanate is 4,4'-diphenylmethane diisocyanate.

[0040] Preferably, in the above-mentioned hot melt adhesive, the number average molecular weights of the poly(1,6-hexanediol adipate), poly(1,6-hexanediol dodecanoate), poly(1,6-hexanediol isophthalate-neopentyl glycol) ester diol, polycarbonate polyether diol, polytetramethylene ether glycol, and poly(dodecanedioic acid-hydrogenated phthalic anhydride-methylpropylene glycol) ester diol are 2000-4000, 3000-4000, 500-3000, 1500-2500, 1000-2000, and 3000-8000, respectively. The selected poly (1,6-hexanediol adipate) and poly (1,6-hexanediol dodecanoate) utilize the regularity of their chain segments to achieve rapid surface drying and increase the bonding strength; the selected poly (1,6-hexanediol isophthalate)-neopentyl glycol ester) utilizes the characteristic that its ester bond is protected by the steric hindrance effect of isophthalic acid to increase its hydrolysis resistance, and at the same time, due to the van der Waals force between the benzene ring and the interface component, the initial positioning strength of the colloid is increased; the selected poly (dodecanediol)-hydrogenated phthalic anhydride-methylpropylene glycol ester) has a methyl group in the main chain, which destroys the regularity of the chain segments and reduces the overall The crystallinity increases the wettability to the substrate; compared with the stacking effect of the benzene ring in phthalic anhydride, since the main chain is hydrogenated phthalic anhydride, the force between the ring structures after hydrogenation is weak, and its relatively long chain structure is more difficult to fold and has worse crystallinity, which increases its surface wettability; at the same time, due to the strong crystallinity of dodecanedioic acid, its crystallinity and wettability are balanced in the molecular structure; the selected polycarbonate polyether diol is a carbon dioxide-based polycarbonate structure, and the carbonate structure on the main chain is not easy to hydrolyze, and has excellent weather resistance. At the same time, carbon dioxide is used in the synthesis, which is in line with the country's carbon neutrality policy.

[0041] Preferably, in the above hot melt adhesive, the vinyl acetate content of the ethylene-vinyl acetate is between 30-60%; the selected ethylene-vinyl acetate provides strong initial strength at the initial stage of bonding by utilizing its large molecular weight and the interaction force between its own polarity and the substrate.

[0042] Preferably, in the above hot melt adhesive, the stabilizer is phosphoric acid.

[0043] Preferably, in the above hot melt adhesive, the antioxidant is at least one of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate, tris[2,4-di-tert-butylphenyl]phosphite, and β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate.

[0044] Preferably, in the above hot melt adhesive, the catalyst is at least one of pentamethyldiethylenetriamine, triethylenediamine, and dimorpholine diethyl ether.

[0045] Preferably, in the above hot melt adhesive, the adhesion promoter is at least one of γ-aminopropyltriethoxysilane, γ-glycidyloxypropyltrimethoxysilane and γ-methacryloxypropyltrimethoxysilane.

[0046] The embodiment of the present invention also provides a method for preparing the above-mentioned one-component moisture-curing reactive polyurethane hot melt adhesive for aluminum honeycomb, comprising the following steps:

[0047] Step 1: weigh the following raw materials in parts by weight: 15-30 parts of isocyanate, 10-25 parts of poly(1,6-hexanediol adipate), 5-15 parts of poly(1,6-hexanediol dodecanoate), 2-10 parts of poly(1,6-hexanediol isophthalate)-neopentyl glycol, 5-15 parts of polycarbonate polyether diol, 10-20 parts of polytetramethylene ether glycol, 5-15 parts of ethylene-vinyl acetate, 15-25 parts of poly(dodecanedioic acid-hydrogenated phthalic anhydride-methyl propylene glycol), 0.01-0.1 parts of stabilizer, 0.05-0.5 parts of antioxidant, 0.05-0.5 parts of catalyst, and 0.1-5 parts of adhesion promoter;

[0048] Step 2: Add polytetramethylene ether glycol, ethylene vinyl acetate, antioxidant, poly(1,6-hexanediol adipate), poly(1,6-hexanediol dodecanoate), poly(1,6-hexanediol isophthalate)-neopentyl glycol, polycarbonate polyether diol, poly(dodecanedioic acid)-hydrogenated phthalic anhydride-methylpropylene glycol) and stabilizer in the raw materials into a reaction kettle, control the temperature to 130-150° C., maintain the pressure at -0.06-0.095 MPa, and stir to dehydrate for 1-2 hours; then cool to 60-80° C., add isocyanate, and react at 80-100° C. for 2-3 hours;

[0049] Step 3: Add the catalyst and adhesion promoter in the raw materials into the reactor, control the temperature to 80-100°C, stir for 10 minutes, and maintain the vacuum degree between -0.06 and -0.095 MPa;

[0050] Step 4: Turn off the stirring, degas for 10 to 20 minutes, filter, and discharge the material to obtain the above-mentioned single-component moisture-curing reactive polyurethane hot-melt adhesive for aluminum honeycomb.

[0051] Compared with the prior art, the single-component reactive polyurethane hot melt adhesive for aluminum honeycomb of the present invention has the characteristics of high bonding strength and excellent weather resistance; the process is simple during the bonding process, which can improve work efficiency and quality control and reduce harm to the environment and physical health.

[0052] In order to more clearly demonstrate the technical solution and technical effects provided by the present invention, the one-component reactive polyurethane hot melt adhesive for aluminum honeycomb and the preparation method thereof provided by the present invention are described in detail with reference to specific embodiments.

[0053] First, the raw materials of the following embodiments are described:

[0054] MDI-100 refers to 4,4'-diphenylmethane diisocyanate;

[0055] DP-1000 refers to a polyether polyol with propylene oxide as the main chain and a number average molecular weight of 1000;

[0056] DP-200 refers to a polyether polyol with propylene oxide as the main chain and a number average molecular weight of 2000;

[0057] BR106 refers to acrylic resin with a molecular weight of about 55,000

[0058] PAA-2000 refers to poly(1,6-hexanediol adipate) with a number average molecular weight of 2000;

[0059] PAA-4000 refers to poly(1,6-hexanediol adipate) with a number average molecular weight of 4000;

[0060] PNAI-1000 refers to poly(1,6-hexanediol-neopentyl isophthalate) diol, with a number average molecular weight of 1000;

[0061] Dynacoll 7380 refers to poly(1,6-hexanediol dodecanoate) with a number average molecular weight of 3500;

[0062] PTMG-1000 is polytetramethylene ether glycol with a number average molecular weight of 100;

[0063] EVA-40 refers to ethylene vinyl acetate, with a vinyl acetate content of 40%;

[0064] PCE-2000 refers to polycarbonate polyether diol with a number average molecular weight of 2000;

[0065] Poly-A refers to polydodecanedioic acid-hydrogenated phthalic anhydride-methylpropylene glycol ester diol, with a number average molecular weight of 3000;

[0066] The stabilizer is phosphoric acid;

[0067] The antioxidant was Irganox 1010;

[0068] The catalyst is dimorpholine diethyl ether, or DMDEE;

[0069] The adhesion promoter is γ-glycidyloxypropyltrimethoxysilane, referred to as KH-560

[0070] Example 1

[0071] This embodiment provides a single-component moisture-curing reactive polyurethane hot melt adhesive for aluminum honeycomb, and the preparation method thereof comprises the following steps:

[0072] Step 1: Take the raw materials according to the following formula and amount: 1.5 kg of PTMG-1000, 1.1 kg of EVA-40, 2 kg of Poly-A, 1 kg of PCE-2000, 1.5 kg of PAA-4000, 0.8 kg of Dynacoll 7380, 0.64 kg of PNAI-1, 1.5 g of phosphoric acid, 1.5 g of Irganox 1010, 10 g of DMDEE and 50 g of KH-560;

[0073] Step 2: 1.5 kg of PTMG-1000, 1.1 kg of EVA-40, 2 kg of Poly-A, 1 kg of PCE-2000, 1.5 kg of PAA-4000, 0.8 kg of Dynacoll 7380, 0.64 kg of PNAI-1, 1.5 g of phosphoric acid and 1.5 g of Irganox 1010 in the raw materials are added to the reactor, the temperature is controlled at 130-140° C., the pressure is maintained at -0.085-0.095 MPa, and the mixture is stirred and dehydrated for 1 hour. The heating is stopped, and the temperature in the reactor is reduced to 80° C., 1.4 kg of MDI-100 is added to the reactor, and the mixture is stirred and reacted at 90-100° C. for 2 hours, and the vacuum degree is maintained at -0.085-0.095 MPa;

[0074] Step 3: Add 10g of DMDEE and 50g of KH-560 in the raw materials, stir at 90-100°C for 10min, and keep the vacuum degree at -0.085-0.095MPa;

[0075] Step 4: Turn off the stirring, degas for 10 to 20 minutes, filter, and discharge the material to obtain a single-component moisture-curing reactive polyurethane hot-melt adhesive for aluminum honeycomb.

[0076] The following comparative examples are specially designed for performance comparison of the present invention and are not prior art.

[0077] Comparative Example 1

[0078] This comparative example provides a single-component moisture-curing reactive polyurethane hot melt adhesive for aluminum honeycomb, and the preparation method thereof comprises the following steps:

[0079] Step 1: Prepare various raw materials of a single-component moisture-curing reactive polyurethane hot melt adhesive for aluminum honeycomb according to the formula;

[0080] Step 2: Add 1.4 kg of DP-1000, 1.7 kg of DP-2000, 2.2 kg of BR113, 1 kg of Poly-A, 0.8 kg of PAA-2000, 1.5 g of phosphoric acid and 1.5 g of Irganox 1010 in the raw materials into the reactor, control the temperature between 130 and 140 ° C, the vacuum degree between -0.085 and -0.095 MPa, dehydrate for 1 hour, then cool to 60-70 ° C, add 1.4 kg of MDI-100, control the temperature between 90 and 100 ° C, the vacuum degree between -0.085 and -0.095 MPa, and react for 2 hours;

[0081] Step 3: Add 10g of DMDEE and 50g of KH-560 in the raw materials, stir at 90-100°C for 10min, and keep the vacuum degree at -0.085-0.095MPa;

[0082] Step 4: Turn off the stirring, degas for 10 to 20 minutes, filter, and discharge the material to obtain the one-component moisture-curing reactive polyurethane hot melt adhesive of this comparative example.

[0083] Comparative Example 2

[0084] This comparative example provides a single-component moisture-curing reactive polyurethane hot melt adhesive for aluminum honeycomb, and the preparation method thereof comprises the following steps:

[0085] Step 1: Prepare the raw materials of the single-component moisture-curing reactive polyurethane hot melt adhesive for aluminum honeycomb according to the formula;

[0086] Step 2: 1.5 kg of PTMG-1000, 1.1 kg of EVA-40, 1.9 kg of PCE-2000, 1.9 kg of PAA-4000, 0.8 kg of Dynacoll 7380, 1.04 kg of PNAI-1, 1.5 g of phosphoric acid and 1.5 g of Irganox1010 in the raw materials are added to the reactor, the temperature is controlled at 130-140° C., the pressure is maintained at -0.085-0.095 MPa, and the mixture is stirred and dehydrated for 1 hour. The heating is stopped, and the temperature in the reactor is reduced to 80° C., 1.4 kg of MDI-100 is added to the reactor, and the mixture is stirred and reacted at 90-100° C. for 2 hours, and the vacuum degree is maintained at -0.085-0.095 MPa;

[0087] Step 3: Add 10 g of DMDEE and 50 g of KH-560, stir at 90-100 ° C for 10 min, and maintain the vacuum degree at -0.085-0.095 MPa;

[0088] Step 4: Turn off the stirring, degas for 10 to 20 minutes, filter, and discharge the material to obtain a single-component moisture-curing reactive polyurethane hot-melt adhesive for aluminum honeycomb.

[0089] Performance Testing

[0090] The following performance tests were performed on the one-component moisture-curing reactive polyurethane hot melt adhesive for aluminum honeycomb prepared in Example 1 of the present invention and the one-component moisture-curing reactive polyurethane hot melt adhesives prepared in Comparative Example 1 and Comparative Example 2 respectively:

[0091] (1) Peel force test:

[0092] The substrate is an aluminum plate of 25 mm × 100 mm × 1 mm. The one-component moisture-curing reactive polyurethane hot melt adhesive prepared in Example 1, Comparative Example 1 and Comparative Example 2 is heated to a fluid state at 130-140° C. and heated to 20-30 g / m 2 The amount of glue was scraped on the aluminum plate. Then 25mm×200mm×10mm was laminated. After lamination, 0.3MPa was used for pressing for 1min. After curing for 1h, 24h and 168h at room temperature (RT23±2℃, RH50±10%), 180° peeling force test was performed.

[0093] (2) Aging peel strength test:

[0094] The substrate is an aluminum plate of 25 mm × 100 mm × 1 mm. The one-component moisture-curing reactive polyurethane hot melt adhesive prepared in Example 1, Comparative Example 1 and Comparative Example 2 is heated to a fluid state at 130-140° C. and heated to 20-30 g / m 2Apply the glue on the aluminum plate. Then paste 25mm×200mm×10mm. After pasting, press with 0.3MPa for 1min.

[0095] Curing was carried out for 168 hours at room temperature (RT23±2℃, RH50±10%). Then the aging test was carried out under the following conditions:

[0096]

[0097] In the 180° peeling force test, the test speed is 100±10 mm / min and the test environment is room temperature (RT23±2° C., RH50±10%). After 5 groups of tests are performed in each embodiment, the average value is taken.

[0098] The test results are shown in Table 1 below.

[0099] Test items Example 1 Comparative Example 1 Comparative Example 2 180° peeling force at 1h (N / 25mm) 55 28 52 180° peeling force after 24 hours (N / 25mm) 78 58 63 180° peel force at 168h (N / 25mm) 150 88 112 Low temperature resistance 180° peeling force (N / 25mm) 200 130 155 High temperature resistant 180° peeling force (N / 25mm) 142 67 103 180° peeling force after hot and cold cycle (N / 25mm) 140 52 94

[0100] It can be clearly seen that the difference between Example 1 and Comparative Example 1 is the presence of ethylene-vinyl acetate; the difference between Example 1 and Comparative Example 2 is the presence of polydodecanedioic acid-hydrogenated phthalic anhydride-methyl propylene glycol ester diol; the common differences between Example 1, Comparative Example 2 and Comparative Example 1 are polycarbonate polyether diol and polyisophthalic acid-1,6-hexanediol-neopentyl glycol ester diol. Comparing Example 1 and Comparative Example 1, it can be clearly found that due to the presence of ethylene-vinyl acetate, its initial 1h peeling strength is very large; comparing Example 1 and Comparative Example 2, due to the high wettability of polydodecanedioic acid-hydrogenated phthalic anhydride-methyl propylene glycol ester diol, the initial peeling strength is not much different, but its strength is greater after curing for 24 hours. Comparing the weather resistance, it is found that the attenuation of Example 1 is obviously the smallest, followed by Comparative Example 2, and the most serious attenuation is Comparative Example 1. It is clearly found that the weather resistance of the system containing polycarbonate polyether diol and polyisophthalic acid-1,6-hexanediol-neopentyl glycol ester diol is better.

[0101] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed in the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims. The information disclosed in the background technology section of this article is only intended to deepen the understanding of the overall background technology of the present invention, and should not be regarded as an admission or in any form that the information constitutes prior art known to those skilled in the art.

Claims

1. A one-component moisture-curing reactive polyurethane hot melt adhesive for aluminum honeycomb, characterized in that: The invention is prepared from the following raw materials in parts by weight, the raw materials comprising:

2. The one-component moisture-curing reactive polyurethane hot melt adhesive for aluminum honeycomb according to claim 1, characterized in that: The number average molecular weight of the poly(1,6-hexanediol adipate) diol is 2000 to 4000; The number average molecular weight of the poly (1,6-hexanediol dodecanoate) is 3000 to 4000; The number average molecular weight of the polyisophthalic acid-1,6-hexanediol-neopentyl glycol ester diol is 500 to 3000; The number average molecular weight of the polycarbonate polyether diol is 1500 to 2500; The number average molecular weight of the polytetramethylene ether glycol is 1000 to 2000; The number average molecular weight of the polydodecanedioic acid-hydrogenated phthalic anhydride-methylpropylene glycol ester diol is 3000-8000.

3. The one-component moisture-curing reactive polyurethane hot melt adhesive for aluminum honeycomb according to claim 1 or 2, characterized in that: The isocyanate is 4,4'-diphenylmethane diisocyanate.

4. The one-component moisture-curing reactive polyurethane hot melt adhesive for aluminum honeycomb according to claim 1 or 2, characterized in that: The vinyl acetate in the ethylene-vinyl acetate accounts for 30-60%.

5. The one-component moisture-curing reactive polyurethane hot melt adhesive for aluminum honeycomb according to claim 1 or 2, characterized in that: The stabilizer is phosphoric acid.

6. The one-component moisture-curing reactive polyurethane hot melt adhesive for aluminum honeycomb according to claim 1 or 2, characterized in that: The antioxidant is at least one of tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] pentaerythritol ester, tris[2,4-di-tert-butylphenyl] phosphite and β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate n-octadecyl alcohol ester.

7. The one-component moisture-curing reactive polyurethane hot melt adhesive for aluminum honeycomb according to claim 1 or 2, characterized in that: The catalyst is at least one of pentamethyldiethylenetriamine, triethylenediamine and dimorpholine diethyl ether.

8. The one-component moisture-curing reactive polyurethane hot melt adhesive for aluminum honeycomb according to claim 1 or 2, characterized in that: The adhesion promoter is at least one of γ-aminopropyl triethoxysilane, γ-glycidyloxypropyl trimethoxysilane and γ-methacryloxypropyl trimethoxysilane.

9. A method for preparing the one-component moisture-curing reactive polyurethane hot melt adhesive for aluminum honeycomb according to any one of claims 1 to 8, characterized in that: The following steps are involved: Step 1: Weigh each raw material according to the formula ratio of the one-component moisture-curing reactive polyurethane hot melt adhesive for aluminum honeycomb according to any one of claims 1 to 8; Step 2: Add poly(1,6-hexanediol adipate), poly(1,6-hexanediol dodecanoate), poly(1,6-hexanediol isophthalate-neopentyl glycol), polycarbonate polyether diol, polytetramethylene ether glycol, ethylene-vinyl acetate, poly(dodecanedioic acid-hydrogenated phthalic anhydride-methylpropylene glycol), stabilizer and antioxidant in the raw materials into a reaction kettle, control the temperature to 130-150° C., maintain the pressure at -0.06-0.095 MPa, and stir to dehydrate for 1-2 hours; then cool to 60-80° C., add isocyanate, and react at 80-100° C. for 2-3 hours; Step 3: Add the catalyst and adhesion promoter in the raw materials into the reactor, control the temperature between 80 and 100°C, stir for 10 minutes, and maintain the vacuum degree between -0.06 and -0.095 MPa; Step 4: Turn off stirring, degas for 10 to 20 minutes, filter, and discharge the material to obtain the single-component moisture-curing reactive polyurethane hot-melt adhesive for aluminum honeycomb according to any one of claims 1 to 8.

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