Two-component polyurethane adhesive as well as preparation method and application thereof

Abstract

The invention discloses a two-component polyurethane adhesive as well as a preparation method and application thereof. The two-component polyurethane adhesive is prepared from the following raw materials in volume ratio: the ratio of a component A to a component B is 1: (0.4-0.6), the component A comprises the following components in parts by weight: 15-40 parts of hydroxyl-terminated polybutadiene, 2-20 parts of castor oil and / or modified castor oil, 5-20 parts of bisphenol A polyether polyol, 30-55 parts of filler, 0-1 part of a catalyst, 0.01-1 part of a silane coupling agent and 0-2 parts of a chain extender; the component B is prepared from the following components in parts by weight: 20 to 60 parts of isocyanate-terminated polyurethane prepolymer, 15 to 40 parts of isocyanate, 10 to 50 parts of filler and 0.01 to 1 part of water removal agent. The two-component polyurethane adhesive has the characteristics of high bonding strength, good high-temperature resistance, good aging resistance and the like, and is particularly suitable for bonding metals, low-surface-energy plastics subjected to surface treatment, composite materials and foam.

Description

Technical Field

[0001] The invention relates to a two-component polyurethane adhesive and a preparation method and application thereof, belonging to the technical field of polyurethane adhesives. Background Art

[0002] With the continuous progress of society and the steady development of the national economy, the polyurethane adhesive industry has also entered a period of rapid growth and continued to grow rapidly. The application areas of polyurethane adhesives are constantly expanding, from traditional application areas such as packaging, leather, textiles, footwear, furniture, to emerging application areas such as home appliances, building materials, transportation, new energy, safety protection, etc., with broad market development prospects.

[0003] In the process of rapid development of new energy vehicles, the anxiety of driving range has always been a topic that cannot be avoided, so the thermal insulation effect of the battery is very important, and the adhesive used to bond the foam and aluminum alloy of the battery pack is particularly important. However, the bonding of foam and metal, low surface energy plastics, and composite materials has always been a difficult problem. The current adhesives can have a good bonding effect on a single substrate, but cannot achieve mutual bonding, and most of them contain solvents and / or plasticizers, and have poor high temperature resistance. Therefore, it is urgent to develop an adhesive that has a good bonding effect on foam and metal, low surface energy plastics, and composite materials, especially suitable for the bonding of buffer foam to metal parts. Summary of the invention

[0004] Purpose of the invention: The first purpose of the present invention is to provide a two-component polyurethane adhesive. The second purpose of the present invention is to provide a method for preparing the two-component polyurethane adhesive. The third purpose of the present invention is to provide an application of the two-component polyurethane adhesive in the bonding of buffer foam of metal parts.

[0005] Technical solution: The present invention discloses a two-component polyurethane adhesive, which is made of the following raw materials in a volume ratio: component A: component B is 1:0.4-0.6, wherein component A comprises the following components in parts by weight: 15-40 parts of terminal hydroxyl polybutadiene, 2-20 parts of castor oil and / or modified castor oil, 5-20 parts of bisphenol A polyether polyol, 30-55 parts of filler, 0-1 part of catalyst, 0.01-1 part of silane coupling agent, and 0-2 parts of chain extender; component B comprises the following components in parts by weight: 20-60 parts of isocyanate-terminated polyurethane prepolymer, 15-40 parts of isocyanate, 10-50 parts of filler, and 0.01-1 part of dewatering agent.

[0006] Furthermore, the hydroxy-terminated polybutadiene is one or more independently selected from the group having a molecular weight Mn of 1000-10000 and a hydroxyl content of 0.2-2.0 mmol / g.

[0007] Furthermore, the castor oil is first-grade castor oil.

[0008] Furthermore, the modified castor oil is selected from one or more of A4100, A4110 or A4120.

[0009] Furthermore, the bisphenol A polyether polyol is selected from BPA3PO.

[0010] Furthermore, the chain extender is one or more of 1,4-butanediol, propylene glycol or dipropylene glycol.

[0011] Furthermore, the filler is one or more of fumed silica, silicon powder, diatomaceous earth, titanium dioxide, heavy calcium carbonate, nano calcium carbonate, aluminum hydroxide, modified aluminum hydroxide, molecular sieve or hollow glass microspheres.

[0012] Furthermore, the catalyst is one or more of dibutyltin dilaurate, bismuth neodecanoate or triethylenediamine.

[0013] Furthermore, the silane coupling agent is one or more of KH-560, KH-570 or CG-1146.

[0014] Further, the NCO content of the isocyanate terminated polyurethane prepolymer is 12.5-13.3%.

[0015] Furthermore, the isocyanate is selected from one or more of MDI LL, MDI-50, M20S or PM-200.

[0016] Furthermore, the dehydrating agent is one or more of oxazolidine ALT-201 or Additive TI.

[0017] Furthermore, the preparation method of the isocyanate-terminated polyurethane prepolymer comprises the following steps:

[0018] The terminal hydroxyl polybutadiene is dehydrated to make the water content less than 500 ppm, and then isocyanate is added and mixed evenly, and the temperature is controlled between 70 and 90° C. to react for more than 2 hours.

[0019] A method for preparing the two-component polyurethane adhesive of the present invention comprises the following steps:

[0020] (1) mixing and stirring terminal hydroxyl polybutadiene, castor oil and / or modified castor oil, bisphenol A polyether polyol, filler, catalyst, silane coupling agent and chain extender to obtain material A;

[0021] (2) mixing and stirring the isocyanate-terminated polyurethane prepolymer, isocyanate, filler, and dewatering agent to obtain material B;

[0022] (3) Mix material A and material B at high speed and stir until evenly mixed.

[0023] Application of the two-component polyurethane adhesive in the bonding of buffer foams of metal parts.

[0024] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages:

[0025] The invention provides a two-component polyurethane adhesive with good bonding performance and aging resistance. It has good bonding effect on plastics and composite materials, especially foam and metal and low surface energy plastics and composite materials. The preparation method is simple and easy, and it does not contain solvents and plasticizers. It can still maintain good bonding performance at high temperatures and is environmentally friendly and durable. DETAILED DESCRIPTION

[0026] The technical solution of the present invention is further described below in conjunction with embodiments.

[0027] The method for preparing a two-component polyurethane adhesive of the present invention comprises the following steps:

[0028] (1) preparing component A: at room temperature, adding 15-40 parts by weight of hydroxy-terminated polybutadiene, 2-20 parts by weight of castor oil and / or modified castor oil, 5-20 parts by weight of bisphenol A polyether polyol, 30-55 parts by weight of filler, 0-1 part by weight of catalyst, 0.01-1 part by weight of silane coupling agent, and 0-2 parts by weight of chain extender into container A, and stirring to obtain component A;

[0029] (2) preparing component B: at room temperature, add 20-60 parts of isocyanate-terminated polyurethane prepolymer, 15-40 parts of isocyanate, 10-50 parts of filler, and 0.01-1 part of dewatering agent in container B by weight, stir evenly, and then discharge to obtain component B;

[0030] The isocyanate-terminated polyurethane prepolymer is obtained by reacting terminal hydroxyl polybutadiene with isocyanate, specifically, 50 parts by weight of terminal hydroxyl polybutadiene are dehydrated to make the water content less than 500 ppm, and then 50 parts of isocyanate are added and mixed evenly, and the temperature is controlled at 80° C. for 2 hours to obtain a prepolymer having an NCO content of 12.88%;

[0031] (3) Component A and component B are mixed evenly at a volume ratio of 1:0.4-0.6 to obtain a two-component polyurethane adhesive. The specific raw materials are shown in Table 1.

[0032] Table 1 Raw materials and sources

[0033]

[0034] Embodiments 1 to 5

[0035] Prepare component A and component B according to Table 2, and evenly mix component A and component B at a volume ratio of 1:0.4-0.6 to obtain a two-component polyurethane adhesive.

[0036] Comparative Examples 1-3

[0037] Prepare component A and component B according to Table 2. The difference from Examples 1-5 is that the amount of raw materials is controlled differently. Component A and component B are evenly mixed at a volume ratio of 1:0.4-0.6 to obtain a two-component polyurethane adhesive.

[0038] Table 2 Components and raw materials of Examples 1 to 5 and Comparative Examples 1 to 3

[0039]

[0040]

[0041] The two-component polyurethane adhesives prepared in Examples 1-5 and Comparative Examples 1-3 were subjected to tensile property tests according to GB-T1040.1-2006 "Test Methods for Tensile Properties of Plastics" and tensile shear strength tests according to GB-T 7124-1986 "Test Methods for Tensile Shear Strength of Adhesives (Metal to Metal)". The results are shown in Table 3.

[0042] Table 3 Performance data of two-component polyurethane adhesives prepared in Examples 1-3 and Comparative Examples 1-3

[0043]

[0044] As can be seen from Table 3, the adhesive prepared by the method of the present invention has good bonding performance at room temperature, and shows significantly better performance than the comparative example in high temperature and aging, and can still maintain a shear strength of more than 5MPa at 60°C. When actually used for foam and aluminum bonding, a manual destructive test was performed on the foam. After the adhesive prepared by the method of the present invention was destroyed, no metal was exposed, and basically all the foam was destroyed. In the comparative example, only two of the terminal hydroxyl polybutadiene, modified castor oil, and bisphenol A polyether were used, and the above effect could not be achieved. It can be seen that the three can achieve good bonding performance at both room temperature and high temperature and a strong bond with foam and metal under the synergistic effect of a certain proportion.

Claims

1. A two-component polyurethane adhesive, characterized in that: The two-component polyurethane adhesive is made of the following raw materials in a volume ratio: component A: component B is 1:0.4-0.6, wherein component A comprises the following components in parts by weight: 15-40 parts of terminal hydroxyl polybutadiene, 2-20 parts of castor oil and / or modified castor oil, 5-20 parts of bisphenol A polyether polyol, 30-55 parts of filler, 0-1 part of catalyst, 0.01-1 part of silane coupling agent, and 0-2 parts of chain extender; component B comprises the following components in parts by weight: 20-60 parts of isocyanate-terminated polyurethane prepolymer, 15-40 parts of isocyanate, 10-50 parts of filler, and 0.01-1 part of dewatering agent.

2. The two-component polyurethane adhesive according to claim 1, characterized in that: The hydroxy-terminated polybutadiene is one or more independently selected from the group consisting of polybutadienes having a molecular weight Mn of 1000-10000 and a hydroxyl content of 0.2-2.0 mmol / g.

3. The two-component polyurethane adhesive according to claim 3, characterized in that: The castor oil is first-grade castor oil, and the modified castor oil is selected from one or more of A4100, A4110 or A4120.

4. The two-component polyurethane adhesive according to claim 1, characterized in that: The bisphenol A polyether polyol is selected from BPA3PO, and the chain extender is one or more of 1,4-butanediol, propylene glycol or dipropylene glycol.

5. The two-component polyurethane adhesive according to claim 1, characterized in that: The filler is one or more of fumed silica, silicon powder, diatomaceous earth, titanium dioxide, heavy calcium carbonate, nano calcium carbonate, aluminum hydroxide, modified aluminum hydroxide, molecular sieve or hollow glass microspheres.

6. The two-component polyurethane adhesive according to claim 1, characterized in that: The catalyst is one or more of dibutyltin dilaurate, bismuth neodecanoate or triethylenediamine; the silane coupling agent is one or more of KH-560, KH-570 or CG-1146.

7. The two-component polyurethane adhesive according to claim 1, characterized in that: The NCO content of the isocyanate-terminated polyurethane prepolymer is 12.5-13.3%; the isocyanate is selected from one or more of MDI LL, MDI-50, M20S or PM-200; and the dehydrating agent is one or more of oxazolidine ALT-201 or Additive TI.

8. The two-component polyurethane adhesive according to claim 1, characterized in that: The method for preparing an isocyanate-terminated polyurethane prepolymer comprises the following steps: The terminal hydroxyl polybutadiene is dehydrated to make the water content less than 500 ppm, and then isocyanate is added and mixed evenly, and the temperature is controlled between 70 and 90° C. to react for more than 2 hours.

9. A method for preparing the two-component polyurethane adhesive according to any one of claims 1 to 8, characterized in that: The following steps are involved: (1) mixing and stirring terminal hydroxyl polybutadiene, castor oil and / or modified castor oil, bisphenol A polyether polyol, filler, catalyst, silane coupling agent and chain extender to obtain material A; (2) mixing and stirring the isocyanate-terminated polyurethane prepolymer, isocyanate, filler, and dewatering agent to obtain material B; (3) Mix material A and material B at high speed and stir until evenly mixed.

10. Use of the two-component polyurethane adhesive according to any one of claims 1 to 8 in bonding buffer foam of metal parts.

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