Self-crosslinking high-temperature-resistant chloroprene rubber adhesive as well as preparation method and application thereof

Abstract

The invention relates to a self-crosslinking high-temperature-resistant chloroprene rubber adhesive as well as a preparation method and application thereof. The invention relates to a self-crosslinking high-temperature-resistant chloroprene rubber adhesive. Comprising 2 to 4 parts by weight of methacrylic acid, 10 to 13 parts by weight of methyl methacrylate, 30 to 35 parts by weight of butanone, 0.4 to 0.6 part by weight of active magnesium oxide, 3 to 6 parts by weight of tert-butyl phenolic resin, 8 to 12 parts by weight of sec-butyl acetate, 12 to 15 parts by weight of chloroprene rubber, 0.1 to 0.2 part by weight of benzoyl peroxide and 24 to 28 parts by weight of toluene. The chloroprene rubber adhesive with the heat-resistant temperature of 100 DEG C or above is formed. The resin may improve characteristic adhesion and self-adhesion while increasing heat resistant cohesive strength.

Description

Technical Field

[0001] The invention relates to an adhesive, in particular to a self-crosslinking high-temperature resistant chloroprene rubber adhesive and a preparation method and application thereof. Background Art

[0002] Chloroprene adhesive is an important variety with the largest output and the most applications among rubber adhesives. Since chloroprene rubber has a relatively regular structure and contains chlorine atoms with a large polarity, it has high crystallinity, which makes it have good bonding performance and large cohesive strength at room temperature. Therefore, chloroprene adhesive is generally a room temperature curing contact adhesive. After being applied to the surface and properly dried and closed in contact, the molecules can be neatly arranged and crystallized instantly, and have a large initial bonding force.

[0003] At present, solvent-based chloroprene rubber adhesive is still the most widely used and dominant type of solvent-based adhesive. Solvent-based chloroprene rubber adhesive is a thermoplastic adhesive, so it has poor heat resistance. Generally, at 70-80℃, solvent-based chloroprene rubber adhesive begins to debond due to heat.

[0004] The car roof needs to be bonded to metal, ABS plastic, leather, artificial leather and other materials. If ordinary neoprene adhesive is used, the car roof is very easy to debond due to high temperature in summer.

[0005] Therefore, a high temperature resistant solvent-based chloroprene adhesive is needed. Summary of the invention

[0006] The purpose of the present invention is to provide a self-crosslinking high temperature resistant chloroprene rubber adhesive. The present invention solves the problem that the solvent-based chloroprene rubber adhesive has poor heat resistance and cannot be used as an automobile ceiling adhesive.

[0007] The technical solution adopted by the present invention is as follows:

[0008] A self-crosslinking high temperature resistant chloroprene rubber adhesive comprises the following components in parts by weight:

[0009] 2-4 parts by weight of methacrylic acid, 10-13 parts by weight of methyl methacrylate, 30-35 parts by weight of butanone, 0.4-0.6 parts by weight of active magnesium oxide, 3-6 parts by weight of tert-butyl phenolic resin, 8-12 parts by weight of sec-butyl acetate, 12-15 parts by weight of SN240T type chloroprene rubber, 0.1-0.2 parts by weight of benzoyl peroxide, 24-28 parts by weight of toluene, and 0.2-0.3 parts by weight of antioxidant BHT.

[0010] The preparation method of the self-crosslinking high temperature resistant chloroprene rubber adhesive of the present invention comprises the following steps:

[0011] 1) Chelating reaction of tert-butylphenol-formaldehyde resin: first add a small amount of toluene, tert-butylphenol-formaldehyde resin and active magnesium oxide into a stirred tank and stir at high speed (800-1200 rpm) for 1-2 hours to obtain a tert-butylphenol-formaldehyde resin chelating liquid;

[0012] 2) Film dissolution: Add remaining toluene, butanone, sec-butyl acetate and chloroprene rubber, and stir at high speed for 5-6 hours (800-1200 rpm) until the chloroprene rubber is completely dissolved;

[0013] 3) Graft copolymerization: Heat to 80°C, add a mixture of methacrylic acid and methyl methacrylate at 80-90°C, and simultaneously add a dispersion of benzoyl peroxide; add and stir for 2-4 hours, and when the glue in the reactor climbs up the rod, cool it down immediately to lower the temperature;

[0014] 4) Termination of reaction and cooling: Add antioxidant, and when the temperature drops below 40°C, add tert-butylphenol-formaldehyde resin chelating liquid.

[0015] The present invention forms a carboxyl-grafted chloroprene rubber copolymer by grafting and copolymerizing chloroprene rubber with methacrylic acid and methyl methacrylate. The carboxyl-grafted chloroprene rubber copolymer can undergo a self-crosslinking reaction with the resin, chelating agent and active magnesium oxide in the glue solution to form a chloroprene rubber adhesive with a heat-resistant temperature of more than 100°C. The resin can improve the characteristic adhesion and self-adhesion, while increasing the heat-resistant cohesive strength. In the present invention, tert-butylphenolic resin and active magnesium oxide are pre-reacted to form a tert-butylphenolic resin-magnesium oxide chelate, which fully improves the heat resistance of the chloroprene rubber adhesive and the stability of the glue solution. At the same time, excess magnesium oxide enters the glue solution and undergoes a self-crosslinking reaction with the carboxyl-grafted chloroprene rubber copolymer at a certain temperature to form a high-temperature resistant chloroprene rubber adhesive. DETAILED DESCRIPTION

[0016] In order to make the technical personnel in the field understand the present invention more clearly and intuitively, the present invention will be further described below. The experimental methods without specific conditions in the following examples are selected according to conventional methods and conditions, or according to the product instructions.

[0017] Example 1

[0018] The composition of the self-crosslinking high temperature resistant chloroprene rubber adhesive of this embodiment is shown in Table 1.

[0019] Table 1

[0020]

[0021]

[0022] The preparation method of the self-crosslinking high temperature resistant chloroprene rubber adhesive of this embodiment comprises the following steps:

[0023] 1) Chelating reaction of tert-butylphenol-formaldehyde resin: 10 parts by weight of toluene, 6 parts by weight of tert-butylphenol-formaldehyde resin and 0.6 parts by weight of active magnesium oxide were first added into a stirred tank and stirred at high speed (800 rpm) for 2 hours to obtain a tert-butylphenol-formaldehyde resin chelating liquid;

[0024] 2) Film dissolution: add the remaining 14 parts by weight of toluene, 35 parts by weight of butanone, 8 parts by weight of sec-butyl acetate and 15 parts by weight of SN240T chloroprene rubber, and stir at high speed for 6 hours (800 rpm) until the chloroprene rubber is completely dissolved;

[0025] 3) Graft copolymerization: Raise the temperature to 80°C, add a mixture of methacrylic acid and methyl methacrylate at 80°C-90°C, and simultaneously add benzoyl peroxide; add and stir for 2-4 hours, and when the glue in the reactor climbs up the rod, cool it down immediately to lower the temperature;

[0026] 4) Termination of reaction and cooling: adding 0.3 parts by weight of antioxidant BHT, and adding tert-butylphenolic resin chelating liquid when the temperature drops below 40° C. to obtain a self-crosslinking high temperature resistant chloroprene rubber adhesive.

[0027] Performance Test:

[0028] The self-crosslinking high temperature resistant chloroprene rubber adhesive has fast drying speed, high strength and good heat resistance. It can be bonded after drying at room temperature for 15 minutes and drying at 50℃ for 3 minutes.

[0029] Heat resistance test (PVC leather-PVC leather): 100°C×10 minutes×0.5kg (bonding area 2.5cm×8cm), peeling distance 0.1cm.

[0030] Peel strength: 2.87KN / m (PVC leather-PVC leather).

[0031] Example 2

[0032] The composition of the self-crosslinking high temperature resistant chloroprene rubber adhesive of this embodiment is shown in Table 2.

[0033] Table 2

[0034]

[0035]

[0036] The preparation method of the self-crosslinking high temperature resistant chloroprene rubber adhesive of this embodiment comprises the following steps:

[0037] 1) Chelating reaction of tert-butylphenol-formaldehyde resin: 10 parts by weight of toluene, 5 parts by weight of tert-butylphenol-formaldehyde resin and 0.5 parts by weight of active magnesium oxide were first added into a stirred tank and stirred at high speed (1000 rpm) for 1.5 hours to obtain a tert-butylphenol-formaldehyde resin chelating liquid;

[0038] 2) Film dissolution: add the remaining 18 parts by weight of toluene, 30 parts by weight of butanone, 10 parts by weight of sec-butyl acetate and 12 parts by weight of SN240T chloroprene rubber, and stir at high speed for 5.5 hours (1000 rpm) until the chloroprene rubber is completely dissolved;

[0039] 3) Graft copolymerization: Raise the temperature to 80°C, add a mixture of methacrylic acid and methyl methacrylate at 80°C-90°C, and simultaneously add benzoyl peroxide; add and stir for 2-4 hours, and when the glue in the reactor climbs up the rod, cool it down immediately to lower the temperature;

[0040] 4) Termination of reaction and cooling: adding 0.3 parts by weight of antioxidant BHT, and adding tert-butylphenolic resin chelating liquid when the temperature drops below 40° C. to obtain a self-crosslinking high temperature resistant chloroprene rubber adhesive.

[0041] Performance Test:

[0042] The drying speed of the self-crosslinking high temperature resistant chloroprene rubber adhesive prepared is slightly slower than that of Example 1, and the heat resistance is slightly worse. Dry at room temperature for 15 minutes, and dry at 50°C for 3 minutes for bonding.

[0043] Heat resistance test (PVC leather-PVC leather): 100°C×10 minutes×0.5kg (bonding area 2.5cm×8cm), peeling distance 0.3cm.

[0044] Peel strength: 2.48KN / m (PVC leather-PVC leather).

[0045] Example 3

[0046] The composition of the self-crosslinking high temperature resistant chloroprene rubber adhesive of this embodiment is shown in Table 3.

[0047] Table 3

[0048]

[0049]

[0050] The preparation method of the self-crosslinking high temperature resistant chloroprene rubber adhesive of this embodiment comprises the following steps:

[0051] 1) Chelating reaction of tert-butylphenol-formaldehyde resin: 10 parts by weight of toluene, 3 parts by weight of tert-butylphenol-formaldehyde resin and 0.4 parts by weight of active magnesium oxide were first added into a stirred tank and stirred at high speed (1200 rpm) for 1 hour to obtain a tert-butylphenol-formaldehyde resin chelating liquid;

[0052] 2) Film dissolution: Add the remaining 16 parts by weight of toluene, 33 parts by weight of butanone, 12 parts by weight of sec-butyl acetate and 13 parts by weight of SN240T chloroprene rubber, and stir at high speed for 5 hours (1200 rpm) until the chloroprene rubber is completely dissolved;

[0053] 3) Graft copolymerization: Heat to 80°C, add a mixture of methacrylic acid and methyl methacrylate at 80-90°C, and simultaneously add a dispersion of benzoyl peroxide; add and stir for 2-4 hours, and when the glue in the reactor climbs up the rod, cool it down immediately to lower the temperature;

[0054] 4) Termination of reaction and cooling: Add 0.2 parts by weight of antioxidant BHT, and when the temperature drops to below 40° C., add tert-butylphenol-formaldehyde resin chelating liquid to obtain the product.

[0055] Performance Test:

[0056] The self-crosslinking high temperature resistant chloroprene rubber adhesive has fast drying speed, high strength, and slightly poor heat resistance. Dry at room temperature for 15 minutes and dry at 50℃ for 3 minutes for bonding.

[0057] Heat resistance test (PVC leather-PVC leather): 100°C×10 minutes×0.5kg (bonding area 2.5cm×8cm), peeling distance 0.3cm.

[0058] Peel strength: 2.76KN / m (PVC leather-PVC leather).

[0059] Comparative Example 1

[0060] The composition of the self-crosslinking high temperature resistant chloroprene rubber adhesive of this comparative example is shown in Table 4.

[0061] Table 4

[0062] Components Dosage (parts by weight) Methacrylic acid 4 Methyl Methacrylate 13 Butanone 35 Activated Magnesium Oxide 0.3 Tert-butylphenol-formaldehyde resin 6 sec-Butyl acetate 8 SN240T Neoprene 15 Benzoyl peroxide (50% dispersion) 0.2 Toluene 24 Antioxidant BHT 0.3

[0063] The preparation method is the same as that in Example 1.

[0064] Performance Test:

[0065] The self-crosslinking high temperature resistant chloroprene rubber adhesive has a slower drying speed than that of Example 1, has high strength, and poor heat resistance. It can be bonded after drying at room temperature for 18 minutes and drying at 50°C for 5 minutes.

[0066] Heat resistance test (PVC leather-PVC leather): 100°C×10 minutes×0.5kg (bonding area 2.5cm×8cm), peeling distance 1.5cm.

[0067] Peel strength: 1.68KN / m (PVC leather-PVC leather).

[0068] From the test results, at a high temperature of 100°C and a peel strength of 1.68KN / m, a distance of 1.5cm can be peeled off in 10 minutes. This shows that the reduction in the amount of active magnesium oxide has a great impact on the heat resistance. The reason is that the amount of active magnesium oxide is relatively small. Except for the pre-reaction with tert-butyl phenolic resin, not enough active magnesium oxide enters the glue solution, which affects the self-crosslinking reaction between active magnesium oxide and carboxyl-grafted chloroprene rubber copolymer, thereby affecting the heat resistance.

[0069] Comparative Example 2

[0070] The composition of the self-crosslinking high temperature resistant chloroprene rubber adhesive of this comparative example is shown in Table 5.

[0071] Table 5

[0072]

[0073]

[0074] The preparation method is the same as that in Example 2.

[0075] Performance Test:

[0076] The self-crosslinking high temperature resistant chloroprene rubber adhesive has a fast drying speed, slightly lower strength and poor heat resistance. It can be bonded after drying at room temperature for 15 minutes and drying at 50℃ for 3 minutes.

[0077] Heat resistance test (PVC leather-PVC leather): 100°C×10 minutes×0.5kg (bonding area 2.5cm×8cm), peeling distance 2.1cm.

[0078] Peel strength: 1.89KN / m (PVC leather-PVC leather).

[0079] From the test results, at a high temperature of 100°C and a peel strength of 1.89KN / m, a distance of 2.1cm can be peeled off in 10 minutes. The results show that excessive use of active magnesium oxide has a great impact on heat resistance. The reason is that the amount of active magnesium oxide is relatively small. In addition to the pre-reaction with tert-butyl phenolic resin, the excess active magnesium oxide enters the adhesive solution and reacts with the self-crosslinking reaction of the carboxyl-grafted chloroprene rubber copolymer. Excessive active magnesium oxide causes excessive self-crosslinking reaction in the adhesive, thereby affecting the heat resistance of the adhesive.

[0080] Through analysis, it can be known that the heat resistance of the chloroprene rubber adhesive of the present invention has an important relationship with the amount of active magnesium oxide added. Too little or too much can affect the final heat resistance of the adhesive.

[0081] The above description of the embodiments is to facilitate the understanding and application of the present invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the embodiments herein, and improvements and modifications made to the present invention by those skilled in the art based on the disclosure of the present invention should be within the scope of protection of the present invention.

Claims

1. A self-crosslinking high temperature resistant chloroprene rubber adhesive, characterized in that: The composition comprises the following components in parts by weight: 2-4 parts by weight of methacrylic acid, 10-13 parts by weight of methyl methacrylate, 30-35 parts by weight of butanone, 0.4-0.6 parts by weight of active magnesium oxide, 3-6 parts by weight of tert-butylphenol-formaldehyde resin, 8-12 parts by weight of sec-butyl acetate, 12-15 parts by weight of chloroprene rubber, 0.1-0.2 parts by weight of benzoyl peroxide, and 24-28 parts by weight of toluene; Active magnesium oxide and tert-butylphenol-formaldehyde resin form tert-butylphenol-formaldehyde resin-magnesium oxide chelate; Active magnesium oxide also undergoes self-crosslinking reaction with the carboxyl-grafted chloroprene rubber copolymer formed by grafting chloroprene rubber with methacrylic acid and methyl methacrylate.

2. A self-crosslinking high temperature resistant chloroprene rubber adhesive as claimed in claim 1, characterized in that: It also includes 0.2-0.3 parts by weight of an antioxidant.

3. A self-crosslinking high temperature resistant chloroprene rubber adhesive, characterized in that: The composition comprises the following components in parts by weight: 4 parts by weight of methacrylic acid, 13 parts by weight of methyl methacrylate, 35 parts by weight of butanone, 0.6 parts by weight of active magnesium oxide, 6 parts by weight of tert-butylphenol-formaldehyde resin, 8 parts by weight of sec-butyl acetate, 15 parts by weight of chloroprene rubber, 0.2 parts by weight of benzoyl peroxide dispersion, 24 parts by weight of toluene, and 0.3 parts by weight of antioxidant.

4. The method for preparing the self-crosslinking high temperature resistant chloroprene rubber adhesive according to claim 2 or 3, characterized in that: The steps include: 1) Chelating reaction of tert-butylphenol-formaldehyde resin: firstly add a small amount of toluene, tert-butylphenol-formaldehyde resin and active magnesium oxide into a stirring kettle and stir at high speed to obtain a tert-butylphenol-formaldehyde resin chelating liquid; 2) Film dissolution: Add remaining toluene, butanone, sec-butyl acetate and chloroprene rubber, and stir at high speed until the chloroprene rubber is completely dissolved; 3) Graft copolymerization: Heat to 80°C, add a mixture of methacrylic acid and methyl methacrylate at 80-90°C, and simultaneously add a dispersion of benzoyl peroxide; add and stir for 2-4 hours, and when the glue in the reactor climbs up the rod, cool it down immediately to lower the temperature; 4) Termination of reaction and cooling: Add antioxidant, and when the temperature drops below 40°C, add tert-butylphenol-formaldehyde resin chelating liquid.

5. The preparation method according to claim 4, characterized in that: The stirring condition in step 1) is 800-1200 rpm, and the stirring is for 1-2 hours.

6. The preparation method according to claim 4, characterized in that: The stirring condition in step 2) is 800-1200 rpm, and the stirring is performed for 5-6 hours.

7. Use of the self-crosslinking high temperature resistant chloroprene rubber adhesive as claimed in claim 2 or 3 in bonding metal, ABS plastic, leather and artificial leather on automobile roofs.

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