Pressure-sensitive adhesive, preparation method thereof and pressure-sensitive adhesive tape

Abstract

The invention discloses a pressure-sensitive adhesive, a preparation method thereof and a pressure-sensitive adhesive tape. The pressure-sensitive adhesive comprises the following raw materials: 40-60 parts of 2-ethylhexyl acrylate; 25 to 50 parts of butyl acrylate; 10 to 20 parts of glycidyl methacrylate; 1-10 parts of acrylic acid; 1 to 10 parts of 2-hydroxyethyl methacrylate; 0.1 to 1.0 part of dodecyl mercaptan; the organic silicon polyether copolymer is selected from the group consisting of OFX-3667, BY16-201, OFX-5043 and OFX-0400, and the organic silicon polyether copolymer is selected from the group consisting of OFX-3667, BY16-201, OFX-5043 and And 0.1 to 5.0 parts of an initiator. The pressure-sensitive adhesive disclosed by the invention has the characteristics of strong viscosity, good waterproofness, easiness in processing and the like, and can be widely applied to manufacturing of various products such as adhesive tapes, labels and the like.

Description

Technical Field

[0001] The invention relates to the field of adhesives, and in particular to a pressure-sensitive adhesive and a preparation method thereof, and a pressure-sensitive adhesive tape. Background Art

[0002] Pressure sensitive adhesive (PSA) is an adhesive that only needs a small amount of pressure to achieve good bonding performance, and after peeling, no residual colloid will contaminate the bonded material. This adhesive can be bonded at room temperature without solvent evaporation or chemical reaction, which makes the application of PSA particularly easy and safe.

[0003] According to the monomer material, pressure sensitive adhesives are mainly divided into: polyurethane pressure sensitive adhesives, acrylate pressure sensitive adhesives, silicone pressure sensitive adhesives and epoxy resin pressure sensitive adhesives. Among them, acrylate pressure sensitive adhesives are the most important and widely used type of pressure sensitive adhesives, with the advantages of many synthetic monomer types, high transparency, and good aging resistance.

[0004] However, due to the polar groups contained in traditional acrylic polymer pressure-sensitive adhesives, their water vapor transmission rate (WVTR) is relatively high, which largely limits their wide application in the field of power and electronic equipment.

[0005] In addition, the shrinkage and cracking problems that are prone to occur during use of pressure-sensitive adhesives also seriously restrict the firmness and durability of their adhesion, making it difficult to meet the needs of electronic equipment for stable and long-lasting adhesion.

[0006] Therefore, how to provide a pressure-sensitive adhesive with low water vapor permeability resistance is a technical problem to be solved urgently in this field. Summary of the invention

[0007] To achieve the above-mentioned purpose, the present invention provides a pressure-sensitive adhesive and a preparation method thereof, and a pressure-sensitive adhesive tape.

[0008] The present invention provides a pressure-sensitive adhesive, the raw materials of which include:

[0009] 40-60 parts of isooctyl acrylate;

[0010] 25-50 parts of butyl acrylate;

[0011] 10-20 parts of glycidyl methacrylate;

[0012] 1-10 parts of acrylic acid;

[0013] 1-10 parts of 2-hydroxyethyl methacrylate;

[0014] 0.1-1.0 parts of dodecyl mercaptan;

[0015] 1-10 parts of an organosilicon polyether copolymer, wherein the organosilicon polyether copolymer is selected from OFX-3667, BY16-201, OFX-5043, and OFX-0400;

[0016] 0.1-5.0 parts of initiator.

[0017] In a preferred embodiment of the present invention, the amount of isooctyl acrylate is 50 parts.

[0018] In a preferred embodiment of the present invention, the amount of butyl acrylate is 25-50 parts, such as 25 parts or 50 parts.

[0019] In a preferred embodiment of the present invention, the mass ratio of the isooctyl acrylate to the butyl acrylate is (1-2):1.

[0020] In a preferred embodiment of the present invention, the amount of glycidyl methacrylate is 10-15 parts, such as 12.5 parts or 15 parts.

[0021] In a preferred embodiment of the present invention, the amount of acrylic acid is 1-5 parts, such as 3.5 parts or 5 parts.

[0022] In a preferred embodiment of the present invention, the amount of 2-hydroxyethyl methacrylate is 1-5 parts, for example 3.5 parts.

[0023] In a preferred embodiment of the present invention, the amount of dodecyl mercaptan is 0.1-0.5 parts, for example 0.3 parts.

[0024] In a preferred embodiment of the present invention, the amount of the organosilicon polyether copolymer is 1-5 parts, for example 3.5 parts.

[0025] In a preferred embodiment of the present invention, the initiator is dibenzoyl peroxide.

[0026] In a preferred embodiment of the present invention, the amount of the initiator is 0.1-3 parts, for example, 1 part.

[0027] In the present invention, the raw materials may further include a solvent.

[0028] In a preferred embodiment of the present invention, the amount of the solvent is 100 parts.

[0029] In a preferred embodiment of the present invention, the solvent is ethyl acetate.

[0030] The present invention also provides a method for preparing the pressure-sensitive adhesive, comprising the following steps:

[0031] S1, the raw materials of the pressure-sensitive adhesive in the reaction container 1 are used to obtain a mixture A;

[0032] S2, slowly drop 20-40% of the weight of the mixture A into the reaction vessel 2 for 0.5-4 hours, and then keep the mixture at 70-80°C for 0.2-0.4 hours to obtain a mixture B;

[0033] S3, adding the remaining mixed material A into the mixed material B, heating to 70-80° C., reacting for 1-5 hours, to obtain the pressure-sensitive adhesive solution.

[0034] The present invention also provides a pressure-sensitive adhesive tape, which comprises a polyester base film and a pressure-sensitive adhesive, wherein the pressure-sensitive adhesive is formed by curing the pressure-sensitive adhesive liquid.

[0035] The present invention also provides a method for preparing the pressure-sensitive adhesive tape, comprising the following steps:

[0036] The pressure-sensitive adhesive solution is coated on a polyester (PET) release film and dried, and then transferred to a TPU base material or directly coated on a PET base film and placed in an oven for aging to obtain the pressure-sensitive adhesive tape.

[0037] The reagents and raw materials used in the present invention are commercially available.

[0038] The positive and progressive effects of the present invention are:

[0039] The pressure-sensitive adhesive of the present invention has the characteristics of strong viscosity, good waterproofness, easy processing and the like, and can be widely used in the manufacture of various adhesive tapes, labels and the like. DETAILED DESCRIPTION

[0040] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] In the following examples and comparative examples, the full names and English abbreviations of the raw materials are as follows:

[0042] Isooctyl acrylate, 2-EHA, glass transition temperature Tg is -70℃

[0043] Butyl acrylate, BA, glass transition temperature Tg is -55℃

[0044] Glycidyl methacrylate, GMA, glass transition temperature Tg is 40℃

[0045] Acrylic acid, AA, glass transition temperature Tg is 106℃

[0046] 2-Hydroxyethyl methacrylate, HEMA, has a glass transition temperature of 56°C

[0047] Ethyl acetate, EA

[0048] Dodecyl mercaptan, DDM

[0049] Benzoyl peroxide, BPO

[0050] (4-phenylthio)phenyl diphenyl sulfide, photoinitiator 6976, its chemical formula is usually abbreviated as Ar3S + SbF6 - .

[0051] γ-Aminopropyltriethoxysilane, KH550

[0052] Silicone polyether copolymer, DOW OFX-3667

[0053] Silicone polyether copolymer, DOW BY16-201

[0054] Silicone polyether copolymer, DOW OFX-5043

[0055] Silicone polyether copolymer, DOW OFX-0400

[0056] Silicone polyether copolymer, DOW OFX-5211

[0057] Silicone polyether copolymer, DOW OFX-5212

[0058] Silicone polyether copolymer, DOW OFX-0190

[0059] Examples 1-4, Comparative Examples 1-3

[0060] The pressure-sensitive adhesive solutions in Examples 1-4 and Comparative Examples 1-3 are formulated and processed in accordance with parts by weight, as shown in Table 1 below.

[0061] Table 1

[0062]

[0063] According to the formula shown in Table 1, the preparation method of the glue solution is as follows:

[0064] S1: Install a stirrer and a reflux condenser on a 250 mL three-necked flask, open a water bath, increase the temperature, and introduce nitrogen.

[0065] S2: The monomers, initiators and solvents shown in Table 1 are mixed to obtain a blend. When the temperature reaches the set temperature shown in Table 1, 1 / 3 of the blend is added to a three-necked flask as a primer. The mixture is stirred at an appropriate rate (about 300 r / min) and reacted for 1 hour. A constant pressure dropping funnel is then placed to start dropping the remaining 2 / 3 of the blend. The dropping is completed in about 2 hours. After the dropping is completed, the mixture is kept warm for 4 hours. The solvent in the adhesive solution is then removed by reduced pressure distillation to obtain a pressure-sensitive adhesive solution.

[0066] Comparative Example 1

[0067] Except that the silicone polyether copolymer is OFX-5211, other conditions are the same as those in Example 1.

[0068] Comparative Example 2

[0069] Except that the silicone polyether copolymer is OFX-5212, other conditions are the same as those in Example 1.

[0070] Comparative Example 3

[0071] Except that the silicone polyether copolymer is OFX-0190, other conditions are the same as those in Example 1.

[0072] Effect Example 1

[0073] Preparation of pressure-sensitive adhesive tape

[0074] (1) Add 2% of photoinitiator 6976 to the synthesized adhesive solution, mix well and then discharge the material. Take an appropriate amount of adhesive solution with a glass rod and evenly coat it on the polyester film with a coating device SZQ four-sided preparation device. The thickness of the adhesive layer is controlled at 80 μm.

[0075] Place it at 20cm under a high-pressure mercury lamp with a rated power of 250W and a main wavelength of 365nm. After irradiation with ultraviolet light for 40s, the PSA single-sided adhesive is cured to measure the waterproofness of the pressure-sensitive adhesive (excluding polyester film). The specific test method is as follows:

[0076] The water vapor transmission rate (WVTR) evaluation method of pressure-sensitive adhesives refers to ASTM E-96 (Standard test method for water vapor transmission of materials, Procedure BW, inverted water method). The sample must be balanced under the test conditions for 10 hours before testing, and each sample is tested five times to obtain the average value. The reporting unit of WVTR is: g / m 2 / 24 hours.

[0077] (2) Pour out the synthesized glue, add 2% aminosilane coupling agent, mix quickly, take an appropriate amount of glue with a glass rod, and evenly apply it on the polyester film with a coating device. The coating amount is 20g / m 2 , the coating thickness is 80 microns. After being placed in an oven at 80°C for thermal reaction, it is placed in air at 25°C with a relative humidity of 50% for a period of time to obtain a PSA single-sided adhesive. The following properties are measured.

[0078] Peel strength: The test method of 180-degree peel strength is tested according to the national standard (GB 2792-81). Cut the tape into strips with a width of 1 inch (2.54 cm) and a length greater than 200 mm, gently attach them to a standard stainless steel test plate (in accordance with GB / T 3280-1992), and roll the sample with a 2.04 kg hard rubber roller at a speed of about 300 mm / min. Note that when rolling, only the force generated by the mass of the roller can be applied to the sample, and the sample should be rolled back and forth three times. Place it in a constant temperature and humidity controlled environment of 23℃±2℃ and 50%RH±5%RH for 72 hours, and use a standard tensile machine (in accordance with the requirements of JB 706-77 for identification of test machines) to test the peel force at a speed of 12 inches / minute (303mm / min). Each sample is tested three times and the average value is taken in N / mm.

[0079] Adhesion test: Cut the tape into strips 1 inch (2.54cm) wide and about 100mm long. Paste the strip parallel to the longitudinal direction of the plate in the middle of the adjacent standard stainless steel test plate (in accordance with GB / T 3280-1992), ensuring that the bonding area is 1 square inch. Use a 2.04kg hard rubber roller to roll on the sample at a speed of about 300mm / min. Note that when rolling, only the force generated by the mass of the roller can be applied to the sample, and the sample should be rolled back and forth three times. Place it in a constant temperature and humidity controlled environment of 23℃±2℃ and 50%RH±5%RH for 72 hours, then fix the test plate vertically on the test frame, and gently connect the loading plate and 1kg weight with a pin. The entire test frame is placed in a test box adjusted to 100℃. Record the time when the sample falls off the test plate. Each sample is tested three times and the average value is taken in hours. (Note: It is expressed as the time of detachment from the test plate).

[0080] Table 2

[0081]

Claims

1. A pressure-sensitive adhesive, characterized in that: Its raw materials include: 40-60 parts of isooctyl acrylate; 25-50 parts of butyl acrylate; 10-20 parts of glycidyl methacrylate; 1-10 parts of acrylic acid; 1-10 parts of 2-hydroxyethyl methacrylate; 0.1-1.0 parts of dodecyl mercaptan; 1-10 parts of an organosilicon polyether copolymer, wherein the organosilicon polyether copolymer is selected from OFX-3667, BY16-201, OFX-5043, and OFX-0400; 0.1-5.0 parts of initiator.

2. The pressure-sensitive adhesive according to claim 1, characterized in that The number of parts of the isooctyl acrylate is 50 parts; And / or, the amount of butyl acrylate is 25-50 parts, such as 25 parts or 50 parts.

3. The pressure-sensitive adhesive according to claim 1, characterized in that The mass ratio of the isooctyl acrylate to the butyl acrylate is (1-2):

1.

4. The pressure-sensitive adhesive according to claim 1, characterized in that The amount of glycidyl methacrylate is 10-15 parts, such as 12.5 parts or 15 parts.

5. The pressure-sensitive adhesive according to claim 1, characterized in that: The acrylic acid is present in an amount of 1 to 5 parts, such as 3.5 parts or 5 parts; And / or, the amount of 2-hydroxyethyl methacrylate is 1-5 parts, for example 3.5 parts.

6. The pressure-sensitive adhesive according to claim 1, characterized in that: The amount of dodecyl mercaptan is 0.1-0.5 parts, for example 0.3 parts; And / or, the amount of the silicone polyether copolymer is 1-5 parts, for example 3.5 parts.

7. The pressure-sensitive adhesive according to claim 1, characterized in that: The initiator is dibenzoyl peroxide; And / or, the amount of the initiator is 0.1-3 parts, for example 1 part.

8. The pressure-sensitive adhesive according to claim 1, characterized in that: The raw materials also include a solvent, wherein: The number of parts of the solvent is 100; And / or, the solvent is ethyl acetate.

9. A method for preparing a pressure-sensitive adhesive as claimed in any one of claims 1 to 8, characterized in that: The steps include: S1, the raw materials of the pressure-sensitive adhesive in the reaction container 1 are used to obtain a mixture A; S2, slowly drop 20-40% of the weight of the mixture A into the reaction vessel 2 for 0.5-4 hours, and then keep the mixture at 70-80°C for 0.2-0.4 hours to obtain a mixture B; S3, adding the remaining mixed material A into the mixed material B, heating to 70-80° C., reacting for 1-5 hours, to obtain the pressure-sensitive adhesive solution.

10. A pressure-sensitive adhesive tape, characterized in that: The invention comprises a polyester base film and a pressure-sensitive adhesive, wherein the pressure-sensitive adhesive is formed by curing the pressure-sensitive adhesive solution as claimed in any one of claims 1 to 8.

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