Wiping type acrylate pressure-sensitive adhesive and preparation method thereof

Abstract

The invention discloses an erasable acrylate pressure-sensitive adhesive and a preparation method thereof. The wiping type acrylate pressure-sensitive adhesive is prepared from the following raw materials in parts by weight: 40 to 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; 5 to 10 parts of 2-acrylamido-2-methylpropanesulfonic acid (2-acrylamido-2-methylpropanesulfonic acid); 5 to 10 parts of polyethylene glycol, wherein the weight-average molecular weight of the polyethylene glycol is 1000 to 4000; 0.5 to 1.0 part of a chain transfer agent; 0.5 to 1.0 part of a cross-linking agent; 0.1 to 5.0 parts of an initiator; and a solvent. The erasable acrylate pressure-sensitive adhesive disclosed by the invention has certain hydrophilicity, and residual adhesive appearing in the use process can be wiped by water; meanwhile, certain water resistance is maintained, and good initial adhesion and room-temperature holding power are achieved.

Description

Technical Field

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

[0002] Pressure-sensitive adhesives are extremely sensitive to pressure. At room temperature, they effectively bond to substrates simply by applying pressure. Even after removing the adhesive, the original substrate retains its surface condition.

[0003] There are many types of pressure-sensitive adhesives, mainly natural rubber pressure-sensitive adhesive, synthetic rubber and recycled rubber pressure-sensitive adhesive, silicone and resin pressure-sensitive adhesive, thermoplastic elastomer pressure-sensitive adhesive and acrylate pressure-sensitive adhesive, etc. Acrylate pressure-sensitive adhesive has the advantages of excellent pressure sensitivity, adhesion, antioxidant, light resistance and aging resistance.

[0004] In order to avoid the inability to remove residual adhesive during the use of acrylic pressure-sensitive adhesive, it is of great significance to optimize acrylic pressure-sensitive adhesive.

[0005] Therefore, how to provide a pressure-sensitive adhesive that can ensure initial adhesion and sustained adhesion while also having wipeability and a certain degree of water resistance. Summary of the Invention

[0006] To achieve the above object, the present invention provides a wipeable acrylic pressure-sensitive adhesive and a preparation method thereof.

[0007] The present invention provides a wipeable acrylic pressure-sensitive adhesive, the raw materials of which include, in parts by weight:

[0008] 40-60 parts of isooctyl acrylate;

[0009] 25-50 parts of butyl acrylate;

[0010] 10-20 parts of glycidyl methacrylate;

[0011] 1-10 parts of acrylic acid;

[0012] 1-10 parts of 2-hydroxyethyl methacrylate;

[0013] 5-10 parts of 2-acrylamido-2-methylpropanesulfonic acid;

[0014] 5-10 parts of polyethylene glycol, wherein the weight average molecular weight of the polyethylene glycol is 1000-4000;

[0015] 0.5-1.0 parts of chain transfer agent;

[0016] 0.5-1.0 parts of a cross-linking agent;

[0017] 0.1-5.0 parts of initiator;

[0018] Solvent.

[0019] In a preferred embodiment of the application, the fraction of isooctyl acrylate is 50 parts.

[0020] In a preferred embodiment of the application, the fraction of butyl acrylate is 25-50 parts, such as 25 parts or 50 parts.

[0021] In a preferred embodiment of the application, the mass ratio of isooctyl acrylate and butyl acrylate is (1-3): 1, such as 2: 1 or 2.5: 1.

[0022] In a preferred embodiment of the application, the fraction of glycidyl methacrylate is 10-15 parts, such as 12.5 parts or 15 parts.

[0023] In a preferred embodiment of the application, the fraction of acrylic acid is 1-5 parts, such as 3.5 parts or 5 parts.

[0024] In a preferred embodiment of the application, the fraction of 2-hydroxyethyl methacrylate is 1-5 parts, such as 3.5 parts.

[0025] In a preferred embodiment of the application, the fraction of 2-acrylamido-2-methylpropane sulfonic acid is 6-10 parts, such as 6 parts, 8 parts, 9 parts or 10 parts.

[0026] In a preferred embodiment of the application, the fraction of polyethylene glycol is 6-10 parts, such as 5 parts, 6 parts, 8 parts or 10 parts.

[0027] In a preferred embodiment of the application, the weight average molecular weight of the polyethylene glycol is 1000, 2000, 3000 or 4000.

[0028] In a preferred embodiment of the application, the chain transfer agent is carbon tetrachloride.

[0029] In a preferred embodiment of the application, the fraction of the chain transfer agent is 0.7-1.0 parts, such as 0.7 parts, 0.8 parts or 1.0 parts.

[0030] In a preferred embodiment of the application, the crosslinking agent is JN850 crosslinking agent.

[0031] In a preferred embodiment of the application, the fraction of the crosslinking agent is 0.5-0.8 parts, such as 0.5 parts, 0.6 parts or 0.8 parts.

[0032] In a preferred embodiment of the application, the initiator is dibenzoyl peroxide.

[0033] In a preferred embodiment of the present invention, the amount of the initiator is 0.1-3 parts, for example, 1 part.

[0034] In a preferred embodiment of the present invention, the amount of the solvent is 100 parts.

[0035] In a preferred embodiment of the present invention, the solvent is ethanol with a volume concentration of 95%.

[0036] The present invention also provides a method for preparing the wipeable acrylic pressure-sensitive adhesive, which comprises the following steps:

[0037] S1, mixing the raw materials in a reaction vessel 1 to obtain a mixture A;

[0038] S2, slowly adding 20-40% by weight of the mixture A to the reaction vessel 2 for 0.5-4 hours, and then keeping the mixture at 70-85°C for 0.2-0.4 hours to obtain the mixture B;

[0039] S3, adding the remaining mixed material A dropwise into the mixed material B for 0.5-4 hours, heating to 70-85° C., and reacting for 1-5 hours to obtain the erasable acrylic pressure-sensitive adhesive.

[0040] In a preferred embodiment of the present invention, in S2 , 1 / 3 of the weight portion of the mixed material A is slowly added dropwise into the reaction container 2 .

[0041] In a preferred embodiment of the present invention, in S2, the dropping time is 0.5-2 hours, for example, 1 hour.

[0042] In a preferred embodiment of the present invention, in S2, the dropping is performed while stirring at a speed of 300 r / min.

[0043] In a preferred embodiment of the present invention, in S2, the reaction temperature is 80-85°C.

[0044] In a preferred embodiment of the present invention, in S2, the reaction time is 0.5-2 hours, for example, 1 hour.

[0045] In a preferred embodiment of the present invention, in S3, the dropping time is 1-4 hours, for example, 2 hours.

[0046] In a preferred embodiment of the present invention, in S3, the reaction temperature is 80-85°C.

[0047] In a preferred embodiment of the present invention, in S3, the reaction time is 1-5 hours, for example, 4 hours.

[0048] The reagents and raw materials used in the present invention are commercially available.

[0049] The positive progress effect of the present invention is:

[0050] (1) The wipeable acrylic pressure-sensitive adhesive of the present invention has a certain hydrophilicity, and the residual adhesive produced during use can be wiped clean with water; at the same time, it also maintains a certain water resistance.

[0051] (2) The erasable acrylic pressure-sensitive adhesive of the present invention has good initial tack and room temperature sustained tack. DETAILED DESCRIPTION

[0052] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0053] In the following examples and comparative examples, the full names and English abbreviations of the raw materials are as follows:

[0054] Isooctyl acrylate, 2-EHA, has a glass transition temperature Tg of -70°C;

[0055] Butyl acrylate, BA, has a glass transition temperature Tg of -55°C;

[0056] Glycidyl methacrylate, GMA, has a glass transition temperature Tg of 40°C;

[0057] Acrylic acid, AA, has a glass transition temperature Tg of 106°C;

[0058] 2-Hydroxyethyl methacrylate, HEMA, has a glass transition temperature Tg of 56°C;

[0059] Benzoyl peroxide, BPO;

[0060] Carbon tetrachloride: chemical formula is CCl4;

[0061] Cross-linking agent: JN850 cross-linking agent produced by Hefei Anbang Chemical Co., Ltd.

[0062] PEG1000: polyethylene glycol, a bifunctional polyether with a weight-average molecular weight of 1000;

[0063] PEG2000: polyethylene glycol, a bifunctional polyether with a weight-average molecular weight of 2000;

[0064] PEG3000: polyethylene glycol, a bifunctional polyether with a weight-average molecular weight of 3000;

[0065] PEG4000: polyethylene glycol, a bifunctional polyether with a weight-average molecular weight of 4000;

[0066] PPG2000: polypropylene glycol, a difunctional polyether with a weight average molecular weight of 2000;

[0067] PPG3000: polypropylene glycol, a difunctional polyether with a weight average molecular weight of 3000;

[0068] PPG4000: polypropylene glycol, a difunctional polyether with a weight average molecular weight of 4000;

[0069] AMPS: 2-acrylamido-2-methylpropanesulfonic acid;

[0070] Sodium p-styrenesulfonate: CAS number is 2695-37-6;

[0071] N,N-dimethylacrylamide: CAS number is 2680-03-7;

[0072] N-vinylpyrrolidone: CAS number is 88-12-0.

[0073] Ethanol: refers to ethanol with a volume concentration of 95%.

[0074] Examples 1-4

[0075] The acrylate polymers in Examples 1-4 are formulated in parts by weight as shown in Table 1 below.

[0076] Table 1

[0077]

[0078]

[0079] According to the formula shown in Table 1, the preparation method of acrylate polymer is as follows:

[0080] S1: Install a stirrer and reflux condenser on a 250 mL three-necked flask, open a water bath, increase the temperature, and introduce nitrogen.

[0081] S2: The monomers, chain transfer agent, crosslinking agent, initiator and solvent 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, and the addition is completed dropwise in about 1 hour. At the same time, stirring is carried out at an appropriate rate (about 300 r / min) and the reaction is carried out for 1 hour. After that, a constant pressure dropping funnel is placed to start dropping the remaining 2 / 3 of the blend. The addition is completed dropwise in about 2 hours. After the addition is completed, the mixture is kept warm for a reaction of 4 hours to obtain an acrylate polymer.

[0082] Comparative Example 1

[0083] Except that monomer 6 was replaced by N,N-dimethylacrylamide, other conditions were the same as those in Example 2.

[0084] Comparative Example 2

[0085] Except that monomer 6 was replaced by N-vinyl pyrrolidone, other conditions were the same as those in Example 2.

[0086] Comparative Example 3

[0087] Except that monomer 7 was replaced by PPG2000, other conditions were the same as those in Example 2.

[0088] Comparative Example 4

[0089] Except that monomer 7 was replaced by PPG3000, other conditions were the same as those in Example 2.

[0090] Comparative Example 5

[0091] Except that monomer 7 was replaced by PPG4000, other conditions were the same as those in Example 2.

[0092] Effect embodiment

[0093] (1) Wipeability

[0094] The prepared acrylic pressure-sensitive adhesive was wiped with a damp cloth using a pressure of 4.0 N and a wiping time of 30 seconds. If no residual adhesive remained after wiping, the prepared acrylic pressure-sensitive adhesive was wipeable. If residual adhesive remained after wiping, the prepared acrylic pressure-sensitive adhesive was not wipeable.

[0095] (2) Water resistance

[0096] An acrylic pressure-sensitive adhesive with a specification of 6mm×6mm was pasted on a test iron sheet, and then the sheet was placed in 50°C water. The time for the pressure-sensitive adhesive to turn white and fall off was recorded in detail, and this time was used to measure the water resistance of the prepared pressure-sensitive adhesive.

[0097] (3) Initial adhesion

[0098] The initial tack of pressure-sensitive adhesives was measured according to GB / T 4852-2002, with the tilt angle for measuring the initial tack of pressure-sensitive adhesives set to 30°.

[0099] (4) Adhesion

[0100] The tack of pressure-sensitive adhesives was measured according to GB / T 4851-1998. A 30 mm × 60 mm piece of pressure-sensitive adhesive was pasted onto a test plate.

[0101] A 1000 g weight was hung in the loading plate, and the loading plate drop-off time was recorded as the tack data of the test. The integer tack result was recorded by rounding method.

[0102] The test results are shown in Table 2.

[0103] Table 2

[0104]

[0105]

[0106] According to Table 2, it can be seen that:

[0107] (1) Compared with Comparative Examples 1-5, the erasable acrylate pressure-sensitive adhesive in Examples 1-4 has certain hydrophilicity, and the residual glue appearing in the use process can be wiped clean with water; at the same time, it also maintains certain water resistance.

[0108] (2) Compared with Comparative Examples 1-5, the erasable acrylate pressure-sensitive adhesive in Examples 1-4 has good initial tack and room temperature tack, and the initial tack can reach more than 10#, and the room temperature tack can reach more than 32 h.

Claims

1. A wipeable acrylic pressure-sensitive adhesive, characterized in that: The raw materials include, by weight: 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; 5-10 parts of 2-acrylamido-2-methylpropanesulfonic acid; 5-10 parts of polyethylene glycol, wherein the weight average molecular weight of the polyethylene glycol is 1000-4000; 0.5-1.0 parts of chain transfer agent; 0.5-1.0 parts of a cross-linking agent; 0.1-5.0 parts of initiator; solvent.

2. The erasable acrylic pressure-sensitive adhesive according to claim 1, wherein: The number of parts of the isooctyl acrylate is 50 parts; and / or, the amount of butyl acrylate is 25-50 parts, for example 25 parts or 50 parts; Preferably, the mass ratio of the isooctyl acrylate to the butyl acrylate is (1-3):1, such as 2:1 or 2.5:

1.

3. The erasable acrylic pressure-sensitive adhesive according to claim 1, wherein: The glycidyl methacrylate is present in an amount of 10-15 parts, for example 12.5 parts or 15 parts; and / or, 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.

4. The erasable acrylic pressure-sensitive adhesive according to claim 1, wherein: The number of parts of the 2-acrylamido-2-methylpropanesulfonic acid is 6-10 parts, for example 6 parts, 8 parts, 9 parts or 10 parts; and / or, the polyethylene glycol is present in an amount of 6-10 parts, such as 5 parts, 6 parts, 8 parts or 10 parts; And / or, the weight average molecular weight of the polyethylene glycol is 1000, 2000, 3000 or 4000.

5. The erasable acrylic pressure-sensitive adhesive according to claim 1, wherein: The chain transfer agent is carbon tetrachloride; And / or, the amount of the chain transfer agent is 0.7-1.0 parts, such as 0.7 parts, 0.8 parts or 1.0 parts.

6. The erasable acrylic pressure-sensitive adhesive according to claim 1, wherein: The cross-linking agent is JN850 cross-linking agent; And / or, the cross-linking agent is present in an amount of 0.5-0.8 parts, such as 0.5 parts, 0.6 parts or 0.8 parts.

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

8. The erasable acrylic pressure-sensitive adhesive according to claim 1, wherein: The number of parts of the solvent is 100; And / or, the solvent is ethanol with a volume concentration of 95%.

9. A method for preparing the erasable acrylic pressure-sensitive adhesive according to any one of claims 1 to 8, characterized in that: It includes the following steps: S1, mixing the raw materials in a reaction vessel 1 to obtain a mixture A; S2, slowly adding 20-40% by weight of the mixture A to the reaction vessel 2 for 0.5-4 hours, and then keeping the mixture at 70-85°C for 0.2-0.4 hours to obtain the mixture B; S3, adding the remaining mixed material A dropwise into the mixed material B for 0.5-4 hours, heating to 70-85° C., and reacting for 1-5 hours to obtain the erasable acrylic pressure-sensitive adhesive.

10. The method for preparing the erasable acrylic pressure-sensitive adhesive according to claim 9, wherein: In S2, 1 / 3 of the weight portion of the mixed material A is slowly added dropwise to the reaction container 2; And / or, in S2, the dropping time is 0.5-2h, for example 1h; And / or, in said S2, stirring is performed while said dropping; said stirring speed may be 300 r / min; And / or, in S2, the reaction temperature is 80-85°C; And / or, in S2, the reaction time is 0.5-2h, for example 1h; And / or, in S3, the dropping time is 1-4 hours, for example 2 hours; And / or, in S3, the reaction temperature is 80-85°C; And / or, in S3, the reaction time is 1-5 hours, for example, 4 hours.

Images