Acrylic foam base material and adhesive material

Abstract

The invention discloses an acrylic foam base material and an adhesive material, the base material comprises the following raw materials by weight: 70-100 parts of an acrylic monomer; 100 parts of a first monomer; 0.1 to 1.5 parts of a photoinitiator; 2-9 parts of hollow glass microspheres; 0.05 to 0.2 part of a cross-linking agent; 1-3 parts of fumed silica; 0.005 to 0.2 part of a chain transfer agent; 0.05 to 0.2 part of a silane coupling agent; 0.03 to 0.5 part of nanometer color paste; and 1-3 parts of linear rubber. By optimizing the product composition and utilizing a rubber component adding method, the acrylic foam has the elasticity and tensile strength of rubber, and meanwhile, the acrylic foam can still keep relatively high impact resistance and rebound resilience under a low-temperature condition.

Description

Technical Field

[0001] The invention belongs to the technical field of adhesive tapes, and in particular relates to an acrylic foam substrate and an adhesive material. Background Art

[0002] Acrylic foam pressure-sensitive adhesive is a single-layer pressure-sensitive adhesive whose main component is acrylic resin. This material has the characteristics of high viscosity, strong adhesion, and good weather resistance. Acrylic resin can obtain some special properties by adding some fillers and additives. It is widely used in packaging, electronic appliances, 3C, automotive back panel bonding and other fields. With the diversity of the application range of acrylic foam tape and the improvement of application standards, the requirements for acrylic foam tape are also getting higher and higher.

[0003] Therefore, in view of the above technical problems, it is necessary to provide an acrylic foam substrate and an adhesive material.

[0004] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention

[0005] The purpose of the present invention is to provide an acrylic foam substrate and an adhesive material.

[0006] In order to achieve the above object, a technical solution provided by a specific embodiment of the present invention is as follows:

[0007] The acrylic foam substrate comprises the following raw materials in parts by weight: 70-100 parts of acrylic monomer; 100 parts of first monomer; 0.1-1.5 parts of photoinitiator; 2-9 parts of hollow glass microspheres; 0.05-0.2 parts of crosslinking agent; 1-3 parts of fumed silica; 0.005-0.2 parts of chain transfer agent; 0.05-0.2 parts of silane coupling agent; 0.03-0.5 parts of nano color paste; and 1-3 parts of linear rubber.

[0008] In one or more embodiments of the present invention, the acrylic monomer is selected from n-butyl acrylate, methyl methacrylate, isooctyl acrylate, acrylic acid, hydroxyethyl acrylate, β-carboxyethyl acrylate, isobornyl acrylate, and isobornyl methacrylate.

[0009] In one or more embodiments of the present invention, the first monomer is selected from: N-vinyl pyrrolidone, N-vinyl caprolactam, NN dimethyl amide.

[0010] In one or more embodiments of the present invention, the photoinitiator is selected from: 2-hydroxy-2-methyl-1-phenyl-1-propanone (1173), 1-hydroxycyclohexylphenyl ketone (184), 2-methyl-1-(4-methylthiophenyl)-2-morpholine-1-propanone (907), 4,6-trimethylbenzoyl)phosphine oxide (TPO), α-dimethoxy-α-phenylacetophenone (651), phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (819).

[0011] In one or more embodiments of the present invention, the crosslinking agent is selected from: hexanediol diacrylate HDDA, trimethylolpropane triacrylate TMPTA, and acrylamide AM.

[0012] In one or more embodiments of the present invention, the linear rubber raw material is selected from: SIS rubber, ethylene acrylate rubber AEM, liquid rubber LBR-307.

[0013] In one or more embodiments of the present invention, the hollow glass microspheres are Porter 7014.

[0014] In one or more embodiments of the present invention, the fumed silica is Evonik 972.

[0015] In one or more embodiments of the present invention, 0.05-0.3 parts of a leveling agent is also included.

[0016] In one or more embodiments of the present invention, the leveling agent is selected from BYK-378, BYK-346, and BYK-425.

[0017] In one or more embodiments of the present invention, the silane coupling agent is KBM-403.

[0018] In one or more embodiments of the present invention, the nano-color paste is K-ITUV.

[0019] In one or more embodiments of the present invention, the chain transfer agent is dodecyl mercaptan (NDM).

[0020] In one or more embodiments of the present invention, the adhesive material includes a substrate and an adhesive formed on the substrate, and the substrate is selected from an acrylic foam substrate, and can be an adhesive tape or the like.

[0021] Compared with the prior art, the acrylic foam substrate and adhesive material of the present invention optimize the product composition and utilize the rubber component adding method to enable the acrylic foam to have the elasticity and tensile strength of rubber, and at the same time, can still maintain strong impact resistance and resilience under low temperature conditions. In addition, during the processing, the linear rubber product is dissolved by combining with the preferred acrylic monomer, and a polymer with rubber elasticity is obtained by graft copolymerization in the light curing polymerization process, and the product provides better applicability under low temperature conditions. BRIEF DESCRIPTION OF THE DRAWINGS DETAILED DESCRIPTION

[0022] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0023] Including but not limited to the following embodiments, the application process can be as follows:

[0024] (1) Preparation of prepolymer Propylene monomers are mixed to form a mixed monomer solution, which is added to a reactor. A proper amount of photoinitiator and chain transfer agent are added to the reactor, and the mixture is stirred for 20 minutes under nitrogen protection. After sufficient stirring, the mixture is irradiated with an ultraviolet lamp (a high-pressure mercury lamp or an LED light source with a wavelength of 365 nm) to initiate a polymerization reaction. When the viscosity of the reaction system reaches a certain value, the ultraviolet lamp is turned off to obtain a prepolymer.

[0025] (2) Photocuring to prepare acrylic foam substrate

[0026] 1. Preparation of rubber dispersion by dissolving a linear rubber with a short chain segment, dissolving the first monomer to form a rubber mixture. Take an appropriate amount of the prepolymer in step (1) and mix and stir the rubber mixture, add an initiator, protect with nitrogen, turn on the light, and when the viscosity reaches a suitable level, turn off the light and let in air to terminate the reaction.

[0027] 2. Take appropriate amount of photoinitiator, chain transfer agent, crosslinking agent, hollow glass microspheres, fumed silica, silane coupling agent, leveling agent, nano-color paste, etc., and stir well for 2 hours to mix with the prepolymer solution obtained in step (1) to obtain a slurry. Apply it through a double-roll coating head and obtain an acrylic foam substrate after UV curing.

[0028] (3) Acrylic foam substrate double-sided tape bonding

[0029] Select suitable commercially available heat-curing acrylic system glue, apply 30-50um thickness, and obtain acrylic surface adhesive after light curing. The surface of the substrate is corona treated or primed, and the surface adhesive is bonded to both sides of the substrate by a bonding machine to obtain the finished acrylic foam tape.

[0030] Embodiment 1:

[0031] (1) Preparation of prepolymer:

[0032] A total of 1000 g of isooctyl acrylate, acrylic acid, n-butyl acrylate, isobornyl acrylate and methyl methacrylate were mixed in a ratio of 7:1:1:0.5:0.5 to form a mixed monomer solution, which was added into a reaction kettle. 0.5 g of 1-hydroxycyclohexyl phenyl ketone (184) and 0.05 g of dodecyl mercaptan (NDM) were added into the reaction kettle. The mixture was stirred for 20 minutes under nitrogen protection. After sufficient stirring, a polymerization reaction was initiated under irradiation of an ultraviolet lamp (a high-pressure mercury lamp or an LED light source with a wavelength of 365 nm). When the CPS of the reaction system reached 2000-2500, the ultraviolet lamp was turned off to obtain a prepolymer.

[0033] (2) Preparation of rubber dispersion by dissolution:

[0034] Take 50g N-vinyl pyrrolidone NVP and 1.5g SIS rubber, fully dissolve and stir evenly. Take 200g prepolymer and 30g rubber mixture, stir for 10min with nitrogen, initiate polymerization under ultraviolet lamp (high pressure mercury lamp or LED light source with wavelength of 365nm), turn off the ultraviolet lamp when the CPS of the reaction system reaches 4000-5000, turn on air to stop polymerization and obtain prepolymer containing rubber component.

[0035] (3) Photocuring to prepare acrylic foam substrate

[0036] Take 200g of the prepolymer from step (2), 0.2g of the photoinitiator 4,6-trimethylbenzoyl)phosphine oxide (TPO), 0.1g of a-dimethoxy-a-phenylacetophenone (651), 0.1g of phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (819), 10g of hollow glass microspheres (Porter 7014), 4g of fumed silica (Evonik 972), 0.08g of wetting and leveling agent (BYK-378), 0.2g of silane coupling agent (KBM-403), 0.2g of crosslinking agent (hexanediol diacrylate HDDA), and 0.1g of nano-color paste (Kodi K-ITUV), mix well, and stir for 3h. Then degas under negative pressure for 10min, use a double-roll mixer to apply 0.5mm thickness, and UV light cure for 3.5min (light energy test 600mj / cm 2 / min) to obtain an acrylic foam substrate product.

[0037] The differences between Examples 2-5 and Comparative Example 1 and Example 1 are shown in the following table:

[0038]

[0039]

[0040] Example 6

[0041] The difference between this embodiment and embodiment 1 is only that: 70 parts of acrylic acid monomer n-butyl acrylate; 100 parts of first monomer N-vinyl pyrrolidone; 0.1 parts of photoinitiator 2-hydroxy-2-methyl-1-phenyl-1-propanone (1173); 2 parts of Porter 7014 hollow glass microspheres; 0.05 parts of cross-linking agent hexanediol diacrylate HDDA; 1 part of Evonik 972 fumed silica; 0.005 parts of chain transfer agent dodecyl mercaptan (NDM); 0.05 parts of KBM-403 silane coupling agent; 0.03 parts of Cody K-ITUV nano color paste; 1 part of SIS rubber linear rubber; 0.05 parts of BYK-378 leveling agent.

[0042] Example 7

[0043] The difference between this embodiment and embodiment 1 is only that: 80 parts of acrylic acid monomer n-butyl acrylate; 100 parts of first monomer N-vinyl pyrrolidone; 1 part of photoinitiator 2-hydroxy-2-methyl-1-phenyl-1-propanone (1173); 6 parts of Porter 7014 hollow glass microspheres; 0.1 parts of cross-linking agent hexanediol diacrylate HDDA; 2 parts of Evonik 972 fumed silica; 0.1 parts of chain transfer agent dodecyl mercaptan (NDM); 0.1 parts of KBM-403 silane coupling agent; 0.35 parts of Cody K-ITUV nano color paste; 2 parts of SIS rubber linear rubber; 0.15 parts of BYK-378 leveling agent.

[0044] Example 8

[0045] The difference between this embodiment and embodiment 1 is that: 100 parts of acrylic acid monomer n-butyl acrylate; 100 parts of first monomer N-vinyl pyrrolidone; 1.5 parts of photoinitiator 2-hydroxy-2-methyl-1-phenyl-1-propanone (1173); 9 parts of Porter 7014 hollow glass microspheres; 0.2 parts of crosslinking agent hexanediol diacrylate HDDA; 2 parts of Evonik 972 fumed silica; 0.2 parts of chain transfer agent dodecyl mercaptan (NDM); 0.2 parts of KBM-403 silane coupling agent; 0.5 parts of Cody K-ITUV nano color paste; 3 parts of SIS rubber; 0.3 parts of BYK-378 leveling agent.

[0046] The only difference between Examples 9-11 and Examples 6-8 is that the leveling agent is removed.

[0047] The acrylic foam substrate performance test was performed on the comparative example and the embodiment respectively.

[0048] The test items are as follows:

[0049] 1. Test the hardness with shore C hardness tester, thickness 2.0mm, 500g pressure for 1min, and read the value

[0050] 2. Elongation and tensile strength test method: Cut a 10mm wide and 75mm long sample, the test area is 10mm*25mm, stretch it at a speed of 50mm / min, and read the maximum elongation and tensile strength. The -20℃ tensile strength test is similar, and the tensile strength is tested in a high and low temperature test box.

[0051] 3. Compression / recovery test: Stack 2.0mm thick and cut into 30mm diameter round test blocks. Use 25kg constant pressure for 30 minutes and release for 30 minutes. Record the initial thickness, thickness after compression and thickness after 30 minutes of release respectively, and calculate the compression recovery percentage.

[0052]

[0053]

[0054] The results show that compared with the comparative example, the tensile strength of Examples 1-5 at room temperature is significantly improved. Under low temperature conditions, the elongation of the product of the comparative example without adding rubber mixture decreases by 27%, while the elongation of the substrate with rubber mixture added in the examples decreases by 10-12%, showing obvious low temperature resistance. At the same time, the compression rebound recovery rate also has a relatively obvious recovery ratio.

[0055] In Examples 1-3, the best effect was achieved when the rubber ratio was 2%. In Examples 4-5, the effect of AEM rubber was better than that of SIS rubber, which shows that the addition of rubber components has a significant improvement in the low-temperature application of acrylic foam.

[0056] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

[0057] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. An acrylic foam substrate, comprising the following raw materials in parts by weight: Acrylic acid monomer 70-100 parts; 100 parts of the first monomer; Photoinitiator 0.1-1.5 parts; 2-9 parts of hollow glass microspheres; Cross-linking agent 0.05-0.2 parts; 1-3 parts of fumed silica; Chain transfer agent 0.005-0.2 parts; Silane coupling agent 0.05-0.2 parts; Nano color paste 0.03-0.5 parts; 1-3 parts of linear rubber.

2. The acrylic foam substrate according to claim 1, characterized in that The acrylic acid monomer is selected from the group consisting of n-butyl acrylate, methyl methacrylate, isooctyl acrylate, acrylic acid, hydroxyethyl acrylate, β-carboxyethyl acrylate, isobornyl acrylate, and isobornyl methacrylate.

3. The acrylic foam substrate according to claim 1, characterized in that The photoinitiator is selected from: 2-hydroxy-2-methyl-1-phenyl-1-propanone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1-(4-methylthiophenyl)-2-morpholine-1-propanone, 4,6-trimethylbenzoyl)phosphine oxide, a-dimethoxy-a-phenylacetophenone, and phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide.

4. The acrylic foam substrate according to claim 1, characterized in that The crosslinking agent is selected from: hexanediol diacrylate HDDA, trimethylolpropane triacrylate TMPTA, and acrylamide AM.

5. The acrylic foam substrate according to claim 1, characterized in that: The linear rubber raw material is selected from: SIS rubber, ethylene acrylate rubber AEM, and liquid rubber LBR-307.

6. The acrylic foam substrate according to claim 1, characterized in that: The hollow glass microspheres are Porter 7014.

7. The acrylic foam substrate according to claim 1, characterized in that: The fumed silica is Evonik 972.

8. The acrylic foam substrate according to any one of claims 1 to 7, characterized in that: It also includes 0.05-0.3 parts of leveling agent.

9. The acrylic foam substrate according to claim 8, characterized in that: The leveling agent is selected from BYK-378, BYK-346 and BYK-425.

10. An adhesive material, comprising a substrate and an adhesive formed on the substrate, wherein the substrate is selected from the acrylic foam substrate according to any one of claims 1 to 9.

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