Polyacrylate pressure-sensitive adhesive and adhesive tape for electronic products

Abstract

The invention relates to the technical field of pressure-sensitive adhesives, and specifically discloses a polyacrylate pressure-sensitive adhesive and an adhesive tape for electronic products. The polyacrylate pressure-sensitive adhesive comprises the following raw materials: butyl acrylate, glycidyl methacrylate, diethylene glycol diacrylate, tetraethylene glycol diacrylate, mercapto-α-cyclodextrin, a monomer containing adamantane, a chain extender, a filler, an initiator, and water. The preparation method comprises the following steps: adding butyl acrylate, glycidyl methacrylate, diethylene glycol diacrylate, tetraethylene glycol diacrylate, mercapto-α-cyclodextrin, and an initiator into water, heating and stirring for reaction, adding the monomer containing adamantane, a chain extender, and a filler, continuing the stirring for reaction, and cooling to room temperature to obtain the obtained pressure-sensitive adhesive. The obtained pressure-sensitive adhesive has the advantages of high temperature resistance, high peel strength, and low residual adhesive, and can be widely used in electronic products.

Description

Technical Field

[0001] The invention relates to the technical field of pressure-sensitive adhesives, and more specifically to a polyacrylate pressure-sensitive adhesive and an adhesive tape for electronic products. Background Art

[0002] Pressure sensitive adhesive is a special type of viscoelastic polymer, also known as pressure sensitive adhesive. The applicator only needs to apply slight pressure on the surface of the adhesive to make it firmly adhere to the surface of the adhered object in a short time. When the external force is removed, the adhesive effect is still maintained for a long time, and no residue is left on the substrate. Because of its permanent stickiness and dry adhesion, it is also called self-adhesive. It is easy to stick, easy to peel, and does not damage when peeled. Therefore, pressure sensitive adhesive is widely used in packaging, electrical tape, biomedical materials, life labels, electronic equipment, road traffic and aerospace industry.

[0003] At present, CN118374262A discloses an organosilicon-modified polyacrylic acid pressure-sensitive adhesive and a preparation method thereof, wherein the organosilicon-modified polyacrylic acid pressure-sensitive adhesive comprises, by mass fraction, 9-90 polyacrylate pressure-sensitive adhesive, 9-90 organosilicon pressure-sensitive adhesive and 1-50 organosilicon-modified acrylate copolymer; the invention adopts organosilicon-modified acrylate copolymer as a compatibilizer for phase stability, improves the performance stability of the blend of organosilicon pressure-sensitive adhesive and polyacrylate pressure-sensitive adhesive, and thereby improves the high temperature resistance of the pressure-sensitive adhesive to a certain extent; however, the winding structure of the polyacrylic acid chain and the irregularity in the copolymerization process still cause the distribution of organosilicon in the system to become uneven, thereby limiting the organosilicon from fully exerting its high temperature resistance; at the same time, too much organosilicon added to the system will cause the pressure-sensitive adhesive to have a weakened tackiness and reduced peel strength, and may even leave residual adhesive after peeling. These problems not only affect the long-term adhesion effect of the pressure-sensitive adhesive, but also increase the process difficulty and cost of subsequent replacement or maintenance.

[0004] Based on the above statements, the present invention provides a polyacrylate pressure-sensitive adhesive and an adhesive tape for electronic products. Summary of the invention

[0005] In order to solve the problem that the existing polyacrylate pressure-sensitive adhesive cannot have high temperature resistance, high peel strength and low residual adhesive, the present invention provides a polyacrylate pressure-sensitive adhesive and an adhesive tape for electronic products.

[0006] In a first aspect, the present invention provides a polyacrylate pressure-sensitive adhesive for electronic products, which adopts the following technical solution:

[0007] A polyacrylate pressure-sensitive adhesive for electronic products comprises the following raw materials in parts by weight: 60-100 parts of butyl acrylate, 10-30 parts of glycidyl methacrylate, 20-30 parts of diethylene glycol diacrylate, 20-30 parts of tetraethylene glycol diacrylate, 10-20 parts of mercapto-alpha-cyclodextrin, 5-10 parts of adamantane-containing monomer, 7-15 parts of a chain extender, 6-12 parts of a filler, 0.5-1.5 parts of an initiator and 100-200 parts of water.

[0008] Preferably, the mercapto-α-cyclodextrin is prepared by the following method:

[0009] S1. Dissolve α-cyclodextrin in a mixture of N,N-dimethylformamide and dimethyl sulfoxide, add sodium hydroxide, stir for 0.5-1h, cool to 0-5°C, add propylene bromide, stir for 20-30h, filter, and concentrate the filtrate under reduced pressure to obtain allyl-α-cyclodextrin;

[0010] S2. Dissolve 2,2-(1,2-ethylenedioxy)bis(ethyl mercaptan) in tetrahydrofuran, then add allyl-α-cyclodextrin and azobisisobutyronitrile, stir and react at 55-65°C for 8-12h, cool to room temperature, concentrate under reduced pressure, filter, wash and dry to obtain mercapto-α-cyclodextrin.

[0011] Preferably, the usage ratio of α-cyclodextrin, propylene bromide, N,N-dimethylformamide, dimethyl sulfoxide and sodium hydroxide in S1 is 10g:4.5-5mL:40-60mL:40-60mL:2.4g.

[0012] Preferably, the usage ratio of 2,2-(1,2-ethylenedioxy)bis(ethyl mercaptan), tetrahydrofuran, allyl-α-cyclodextrin and azobisisobutyronitrile in S2 is 2.7-3 g:100 mL:8-10 g:0.15-0.2 g.

[0013] Preferably, the adamantane-containing monomer is 1-adamantane acrylate and / or 1-adamantane methyl vinyl ether.

[0014] Further, preferably, the adamantane-containing monomer is obtained by mixing 1-adamantane acrylate and 1-adamantane methyl vinyl ether in a mass ratio of 1-3:5.

[0015] Preferably, the chain extender is at least one of abietic acid, eleostearic acid and eugenol.

[0016] Furthermore, preferably, the chain extender is obtained by mixing abietic acid, eleugylene acid and eugenol in a mass ratio of 1:6:4.

[0017] Preferably, the filler is at least one of nano-silicon dioxide, nano-titanium dioxide, nano-calcium carbonate, and carbon nanotubes.

[0018] Preferably, the initiator is at least one of azobisisobutyronitrile, dibenzoyl peroxide, and dilauroyl peroxide.

[0019] In a second aspect, the present invention provides a method for preparing a polyacrylate pressure-sensitive adhesive for electronic products, using the following technical solution:

[0020] A method for preparing a polyacrylate pressure-sensitive adhesive for electronic products comprises the following steps:

[0021] Butyl acrylate, glycidyl methacrylate, diethylene glycol diacrylate, tetraethylene glycol diacrylate, mercapto-α-cyclodextrin and initiator are added into water, heated in a water bath at 70-80°C, stirred for reaction for 6-8h, then adamantane-containing monomer, chain extender and filler are added, stirred for reaction for 4-6h, cooled to room temperature, and vacuum defoamed for 2-3h to obtain polyacrylate pressure-sensitive adhesive for electronic products.

[0022] In a third aspect, the present invention provides a polyacrylic acid pressure-sensitive adhesive tape for electronic products, which adopts the following technical solution:

[0023] A polyacrylic acid pressure-sensitive adhesive tape for electronic products comprises a substrate and an adhesive layer; the adhesive layer is on one side or both sides of the substrate; the adhesive layer is prepared by curing the polyacrylic acid ester pressure-sensitive adhesive for electronic products.

[0024] In summary, the present invention has the following beneficial effects:

[0025] 1. The present invention uses butyl acrylate, glycidyl methacrylate, diethylene glycol diacrylate, tetraethylene glycol diacrylate, mercapto-α-cyclodextrin, adamantane-containing monomers, chain extenders, fillers, initiators, and water as raw materials to prepare a pressure-sensitive adhesive, and strictly controls the content of each component to promote the interaction between the components. The pressure-sensitive adhesive has excellent high temperature resistance, long adhesion time, high peel strength, and no residual adhesive left after peeling. It is durable and has broad application prospects.

[0026] 2. The present invention uses α-cyclodextrin, propylene bromide and 2,2-(1,2-ethylenedioxy)bis(ethyl mercaptan) as main raw materials to prepare mercapto-α-cyclodextrin. The "hydrophilic outside and hydrophobic inside" α-cyclodextrin has a cavity structure, which can selectively include other components, and the smaller cavity structure reduces the steric hindrance between the components, improves the compatibility between the components, and the introduction of mercapto groups enhances the embedding effect. During the curing process, the active groups on the surface of mercapto-α-cyclodextrin can promote the cross-linking between the components in the pressure-sensitive adhesive to form a more stable network structure, which helps to improve the cohesion and strength of the pressure-sensitive adhesive, thereby improving the peel strength of the pressure-sensitive adhesive, and can effectively avoid the residual adhesive phenomenon after peeling. In addition, mercapto-α-cyclodextrin has excellent antioxidant properties, which can protect the polymer chain from the attack of free radicals, thereby delaying the aging process of the pressure-sensitive adhesive and improving the high temperature resistance and long-term stability of the pressure-sensitive adhesive.

[0027] 3. The pressure-sensitive adhesive of the present invention contains monomers containing adamantane, and the adamantane group has a spirocyclic rigid structure, which can improve the rigidity of the pressure-sensitive adhesive and enhance the heat resistance. The present invention further prefers a mixture of 1-adamantane acrylate and 1-adamantane methyl vinyl ether, which synergistically enhance the effect and increase the cross-linking density to form a polymer with a more complex structure, so that the pressure-sensitive adhesive has higher peel strength and high temperature resistance.

[0028] 4. The present invention selects rosin acid, eleugyl acid and eugenol as chain extenders, and after the three are mixed, they interact and assist each other, the crosslinking density of the pressure-sensitive adhesive system is further increased, and a fully crosslinked network structure with a high crosslinking density is formed after curing, thereby enhancing the bonding strength and high temperature resistance of the pressure-sensitive adhesive.

[0029] 5. The preparation method of the polyacrylate pressure-sensitive adhesive for electronic products of the present invention has simple preparation steps, is green and environmentally friendly, and has positive significance for sustainable development; the obtained pressure-sensitive adhesive has the advantages of high temperature resistance, high peel strength, and low residual adhesive; the adhesive tape prepared by using the polyacrylate pressure-sensitive adhesive of the present invention has excellent performance and can be widely used in electronic products. DETAILED DESCRIPTION

[0030] The present invention is further described in detail below with reference to the embodiments.

[0031] Preparation Examples 1-3 provide methods for preparing mercapto-α-cyclodextrin, and Preparation Example 4 provides a method for preparing mercapto-β-cyclodextrin.

[0032] Preparation Example 1:

[0033] Mercapto-α-cyclodextrin is prepared by the following method:

[0034] S1. Dissolve 10 g of α-cyclodextrin in a mixture of 40 mL of N,N-dimethylformamide and 60 mL of dimethyl sulfoxide, add 2.4 g of sodium hydroxide, stir at a speed of 400 r / min for 0.5 h, cool to 0°C, add 4.5 mL of propylene bromide, continue to stir at the same speed for 20 h, filter, and concentrate the filtrate under reduced pressure to obtain allyl-α-cyclodextrin;

[0035] S2. Dissolve 2.7 g of 2,2-(1,2-ethylenedioxy)bis(ethyl mercaptan) in 100 mL of tetrahydrofuran, add 8 g of allyl-α-cyclodextrin and 0.15 g of azobisisobutyronitrile, stir and react at 55°C at a speed of 400 r / min for 8 h, cool to room temperature, concentrate under reduced pressure, filter, wash and dry to obtain thiol-α-cyclodextrin.

[0036] Preparation Example 2:

[0037] Mercapto-α-cyclodextrin is prepared by the following method:

[0038] S1. Dissolve 10 g of α-cyclodextrin in a mixture of 50 mL of N,N-dimethylformamide and 50 mL of dimethyl sulfoxide, add 2.4 g of sodium hydroxide, stir at a speed of 800 r / min for 0.75 h, cool to 3 ° C, add 4.8 mL of propylene bromide, continue to stir at the same speed for 25 h, filter, and concentrate the filtrate under reduced pressure to obtain allyl-α-cyclodextrin;

[0039] S2. Dissolve 2.8 g of 2,2-(1,2-ethylenedioxy)bis(ethyl mercaptan) in 100 mL of tetrahydrofuran, add 9 g of allyl-α-cyclodextrin and 0.18 g of azobisisobutyronitrile, stir and react at 60°C at a speed of 800 r / min for 10 h, cool to room temperature, concentrate under reduced pressure, filter, wash and dry to obtain thiol-α-cyclodextrin.

[0040] Preparation Example 3:

[0041] Mercapto-α-cyclodextrin is prepared by the following method:

[0042] S1. Dissolve 10 g of α-cyclodextrin in a mixture of 60 mL of N,N-dimethylformamide and 40 mL of dimethyl sulfoxide, add 2.4 g of sodium hydroxide, stir at a speed of 1000 r / min for 1 h, cool to 5°C, add 5 mL of propylene bromide, continue to stir at the same speed for 30 h, filter, and concentrate the filtrate under reduced pressure to obtain allyl-α-cyclodextrin;

[0043] S2. Dissolve 3 g of 2,2-(1,2-ethylenedioxy)bis(ethyl mercaptan) in 100 mL of tetrahydrofuran, add 10 g of allyl-α-cyclodextrin and 0.2 g of azobisisobutyronitrile, stir and react at 65 ° C at a speed of 1000 r / min for 12 h, cool to room temperature, concentrate under reduced pressure, filter, wash and dry to obtain thiol-α-cyclodextrin.

[0044] Preparation Example 4:

[0045] Preparation Example 4 is different from Preparation Example 1 only in that an equal mass of β-cyclodextrin is used to replace α-cyclodextrin, as follows:

[0046] Mercapto-β-cyclodextrin is prepared by the following method:

[0047] S1. Dissolve 10 g of β-cyclodextrin in a mixture of 40 mL of N,N-dimethylformamide and 60 mL of dimethyl sulfoxide, add 2.4 g of sodium hydroxide, stir at a speed of 400 r / min for 0.5 h, cool to 0°C, add 4.5 mL of propylene bromide, continue to stir at the same speed for 20 h, filter, and concentrate the filtrate under reduced pressure to obtain allyl-β-cyclodextrin;

[0048] S2. Dissolve 2.7 g of 2,2-(1,2-ethylenedioxy)bis(ethyl mercaptan) in 100 mL of tetrahydrofuran, add 8 g of allyl-β-cyclodextrin and 0.15 g of azobisisobutyronitrile, stir and react at 55°C at a speed of 400 r / min for 8 h, cool to room temperature, concentrate under reduced pressure, filter, wash and dry to obtain thiol-β-cyclodextrin.

[0049] Embodiments 1-10 provide a polyacrylate pressure-sensitive adhesive for electronic products and a preparation method thereof.

[0050] Embodiment 1:

[0051] A polyacrylate pressure-sensitive adhesive for electronic products, comprising the following raw materials: 60 parts of butyl acrylate, 10 g of glycidyl methacrylate, 20 g of diethylene glycol diacrylate, 20 g of tetraethylene glycol diacrylate, 10 g of mercapto-α-cyclodextrin, 5 g of adamantane-containing monomer, 7 g of a chain extender, 6 g of a filler, 0.5 g of an initiator, and 100 g of water;

[0052] Wherein, mercapto-α-cyclodextrin is prepared by Preparation Example 1; the monomer containing adamantane is 1-adamantane acrylate; the chain extender is eugenol; the filler is nano-silicon dioxide; the initiator is azobisisobutyronitrile;

[0053] A method for preparing a polyacrylate pressure-sensitive adhesive for electronic products comprises the following steps:

[0054] Butyl acrylate, glycidyl methacrylate, diethylene glycol diacrylate, tetraethylene glycol diacrylate, mercapto-α-cyclodextrin and initiator are added into water, heated in a water bath at 70°C, stirred and reacted for 6 hours, then adamantane-containing monomer, chain extender and filler are added, stirred and reacted for 4 hours, cooled to room temperature, and vacuum-defoamed for 2 hours to obtain a polyacrylate pressure-sensitive adhesive for electronic products.

[0055] Embodiment 2:

[0056] A polyacrylate pressure-sensitive adhesive for electronic products, comprising the following raw materials: 80 parts of butyl acrylate, 20 g of glycidyl methacrylate, 25 g of diethylene glycol diacrylate, 25 g of tetraethylene glycol diacrylate, 15 g of mercapto-α-cyclodextrin, 7 g of adamantane-containing monomer, 10 g of a chain extender, 9 g of a filler, 1 g of an initiator, and 150 g of water;

[0057] Wherein, mercapto-α-cyclodextrin is prepared by Preparation Example 2; the monomer containing adamantane is 1-adamantane methyl vinyl ether; the chain extender is rosin acid; the filler is nano-titanium dioxide; the initiator is dibenzoyl peroxide;

[0058] A method for preparing a polyacrylate pressure-sensitive adhesive for electronic products comprises the following steps:

[0059] Butyl acrylate, glycidyl methacrylate, diethylene glycol diacrylate, tetraethylene glycol diacrylate, mercapto-α-cyclodextrin and initiator are added to water, heated in a water bath at 75°C, stirred and reacted for 7 hours, then adamantane-containing monomer, chain extender and filler are added, stirred and reacted for 5 hours, cooled to room temperature, and vacuum defoamed for 2-3 hours to obtain a polyacrylate pressure-sensitive adhesive for electronic products.

[0060] Embodiment 3:

[0061] A polyacrylate pressure-sensitive adhesive for electronic products, comprising the following raw materials: 100 parts of butyl acrylate, 30 g of glycidyl methacrylate, 30 g of diethylene glycol diacrylate, 30 g of tetraethylene glycol diacrylate, 20 g of mercapto-α-cyclodextrin, 10 g of adamantane-containing monomer, 15 g of a chain extender, 12 g of a filler, 1.5 g of an initiator, and 200 g of water;

[0062] Wherein, mercapto-α-cyclodextrin is prepared by Preparation Example 3; the monomer containing adamantane is obtained by mixing 1-adamantane acrylate and 1-adamantane methyl vinyl ether in a mass ratio of 1:1; the chain extender is obtained by mixing eleostearic acid and eugenol in a mass ratio of 3:1; the filler is obtained by mixing nano-silicon dioxide, nano-titanium dioxide and nano-calcium carbonate in a mass ratio of 1:1:1; the initiator is azobisisobutyronitrile;

[0063] A method for preparing a polyacrylate pressure-sensitive adhesive for electronic products comprises the following steps:

[0064] Butyl acrylate, glycidyl methacrylate, diethylene glycol diacrylate, tetraethylene glycol diacrylate, mercapto-α-cyclodextrin and initiator are added into water, heated in a water bath at 80°C, stirred and reacted for 8 hours, then adamantane-containing monomer, chain extender and filler are added, stirred and reacted for 6 hours, cooled to room temperature, and vacuum-defoamed for 3 hours to obtain a polyacrylate pressure-sensitive adhesive for electronic products.

[0065] Embodiment 4:

[0066] Example 4 is different from Example 1 only in that the monomer containing adamantane is 1-adamantane methyl vinyl ether, specifically as follows:

[0067] A polyacrylate pressure-sensitive adhesive for electronic products, comprising the following raw materials: 60 parts of butyl acrylate, 10 g of glycidyl methacrylate, 20 g of diethylene glycol diacrylate, 20 g of tetraethylene glycol diacrylate, 10 g of mercapto-α-cyclodextrin, 5 g of adamantane-containing monomer, 7 g of a chain extender, 6 g of a filler, 0.5 g of an initiator, and 100 g of water;

[0068] Wherein, mercapto-α-cyclodextrin is prepared by Preparation Example 1; the monomer containing adamantane is 1-adamantane methyl vinyl ether; the chain extender is eugenol; the filler is nano-silicon dioxide; the initiator is azobisisobutyronitrile;

[0069] A method for preparing a polyacrylate pressure-sensitive adhesive for electronic products comprises the following steps:

[0070] Butyl acrylate, glycidyl methacrylate, diethylene glycol diacrylate, tetraethylene glycol diacrylate, mercapto-α-cyclodextrin and initiator are added into water, heated in a water bath at 70°C, stirred and reacted for 6 hours, then adamantane-containing monomer, chain extender and filler are added, stirred and reacted for 4 hours, cooled to room temperature, and vacuum-defoamed for 2 hours to obtain a polyacrylate pressure-sensitive adhesive for electronic products.

[0071] Embodiment 5:

[0072] Example 5 is different from Example 1 only in that the monomer containing adamantane is obtained by mixing 1-adamantane acrylate and 1-adamantane methyl vinyl ether in a mass ratio of 1:5, as follows:

[0073] A polyacrylate pressure-sensitive adhesive for electronic products, comprising the following raw materials: 60 parts of butyl acrylate, 10 g of glycidyl methacrylate, 20 g of diethylene glycol diacrylate, 20 g of tetraethylene glycol diacrylate, 10 g of mercapto-α-cyclodextrin, 5 g of adamantane-containing monomer, 7 g of a chain extender, 6 g of a filler, 0.5 g of an initiator, and 100 g of water;

[0074] Wherein, mercapto-α-cyclodextrin is prepared in Preparation Example 1; the monomer containing adamantane is obtained by mixing 1-adamantane acrylate and 1-adamantane methyl vinyl ether in a mass ratio of 1:5; the chain extender is eugenol; the filler is nano-silicon dioxide; and the initiator is azobisisobutyronitrile;

[0075] A method for preparing a polyacrylate pressure-sensitive adhesive for electronic products comprises the following steps:

[0076] Butyl acrylate, glycidyl methacrylate, diethylene glycol diacrylate, tetraethylene glycol diacrylate, mercapto-α-cyclodextrin and initiator are added into water, heated in a water bath at 70°C, stirred and reacted for 6 hours, then adamantane-containing monomer, chain extender and filler are added, stirred and reacted for 4 hours, cooled to room temperature, and vacuum-defoamed for 2 hours to obtain a polyacrylate pressure-sensitive adhesive for electronic products.

[0077] Embodiment 6:

[0078] Example 6 is different from Example 1 only in that the adamantane-containing monomer is obtained by mixing 1-adamantane acrylate and 1-adamantane methyl vinyl ether in a mass ratio of 3:5, as follows:

[0079] A polyacrylate pressure-sensitive adhesive for electronic products, comprising the following raw materials: 60 parts of butyl acrylate, 10 g of glycidyl methacrylate, 20 g of diethylene glycol diacrylate, 20 g of tetraethylene glycol diacrylate, 10 g of mercapto-α-cyclodextrin, 5 g of adamantane-containing monomer, 7 g of a chain extender, 6 g of a filler, 0.5 g of an initiator, and 100 g of water;

[0080] Wherein, mercapto-α-cyclodextrin is prepared in Preparation Example 1; the monomer containing adamantane is obtained by mixing 1-adamantane acrylate and 1-adamantane methyl vinyl ether in a mass ratio of 3:5; the chain extender is eugenol; the filler is nano-silicon dioxide; the initiator is azobisisobutyronitrile;

[0081] A method for preparing a polyacrylate pressure-sensitive adhesive for electronic products comprises the following steps:

[0082] Butyl acrylate, glycidyl methacrylate, diethylene glycol diacrylate, tetraethylene glycol diacrylate, mercapto-α-cyclodextrin and initiator are added into water, heated in a water bath at 70°C, stirred and reacted for 6 hours, then adamantane-containing monomer, chain extender and filler are added, stirred and reacted for 4 hours, cooled to room temperature, and vacuum-defoamed for 2 hours to obtain a polyacrylate pressure-sensitive adhesive for electronic products.

[0083] Embodiment 7:

[0084] Example 7 is different from Example 1 only in that the chain extender is obtained by mixing rosin acid and eleostearic acid in a mass ratio of 1:1, as follows:

[0085] A polyacrylate pressure-sensitive adhesive for electronic products, comprising the following raw materials: 60 parts of butyl acrylate, 10 g of glycidyl methacrylate, 20 g of diethylene glycol diacrylate, 20 g of tetraethylene glycol diacrylate, 10 g of mercapto-α-cyclodextrin, 5 g of adamantane-containing monomer, 7 g of a chain extender, 6 g of a filler, 0.5 g of an initiator, and 100 g of water;

[0086] Wherein, mercapto-α-cyclodextrin is prepared by Preparation Example 1; the monomer containing adamantane is 1-adamantane acrylate; the chain extender is obtained by mixing rosin acid and tung oil acid in a mass ratio of 1:1; the filler is nano-silicon dioxide; and the initiator is azobisisobutyronitrile;

[0087] A method for preparing a polyacrylate pressure-sensitive adhesive for electronic products comprises the following steps:

[0088] Butyl acrylate, glycidyl methacrylate, diethylene glycol diacrylate, tetraethylene glycol diacrylate, mercapto-α-cyclodextrin and initiator are added into water, heated in a water bath at 70°C, stirred and reacted for 6 hours, then adamantane-containing monomer, chain extender and filler are added, stirred and reacted for 4 hours, cooled to room temperature, and vacuum-defoamed for 2 hours to obtain a polyacrylate pressure-sensitive adhesive for electronic products.

[0089] Embodiment 8:

[0090] Example 8 is different from Example 1 only in that the chain extender is obtained by mixing rosin acid and eugenol in a mass ratio of 1:1, as follows:

[0091] A polyacrylate pressure-sensitive adhesive for electronic products, comprising the following raw materials: 60 parts of butyl acrylate, 10 g of glycidyl methacrylate, 20 g of diethylene glycol diacrylate, 20 g of tetraethylene glycol diacrylate, 10 g of mercapto-α-cyclodextrin, 5 g of adamantane-containing monomer, 7 g of a chain extender, 6 g of a filler, 0.5 g of an initiator, and 100 g of water;

[0092] Wherein, mercapto-α-cyclodextrin is prepared by Preparation Example 1; the monomer containing adamantane is 1-adamantane acrylate; the chain extender is obtained by mixing rosin acid and eugenol in a mass ratio of 1:1; the filler is nano-silicon dioxide; and the initiator is azobisisobutyronitrile;

[0093] A method for preparing a polyacrylate pressure-sensitive adhesive for electronic products comprises the following steps:

[0094] Butyl acrylate, glycidyl methacrylate, diethylene glycol diacrylate, tetraethylene glycol diacrylate, mercapto-α-cyclodextrin and initiator are added into water, heated in a water bath at 70°C, stirred and reacted for 6 hours, then adamantane-containing monomer, chain extender and filler are added, stirred and reacted for 4 hours, cooled to room temperature, and vacuum-defoamed for 2 hours to obtain a polyacrylate pressure-sensitive adhesive for electronic products.

[0095] Embodiment 9:

[0096] Example 9 is different from Example 1 only in that the chain extender is obtained by mixing eugenol and eleostearic acid in a mass ratio of 1:1, as follows:

[0097] A polyacrylate pressure-sensitive adhesive for electronic products, comprising the following raw materials: 60 parts of butyl acrylate, 10 g of glycidyl methacrylate, 20 g of diethylene glycol diacrylate, 20 g of tetraethylene glycol diacrylate, 10 g of mercapto-α-cyclodextrin, 5 g of adamantane-containing monomer, 7 g of a chain extender, 6 g of a filler, 0.5 g of an initiator, and 100 g of water;

[0098] Wherein, mercapto-α-cyclodextrin is prepared by Preparation Example 1; the monomer containing adamantane is 1-adamantane acrylate; the chain extender is obtained by mixing eugenol and eleostearic acid in a mass ratio of 1:1; the filler is nano-silicon dioxide; and the initiator is azobisisobutyronitrile;

[0099] A method for preparing a polyacrylate pressure-sensitive adhesive for electronic products comprises the following steps:

[0100] Butyl acrylate, glycidyl methacrylate, diethylene glycol diacrylate, tetraethylene glycol diacrylate, mercapto-α-cyclodextrin and initiator are added into water, heated in a water bath at 70°C, stirred and reacted for 6 hours, then adamantane-containing monomer, chain extender and filler are added, stirred and reacted for 4 hours, cooled to room temperature, and vacuum-defoamed for 2 hours to obtain a polyacrylate pressure-sensitive adhesive for electronic products.

[0101] Embodiment 10:

[0102] Example 10 is different from Example 1 only in that the chain extender is obtained by mixing rosin acid, eleostearic acid and eugenol in a mass ratio of 1:6:4, as follows:

[0103] A polyacrylate pressure-sensitive adhesive for electronic products, comprising the following raw materials: 60 parts of butyl acrylate, 10 g of glycidyl methacrylate, 20 g of diethylene glycol diacrylate, 20 g of tetraethylene glycol diacrylate, 10 g of mercapto-α-cyclodextrin, 5 g of adamantane-containing monomer, 7 g of a chain extender, 6 g of a filler, 0.5 g of an initiator, and 100 g of water;

[0104] Wherein, mercapto-α-cyclodextrin is prepared by Preparation Example 1; the monomer containing adamantane is 1-adamantane acrylate; the chain extender is obtained by mixing rosin acid, eleugyl acid and eugenol in a mass ratio of 1:6:4; the filler is nano-silicon dioxide; and the initiator is azobisisobutyronitrile;

[0105] A method for preparing a polyacrylate pressure-sensitive adhesive for electronic products comprises the following steps:

[0106] Butyl acrylate, glycidyl methacrylate, diethylene glycol diacrylate, tetraethylene glycol diacrylate, mercapto-α-cyclodextrin and initiator are added into water, heated in a water bath at 70°C, stirred and reacted for 6 hours, then adamantane-containing monomer, chain extender and filler are added, stirred and reacted for 4 hours, cooled to room temperature, and vacuum-defoamed for 2 hours to obtain a polyacrylate pressure-sensitive adhesive for electronic products.

[0107] In order to verify the comprehensive performance of the polyacrylate pressure-sensitive adhesive for electronic products prepared in Examples 1-10 of the present invention, the applicant set up Comparative Examples 1-4, which are as follows:

[0108] Comparative Example 1:

[0109] Comparative Example 1 is different from Example 1 only in that an equal mass of mercapto-β-cyclodextrin is used to replace mercapto-α-cyclodextrin, as follows:

[0110] A polyacrylate pressure-sensitive adhesive for electronic products, comprising the following raw materials: 60 parts of butyl acrylate, 10 g of glycidyl methacrylate, 20 g of diethylene glycol diacrylate, 20 g of tetraethylene glycol diacrylate, 10 g of mercapto-β-cyclodextrin, 5 g of adamantane-containing monomer, 7 g of a chain extender, 6 g of a filler, 0.5 g of an initiator, and 100 g of water;

[0111] Wherein, mercapto-β-cyclodextrin is prepared by Preparation Example 4; the monomer containing adamantane is 1-adamantane acrylate; the chain extender is eugenol; the filler is nano-silicon dioxide; the initiator is azobisisobutyronitrile;

[0112] A method for preparing a polyacrylate pressure-sensitive adhesive for electronic products comprises the following steps:

[0113] Butyl acrylate, glycidyl methacrylate, diethylene glycol diacrylate, tetraethylene glycol diacrylate, mercapto-β-cyclodextrin and initiator are added to water, heated in a water bath at 70°C, stirred and reacted for 6 hours, then adamantane-containing monomer, chain extender and filler are added, stirred and reacted for 4 hours, cooled to room temperature, and vacuum defoamed for 2 hours to obtain a polyacrylate pressure-sensitive adhesive for electronic products.

[0114] Comparative Example 2:

[0115] Comparative Example 2 is different from Example 1 only in that an equal mass of allyl-β-cyclodextrin is used to replace mercapto-α-cyclodextrin, as follows:

[0116] A polyacrylate pressure-sensitive adhesive for electronic products, comprising the following raw materials: 60 parts of butyl acrylate, 10 g of glycidyl methacrylate, 20 g of diethylene glycol diacrylate, 20 g of tetraethylene glycol diacrylate, 10 g of allyl-β-cyclodextrin, 5 g of adamantane-containing monomer, 7 g of chain extender, 6 g of filler, 0.5 g of initiator, and 100 g of water;

[0117] Wherein, allyl-β-cyclodextrin is prepared by step S1 of Preparation Example 1; the monomer containing adamantane is 1-adamantane acrylate; the chain extender is eugenol; the filler is nano-silicon dioxide; and the initiator is azobisisobutyronitrile;

[0118] A method for preparing a polyacrylate pressure-sensitive adhesive for electronic products comprises the following steps:

[0119] Butyl acrylate, glycidyl methacrylate, diethylene glycol diacrylate, tetraethylene glycol diacrylate, allyl-β-cyclodextrin and initiator are added into water, heated in a water bath at 70°C, stirred and reacted for 6 hours, then adamantane-containing monomer, chain extender and filler are added, stirred and reacted for 4 hours, cooled to room temperature, and vacuum-defoamed for 2 hours to obtain a polyacrylate pressure-sensitive adhesive for electronic products.

[0120] Comparative Example 3:

[0121] Comparative Example 3 is different from Example 1 only in that the monomer containing adamantane is replaced by an equal mass of acrylic acid, as follows:

[0122] A polyacrylate pressure-sensitive adhesive for electronic products, comprising the following raw materials: 60 parts of butyl acrylate, 10 g of glycidyl methacrylate, 20 g of diethylene glycol diacrylate, 20 g of tetraethylene glycol diacrylate, 10 g of mercapto-α-cyclodextrin, 5 g of acrylic acid, 7 g of a chain extender, 6 g of a filler, 0.5 g of an initiator, and 100 g of water;

[0123] Wherein, mercapto-α-cyclodextrin is prepared by Preparation Example 1; the chain extender is eugenol; the filler is nano-silicon dioxide; the initiator is azobisisobutyronitrile;

[0124] A method for preparing a polyacrylate pressure-sensitive adhesive for electronic products comprises the following steps:

[0125] Butyl acrylate, glycidyl methacrylate, diethylene glycol diacrylate, tetraethylene glycol diacrylate, mercapto-α-cyclodextrin and initiator are added to water, heated in a water bath at 70°C, stirred and reacted for 6 hours, acrylic acid, chain extender and filler are added, stirred and reacted for 4 hours, cooled to room temperature, and vacuum defoamed for 2 hours to obtain a polyacrylate pressure-sensitive adhesive for electronic products.

[0126] Comparative Example 4:

[0127] Comparative Example 4 is different from Example 1 only in that the chain extender is replaced by styrene of the same mass, as follows:

[0128] A polyacrylate pressure-sensitive adhesive for electronic products, comprising the following raw materials: 60 parts of butyl acrylate, 10 g of glycidyl methacrylate, 20 g of diethylene glycol diacrylate, 20 g of tetraethylene glycol diacrylate, 10 g of mercapto-α-cyclodextrin, 5 g of adamantane-containing monomer, 7 g of styrene, 6 g of filler, 0.5 g of initiator, and 100 g of water;

[0129] Wherein, mercapto-α-cyclodextrin is prepared by Preparation Example 1; the monomer containing adamantane is 1-adamantane acrylate; the filler is nano-silicon dioxide; the initiator is azobisisobutyronitrile;

[0130] A method for preparing a polyacrylate pressure-sensitive adhesive for electronic products comprises the following steps:

[0131] Butyl acrylate, glycidyl methacrylate, diethylene glycol diacrylate, tetraethylene glycol diacrylate, mercapto-α-cyclodextrin and initiator are added into water, heated in a water bath at 70°C, stirred and reacted for 6 hours, then adamantane-containing monomer, styrene and filler are added, stirred and reacted for 4 hours, cooled to room temperature, and vacuum-defoamed for 2 hours to obtain a polyacrylate pressure-sensitive adhesive for electronic products.

[0132] Performance testing:

[0133] The pressure-sensitive adhesives obtained in Examples 1-10 and Comparative Examples 1-4 of the present invention were uniformly coated on a substrate PE film, dried at 120°C for 15 min, transferred to an oven at 80°C for aging for 24 h, taken out, and rolled and cut after cooling to obtain pressure-sensitive adhesive tapes. The performance tests were performed, and the results are shown in Table 1:

[0134] Refer to GB / T2792-2014 "Test method for peel strength of adhesive tape" to conduct 180° peel strength test on pressure-sensitive tape and pressure-sensitive tape treated in an oven at 100°C for 24 hours to determine the high temperature resistance of the pressure-sensitive tape;

[0135] Refer to GB / T4852-2002 "Pressure-sensitive Adhesive Tape Initial Adhesion Test Method (Rolling Ball Method)" to conduct initial adhesion test and determine the adhesive strength of the pressure-sensitive adhesive tape;

[0136] Refer to GB / T4851-2014 "Test method for adhesive tape holding force" for holding force test;

[0137] With reference to GB / T32368-2015 "Test method for high temperature and high humidity aging resistance of adhesive tapes", the pressure-sensitive tape was placed in a constant temperature and humidity chamber, and the temperature was set to 65°C and the relative humidity was 85%. After aging treatment for 7 days, it was placed in a standard environment with a temperature of 23°C and a relative humidity of 50% for 2 hours. The degree of curling of the pressure-sensitive tape was observed and the changes were recorded. After the pressure-sensitive tape was placed for 2 days, the tape on the surface of the steel plate was gently torn off to observe whether there was any residual glue.

[0138] Table 1

[0139]

[0140] From the data shown in Table 1 above, it can be seen that the comprehensive performance of the polyacrylate pressure-sensitive adhesive for electronic products prepared in Examples 1-10 is significantly better than that of Comparative Examples 1-4, has high bonding strength and high holding force, can meet the requirements of long-term use under high temperature conditions, and has broad market prospects.

[0141] It can be seen from Example 1 and Comparative Examples 1 and 2 that: the present invention uses α-cyclodextrin to be first treated with vinyl bromide to obtain allyl-α-cyclodextrin; allyl-α-cyclodextrin and 2,2-(1,2-ethylenedioxy)bisethylmercaptan are chemically bonded to obtain mercapto-α-cyclodextrin; the pressure-sensitive adhesive of the present invention adds mercapto-α-cyclodextrin, which still maintains excellent bonding strength at high temperature, does not change after aging, and does not leave residual adhesive when torn off.

[0142] It can be seen from Example 1 and Comparative Example 3 that adding adamantane-containing monomers to the pressure-sensitive adhesive of the present invention can effectively improve the high temperature resistance of the pressure-sensitive adhesive. Further comparison shows that from Example 1 and Examples 4-6, the adamantane-containing monomer is a mixture of 1-adamantane acrylate and 1-adamantane methyl vinyl ether, which is more conducive to improving the high temperature resistance of the pressure-sensitive adhesive, and will not curl up or bend after aging.

[0143] It can be seen from Example 1 and Comparative Example 4 that the present invention adds a chain extender to significantly improve the high temperature resistance of the pressure-sensitive adhesive. Further comparison of Example 1 with Examples 7-10 shows that the chain extender is a mixture of rosin acid, tung oil acid, and eugenol. The three act synergistically and show more excellent performance in terms of high temperature resistance, aging resistance, and bonding strength, and there is no residual glue after peeling.

[0144] This specific embodiment is merely an explanation of the present invention and is not a limitation of the present invention. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed. However, as long as they are within the scope of the claims of the present invention, they are protected by the patent law.

Claims

1. A polyacrylate pressure-sensitive adhesive for electronic products, characterized in that: The invention comprises the following raw materials in parts by weight: 60-100 parts of butyl acrylate, 10-30 parts of glycidyl methacrylate, 20-30 parts of diethylene glycol diacrylate, 20-30 parts of tetraethylene glycol diacrylate, 10-20 parts of mercapto-α-cyclodextrin, 5-10 parts of adamantane-containing monomer, 7-15 parts of a chain extender, 6-12 parts of a filler, 0.5-1.5 parts of an initiator, and 100-200 parts of water; The mercapto-α-cyclodextrin is prepared by the following method: S1. Dissolve α-cyclodextrin in a mixture of N,N-dimethylformamide and dimethyl sulfoxide, add sodium hydroxide, stir for 0.5-1h, cool to 0-5°C, add propylene bromide, stir for 20-30h, filter, and concentrate the filtrate under reduced pressure to obtain allyl-α-cyclodextrin; S2, dissolving 2,2-(1,2-ethylenedioxy)bis(ethyl mercaptan) in tetrahydrofuran, then adding allyl-α-cyclodextrin and azobisisobutyronitrile, stirring and reacting at 55-65° C. for 8-12 hours, cooling to room temperature, concentrating under reduced pressure, filtering, washing, and drying to obtain thiol-α-cyclodextrin; The usage ratio of α-cyclodextrin, propylene bromide, N,N-dimethylformamide, dimethyl sulfoxide and sodium hydroxide in S1 is 10g:4.5-5mL:40-60mL:40-60mL:2.4g; The usage ratio of 2,2-(1,2-ethylenedioxy)bis(ethyl mercaptan), tetrahydrofuran, allyl-α-cyclodextrin, and azobisisobutyronitrile in S2 is 2.7-3 g:100 mL:8-10 g:0.15-0.2 g; The adamantane-containing monomer is 1-adamantane acrylate and / or 1-adamantane methyl vinyl ether; The chain extender is at least one of abietic acid, eleugyl acid and eugenol.

2. The polyacrylate pressure-sensitive adhesive for electronic products according to claim 1, characterized in that: The adamantane-containing monomer is obtained by mixing 1-adamantane acrylate and 1-adamantane methyl vinyl ether in a mass ratio of 1-3:

5.

3. The polyacrylate pressure-sensitive adhesive for electronic products according to claim 1, characterized in that: The chain extender is obtained by mixing rosin acid, eleugyl acid and eugenol in a mass ratio of 1:6:

4.

4. The polyacrylate pressure-sensitive adhesive for electronic products according to claim 1, characterized in that: The filler is at least one of nano silicon dioxide, nano titanium dioxide, nano calcium carbonate and carbon nanotubes; the initiator is at least one of azobisisobutyronitrile, dibenzoyl peroxide and dilauroyl peroxide.

5. A method for preparing the polyacrylate pressure-sensitive adhesive for electronic products according to any one of claims 1 to 4, characterized in that: The following steps are involved: Butyl acrylate, glycidyl methacrylate, diethylene glycol diacrylate, tetraethylene glycol diacrylate, mercapto-α-cyclodextrin and initiator are added into water, heated in a water bath at 70-80°C, stirred for reaction for 6-8h, then adamantane-containing monomer, chain extender and filler are added, stirred for reaction for 4-6h, cooled to room temperature, and vacuum defoamed for 2-3h to obtain polyacrylate pressure-sensitive adhesive for electronic products.

6. A polyacrylate pressure-sensitive adhesive tape for electronic products, characterized in that: The invention comprises a substrate and an adhesive layer; the adhesive layer is on one side or both sides of the substrate; the adhesive layer is prepared by curing the polyacrylate pressure-sensitive adhesive for electronic products according to any one of claims 1 to 4.

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